Abstract: A choke valve is controlled finely suited to the running state of an engine. A throttle valve 8 and a choke valve 9 are provided in series on an intake pipe 6, and the opening degree of the choke valve 9 is controlled by a stepping motor. The choke valve opening degree upon start of engine (start opening degree) is determined depending on the engine temperature. The stepping motor 11 is initialized at the fully closed side of the choke valve 9 when the power source for starting the engine is turned on. The start opening degree of the choke valve is judged to be closer to the fully closed side or fully opened side, and the stepping motor 11 is initialized at the fully closed side if judged to be close to the fully closed side, and at the fully opened side if at the fully opened side.

Abstract: In an engine output condition informing system for a snow remover, the engine speed and the throttle position are detected, the output power rate OPrate of the engine is estimated based thereon, the output power condition of the engine is determined based on the estimated output power rate, and the operator is informed of the determined output power condition by the display (informing) device. With this, the output power condition of the engine can be accurately determined and the operator informed with a simple configuration, whereby the burden on the operator can be lightened. Also, it is possible to minimize situations in which the output power condition of the engine is overpowered and the power train of the engine or of the snow removal mechanism and travel mechanism is damaged, as well as situations in which the output power condition of the engine becomes underpowered, the snow remover is unable to perform, and the operating efficiency decreases.

Abstract: In an engine speed control system for a snow remover, the engine speed is controlled at the desired speed by driving the throttle valve with an electric motor, the engine output power corresponding to the load acting on the snow removal mechanism or travel mechanism is estimated based on the throttle position and the engine speed, and the desired speed is increased in stepwise fashion to a higher value when the estimated engine output power exceeds first through third ascending threshold values. With this, the engine speed maintained when a small load is acting on the snow removal mechanism or travel mechanism can be set to a lower value, whereby the noise level can be reduced and fuel efficiency improved compared with the prior art wherein a mechanical governor is used to adjust the engine speed.

Abstract: A control system for general-purpose spark-ignition internal combustion engine to be used for a portable generator, etc., having one or two cylinders and an actuator connected to the throttle valve to open or close the throttle value. In the system, an adaptive controller with a parameter identification mechanism is provided which receives a detected engine speed and a desired engine speed as inputs, and computes a command value to be supplied to the actuator, using an adaptive parameter identified by the parameter identification mechanism, such that the detected engine speed is brought to the desired speed. In the system, the desired engine speed is determined such that the desired engine speed per unit time is not greater than a prescribed value and the command value is determined to be within the upper and lower limits of the throttle value.

Abstract: In a control system of a lawn mower having an internal combustion engine controlled to a desired engine speed by a throttle actuator, a blade connected to the engine to be driven to cut grass, an engine output is estimated based on a detected throttle position and the desired engine speed, and when the estimated engine output exceeds a prescribed value, the grass bag is determined to be full of cut grass. With this, a full grass bag can be detected and the operator informed without providing a dedicated sensor.

Abstract: In a throttle device for a multipurpose internal combustion engine having a throttle valve connected to an electric motor and a carburetor, when an instruction to stop the engine is inputted, the electric motor is controlled to move the throttle valve in a fully closed position so as to stop the engine, and then to move the throttle valve in a fully opened direction. With this, throttle valve can be surely opened to facilitate restarting, and the occurrence of dieseling and run-on is prevented without providing a fuel cut valve to the carburetor. Further, a spring is provided to urge the throttle valve in an opening direction. With this, the response in opening the throttle valve is enhanced and the size of the motor is reduced.

Abstract: In a lawnmower engine speed control system having an actuator moving a throttle valve and a controller controlling operation of the actuator such that the engine speed becomes equal to a predefined desired engine speed, it is determined whether the lawnmower is under a mowing operation based on a value indicative of a load of the engine including an operation rate or output of the engine, the desired engine speed is changed based on a result of determination, thereby enabling to lower noise, to boost fuel efficiency, and to simplify operation by making manual regulation of engine speed unnecessary, while ensuring stable operation free from engine speed variance.

Abstract: In a throttle device for a multipurpose internal combustion engine having a throttle valve, a throttle shaft connected to the throttle valve and an electric motor housed in a housing to move the throttle valve, both ends of a motor output shaft is configured to protrude from the housing in such a manner that the one end is connected to a power transmission mechanism, whilst the other end is inserted in a hollow boss formed in a fixing component of the motor, thereby ensuring no fluctuation to occur in the positional relation of the output shaft to the throttle shaft, while enabling to prevent friction from being generated in the power transmitting mechanism. In addition, a manual operating lever is provided to allow the engine to be easily started again even when the throttle valve is held nearly closed when the engine is stopped.

Abstract: A fault on the generator can be detected with the use of a simple arrangement. The output of the generator 12 which has multi-phase winding and is driven by an engine 11 is rectified and then converted by an inverter 133 into an alternating current at the frequency of a system before interconnected to the source of the system. After the engine 11 is started, the direct current voltage Vdc is monitored with a first fault monitor 40. When the direct current voltage Vdc rises up to a predetermined level, a connector relay 135 is closed. As the output of the inverter 133 is increased, the interconnection with the system source is enabled. After the interconnection, the direct current voltage and the output of the inverter are monitored with a second fault monitor 43. If the direct current voltage drops down to below the predetermined level before the output of the inverter reaches a rated level, the canceling and re-interconnection is repeated.

Abstract: A generator apparatus such as in a cogeneration system has a controlling power supply energized with its generator output with giving no adverse effect on the waveform of its output. An inverter 13 is provided for converting an alternating current output of the engine generator 10 into a direct current and returning back by the action of its inverter circuit 133 to an alternating current of a predetermined frequency which is then connected to a power supply system 14. While the engine 11 remains not actuated, a power received from a joint between the inverter 13 and the power supply system 14 is rectified by a rectifier 141 and transferred to the controlling power supply 140. When the engine 11 is started, the power at the input of the inverter circuit 133 is transmitted to the controlling power supply 140.

Abstract: A grid-type engine generator apparatus which can prevent reduction in the operational efficiency due to the stop motion of an engine at the cancellation of the interconnection and minimize loads exerted on the startup device for the engine. A network protector is provided for generating a fault signal when detecting a fault on the network source. Upon receiving the fault signal, an interconnection relay is opened to cancel the interconnection and simultaneously, a timer is started. The cancellation permits the engine to run with no load. When the fault signal is maintained until the setting duration of the timer is timed up, a time-out signal is released to stop the engine. On the other hand, when the fault signal is eliminated by canceling the cause of the fault before the setting duration of the timer is passed, the interconnection relay is closed to establish the interconnection again and the timer is reset.

Abstract: A control system for general-purpose spark-ignition internal combustion engine to be used for a portable generator, etc., having one or two cylinders and an actuator connected to the throttle valve to open or close the throttle value. In the system, an adaptive controller with a parameter identification mechanism is provided which receives a detected engine speed and a desired engine speed as inputs, and computes a command value to be supplied to the actuator, using an adaptive parameter identified by the parameter identification mechanism, such that the detected engine speed is brought to the desired speed. In the system, the desired engine speed is determined such that the desired engine speed per unit time is not greater than a prescribed value. and the command value is determined to be within the upper and lower limits of the throttle value. In addition, the detected engine speed is smoothed and a gain for determining the convergence speed of the adaptive controller is determined appropriately.

Abstract: A generator apparatus such as in a cogeneration system has a controlling power supply energized with its generator output with giving no adverse effect on the waveform of its output. An inverter 13 is provided for converting an alternating current output of the engine generator 10 into a direct current and returning back by the action of its inverter circuit 133 to an alternating current of a predetermined frequency which is then connected to a power supply system 14. While the engine 11 remains not actuated, a power received from a joint between the inverter 13 and the power supply system 14 is rectified by a rectifier 141 and transferred to the controlling power supply 140. When the engine 11 is started, the power at the input of the inverter circuit 133 is transmitted to the controlling power supply 140.

Abstract: This can prevent declination in the operational efficiency due to the stop motion of an engine at the cancellation of the interconnection and minimize loads exerted on the startup device for the engine. A system protector 138 is provided for generating a fault signal when detecting a fault on the system source. Upon receiving the fault signal, an interconnection relay 135 is opened to cancel the interconnection and simultaneously, a timer 39 is started. The cancellation permits the engine 11 to run with no load. When the fault signal is maintained until the setting duration of the timer 39 is timed up, a time-out signal is released to stop the engine 11. On the other hand, when the fault signal is eliminated by canceling the cause of the fault before the setting duration of the timer 39 is passed, the interconnection relay 135 is closed to establish the interconnection again and the timer 39 is reset.

Abstract: A fault on the generator can be detected with the use of a simple arrangement. The output of the generator 12 which has multi-phase winding and is driven by an engine 11 is rectified and then converted by an inverter 133 into an alternating current at the frequency of a system before interconnected to the source of the system. After the engine 11 is started, the direct current voltage Vdc is monitored with a first fault monitor 40. When the direct current voltage Vdc rises up to a predetermined level, a connector relay 135 is closed. As the output of the inverter 133 is increased, the interconnection with the system source is enabled. After the interconnection, the direct current voltage and the output of the inverter are monitored with a second fault monitor 43. If the direct current voltage drops down to below the predetermined level before the output of the inverter reaches a rated level, the canceling and re-interconnection is repeated.