Abstract: A mouth cavity sanitary device comprising: an outer case formed in a cylindrical shape so as to be capable of being held by one hand; an elongated drive unit detachably accommodated in the outer case from a lower portion, the drive unit having a pump thereof disposed in a lower portion of the outer case; a battery detachably accommodated in the outer case from also the lower portion so as to run parallel to the drive unit, the battery being electrically connected to the motor of the drive unit; a reservoir chamber formed from the upper portion of the outer case to the portion in which the drive unit and the battery are respectively accommodated, the reservoir chamber being connected to the suction side of the pump; and a nozzle the base portion of which is detachably fastened to the upper portion of the outer case, the nozzle being connected to the discharge side of the pump.

Abstract: The invention provides a power transmitting system for a small boat, such as a water jet propulsion craft, and more particularly, an improved arrangement for connecting an engine output shaft to a propulsion unit input shaft. Also provided is an arrangement for balancing an engine within the craft against undesirable operational forces tending to render the craft unstable. The connecting assembly includes a coupling arrangement utilizing elastomeric vibration dampening members. One of the dampening members possesses a high degree of elasticity, while another of the dampening members possesses a low degree of elasticity. A durable, yet efficient vibration dampening coupling arrangement, which is additionally able to act as a universal joint, is thereby achieved. The engine balancing arrangement includes a flywheel which rotates in response to the crankshaft assembly of the engine.

Abstract: A mouth cavity sanitary device comprising: an outer case formed in a cylindrical shape so as to be capable of being held by one hand; an elongated drive unit detachably accommodated in the outer case from a lower portion, the drive unit having a pump thereof disposed in a lower portion of the outer case; a battery detachably accommodated in the outer case from also the lower portion so as to run parallel to the drive unit, the battery being electrically connected to the motor of the drive unit; a reservoir chamber formed from the upper portion of the outer case to the portion in which the drive unit and the battery are respectively accommodated, the reservoir chamber being connected to the suction side of the pump; and a nozzle the base portion of which is detachably fastened to the upper portion of the outer case, the nozzle being connected to the discharge side of the pump.

Abstract: An arrangement is provided for variably adjusting the effective flow area along a region within a water injection propulsion unit. The invention is adapted to be embodied in a small watercraft of the type that is designed to be operated by a single rider sitting in straddle fashion on the watercraft. The flow area adjustments may be made in response to the value of a selected operating variable, or several variables, which may be measured during the operation of the watercraft. The invention allows attainment of optimum accelerability at low to medium speeds, and optimum accelerability and top speed at high speeds.

Abstract: A number of embodiments of exhaust systems for marine watercraft, particularly, those of the jet propelled type. The exhaust systems all include an exhaust pipe which terminates in a discharge opening formed in a lower surface of the hull for discharging exhaust gases through the body of water in which the watercraft is operating. In addition, the exhaust pipe has an ascending and descending section with an expansion chamber communicating with the upper portion thereof through an opening so as to accumulate water if the watercraft becomes inverted and to direct the accumulated water back to the exhaust outlet opening when righted so as to preclude water from flowing to the exhaust ports of the engine. The expansion chamber also acts as a silencing device and may comprise a portion of a Helmholtz resonator.

Abstract: A mouth cavity sanitary device comprising: an outer case formed in a cylindrical shape so as to be capable of being held by one hand; an elongated drive unit detachably accommodated in the outer case from a lower portion, the drive unit having a pump thereof disposed in a lower portion of the outer case; a battery detachably accommodated in the outer case from also the lower portion so as to run parallel to the drive unit, the battery being electrically connected to the motor of the drive unit; a reservoir chamber formed from the upper portion of the outer case to the portion in which the drive unit and the battery are respectively accommodated, the reservoir chamber being connected to the suction side of the pump; and a nozzle the base portion of which is detachably fastened to the upper portion of the outer case, the nozzle being connected to the discharge side of the pump.

Abstract: A mouth cavity sanitary device comprising: an outer case formed in a cylindrical shape so as to be capable of being held by one hand; an elongated drive unit detachably accommodated in the outer case from a lower portion, the drive unit having a pump thereof disposed in a lower portion of the outer case; a battery detachably accommodated in the outer case from also the lower portion so as to run parallel to the drive unit, the battery being electrically connected to the motor of the drive unit; a reservoir chamber formed from the upper portion of the outer case to the portion in which the drive unit and the battery are respectively accommodated, the reservoir chamber being connected to the suction side of the pump; and a nozzle the base portion of which is detachably fastened to the upper portion of the outer case, the nozzle being connected to the discharge side of the pump.

Abstract: A number of embodiments of exhaust silencers for marine propulsion units including an exhaust device having a first expansion chamber, a pair of second expansion chambers and a third expansion chamber all formed within a common housing. The flow of exhaust gases is from the exhaust of the engine into the first expansion chamber, directly from the first expansion chamber into each of the pair of second expansion chambers and directly from the second expansion chambers to the third expansion chamber. In all embodiments the flow from the second expansion chambers to the third expansion chamber is in confronting relationships so as to improve silencing. In one embodiment, the second expansion chambers have different effective volumes so as to provide an extended range of tuning for the silencing.

Abstract: A number of embodiments of engine spark control systems wherein the engine speed is reduced in response to the sensing of an abnormal or an external condition and wherein the spark timing is altered when the spark is interrupted to preclude the likelihood of backfiring in the exhaust system or firing back in the induction system. In some embodiments, the sensed condition is an abnormal running condition and in other embodiments the sensed condition is shifting of the transmission. The backfiring and firing back is precluded primarily by advancing the spark from the idle spark advance.