Yamaha Hatsudoki Kabushiki Kaisha

Hidetoshi Kageyama

Junichi Kaku

Kimitake Otome

Hideo Fujita

Kenji Komatsu

Nobuaki Karaki

A compact supercharged internal combustion engine, wherein the supercharger is mounted above the twin overhead cam cylinder head of the engine but is readily detachable from it. The drive for the pumping elements of the supercharger including counter rotating shafts to which balance masses are added so as to assist in engine balancing. In addition to supplying compressed air to the combustion chambers of the engine for combustion, the supercharger also supplies air to an air injection system that cooperates with the exhaust system for reducing the emissions of undesirable pollutants to the atmosphere.

Supercharged engine

The present invention is an injection system including an injection device. The injection device includes a pumping chamber and an electrically operated device associated with the pumping chamber which, when energized, is capable of providing a rapid increase in localized fluid pressure in said pumping chamber without reciprocating a piston in a cylinder bore. A discharge port associated with the pumping chamber permits discharging of fluid displaced by the localized pressure increase. The injection system includes a circuit providing an energizing voltage to the electrically operated device, and a control for changing at least one characteristic of the energizing voltage selected from the group consisting of: the peak energizing voltage, the rate at which said energizing voltage increases, the rate at which said energizing voltage decreases, the duration of energization, and the frequency of energization.

Fuel injection system

A cylinder head constructions wherein the cylinder head is comprised of a main cylinder head member that slidably supports the valves for the engine, and which has an upper peripheral edge that defines a cam chamber. At least one camshaft and the tappets associated thereby are supported by a separate cam and tappet carrier member that is affixed to the main cylinder head member. The bearing surfaces for the camshaft are formed at longitudinally spaced points and the valves for the corresponding cylinder are disposed between those points and are in parallel relation but have a large diameter and their actuating tappets have a large diameter but do not encroach on the bearing surfaces for the camshaft.

Cam and tappet carrier for engine

A fuel injection system is provided with an interior pumping chamber (94) which is connected to a fuel inlet (98). A pumping element (90) is provided with piezoelectric elements (124) which are interspaced between electrodes (126, 128). The pumping element (90) is electrically connected to an ECU (58). Activation of the piezoelectric elements causes pumping element (90) to expand and thereby impart pressure from a pressure surface (112) which extends into the pumping chamber (94). Fuel in the pressure chamber, as a result of the piezoelectric elements is pushed from the pressure chamber and through an injection valve (116). The applicants are reminded that formal drawings are now required. Further, as noted in the Office Action of Dec. 16, 1999, in FIG. 2, numeral 124 should be changed to indicate mounting plate 121. On drawing sheet 6, FIG. 6a and FIG. 6b should be indicated.

Growing community of inventors

Iwata, Japan

Hidetoshi Kageyama