Yamaha Hatsudoki Kabushiki Kaisha

Yoshiharu Yokoyama

Shigeru Akiyama

Tsuyoshi Kamiya

Nobuyuki Kanno

Hironori Nakayama

Takeshi Nagase

Izumi Yamashita

Kazuhito Kitano

A gasoline engine power assisted pedal operated vehicle. The amount of assist provided by the engine is varied in response to variations in the manual force applied by the operator to the pedal mechanism. However, in order to provide smoother power assist, rapid changes in manual power application and, specifically, rapid reductions are dampened in the engine response. In addition, the system includes a disabling device for disabling the connection between the engine and the vehicle propulsion system if the vehicle brakes are actuated.

Sensor for bicycle with assist engine

Several embodiments of prime mover-assisted pedal-operated vehicles, such as a bicycle. In each embodiment, both the prime mover and the pedal mechanism drive the rear wheel through a common transfer shaft. The transfer shaft is disposed vertically above the pedal-operated crankshaft axis so as to improve the ground clearance and simplify the overall construction of the bicycle. The transmission arrangement is such that the prime mover transmission ratios are always in a step-down condition while the pedal-operated crankshaft drives the transfer shaft through a step-up transmission. Various embodiments of improved torque sensors are also employed so as to provide smooth transition and smooth feel to the rider.

Power assisted bicycle

Bicycle with assist engine

A compact portable electrical generator powered by a gas fueled internal combustion engine. A combined starter and generator is coupled to the engine for starting of the engine and for generating electrical power when the engine is running. The engine includes a lubricating system including lubricant that is supplied from a separately insertable lubricant cartridge and which is pumped by a hose compressing type of pump so as to insure adequate delivery of small amounts of lubricant regardless of the orientation of the unit and also so as to insure that lubricant cannot leak from the system when the unit is not being operated.

Compact power supply and lubricant affording device therefor

A number of embodiments of small lightweight outboard motors adapted to be mounted on a watercraft that does not have a transom through a mounting bracket that spans the sides of the hull and is detachably affixed thereto. The outbaord motor is powered by small internal combustion engine that is contained within the lower unit and at least partially submerged beneath the body of water in which the watercraft is operating. Excess cooling of the engine is avoided by circulating at least a portion of the exhaust gases from the exhaust port around the exterior of the internal combustion engine. The engine is powered by a gaseous fuel contained under pressure in a container that is mounted on the mounting portion. Variations in placement and orientation of pressure regulators are disclosed so that fuel pressure will be constant regardless of the trim adjustment of the outboard motor. In addition, the connection between the outboard motor and the mounting bracket is such that the outboard motor may be easily swung from the suspended position in the water to an out-of-the-water position within the hull.

Outboard motor

Several embodiments of gaseous fuel supplying systems for an internal combustion engine used to power a portable generator. In each embodiment, heat is supplied to the fuel so as to maintain the fuel pressure if the fuel pressure falls below a predetermined pressure. In some embodiments, the heat supply is on-off and in other embodiments it is variable. In certain embodiments, the heat is supplied electrically and in another embodiment, the heat is extracted from the engine. In addition, one embodiment incorporates a cold starting arrangement wherein fuel is supplied to the engine for cold starting at full container pressure.

Fuel supplying system for gas engine

A small portable generator powered by a gas fueled internal combustion engine. The gas fuel supply system for the engine includes a solenoid value whose duty cycle is regulated so as to permit unthrottled operation of the engine and afford engine speed control.

Gas engine

A fuel supply and glow plug arrangement for a portable electrical power supply fueled by a gaseous fuel internal combustion engine. The gaseous fuel flow to the engine is controlled by a solenoid valve having its duty cycle varied to vary engine speed. In addition, the solenoid valve is shut off when the engine speed falls below a predetermined speed so as to prevent fuel leakage. The engine is fired by a flow plug which is supplied with power at a high power level during cranking and at a lower power level during running.

Gas powered engine with glow plug ignition

A compact power supply powered by a gas fueled internal combustion engine having a liquid cooling system. The liquid cooling system includes an expandable expansion chamber device which permits a compact construction and which also permits the use of a cooling system that is devoid of any air.

Growing community of inventors

Iwata, Japan

Yoshiharu Yokoyama