Yamaha Hatsudoki Kabushiki Kaisha

Asahi Denso Co., Ltd.

Other

Haruhiko Samoto

Michiyuki Suzuki

Masahiro Kawamura

Norio Hayashi

Yoshiyuki Higaki

Yoshinobu Yashiro

Hideaki Nagasaka

Takeshi Matsuda

Tomoaki Kishi

Hirokazu Fujita

Harutomo Tozuka

Harokazu Fujita

A straddle type vehicle includes a protrusion which is displaced together with a throttle valve, a lever pulley which is displaced in response to the rotation of a throttle grip, a spring and a control device. The spring generates elastic force to return the protrusion to a first original position when the lever pulley is in a second original position. The spring maintains the lever pulley in the second original position by being elastically deformed until the protrusion reaches a predetermined position in which the protrusion is displaced from the first original position in such a direction that the throttle valve opens when the lever pulley is in the second original position. The control device opens the throttle valve by displacing the protrusion until the protrusion reaches the predetermined position in a gear shift change when the throttle grip is fully closed.

Straddle type vehicle

An electronic engine control unit for a motorcycle or other two-wheeled vehicle gradually decreases engine torque at the time of a failure so as to eliminate an uneasy feeling that an operator might experience if the engine torque were to be reduced abruptly. When a failure is detected, a throttle valve is closed gradually by initially closing the valve quickly and then slowly closing the valve so as to obtain a smooth decrease in engine torque. In addition, the ignition timing is changed gradually toward retardation to gradually decrease engine torque. Alternatively, the ignition pulses to the cylinders are thinned out gradually to cause a gradual decrease in engine torque. As a further alternative in the case of a multi-cylinder engine, the ignition pulses are stopped on a cylinder-by-cylinder basis to cause a gradual decrease in engine torque.

Electronic engine control device

A throttle-opening detecting apparatus has a case mounted on a handle bar of a vehicle, a throttle grip mounted on a leading end side of the handle bar from the case so as to be rotatable with respect to the handle bar, a detect member incorporated in the case and rotatable in linking with the throttle grip, a throttle-opening sensor for detecting the rotation angle of the detect member, and a rotative direction changing unit for rotating the detect member in a direction substantially perpendicular to the rotative direction of the throttle grip, so as to provide a throttle-opening detecting apparatus which can decrease the thickness-direction dimension of the case to thereby reduce the size of the throttle-opening detecting apparatus.

Throttle-opening detecting apparatus

A throttle-opening detecting apparatus has a case mounted on a handle bar of a vehicle, a throttle grip mounted on a leading end side of the handle bar so as to be rotatable with respect to the handle bar, a throttle-opening sensor incorporated in the case for detecting a rotation angle of the throttle grip and, a friction plate applying a frictional force in an opposite direction with respect to the rotation of the throttle grip to the throttle grip while the throttle grip is rotated so as to provide a throttle-opening detecting apparatus which not only can omit the throttle wire but also can obtain the rotation load of the throttle grip similar to the conventional throttle-opening detecting apparatus to thereby permit execution of the operation of the throttle grip without giving the driver a strange feeling.

A throttle-opening sensor has a detect shaft rotatable about an axis in conjunction with a throttle grip, a pair of rotation terminals respectively disposed on different positions in the same circle with the rotation axis, the pair of rotation terminals being rotatable together with the detect shaft, contact pieces disposed on each of the rotation terminals at predetermined intervals in a rotation-radius direction of the rotation terminal, a printed circuit including conducting pattern portions printed along sliding loci of the contact pieces and, a resistance portion printed in a sliding range of the contact piece of the conducting pattern portion, and generating a resistance against a current flowing in the conducting pattern portion, wherein at least two detection signals variable in mutually opposite directions according to the rotation angles of the throttle grip are generated due to that the contact pieces respectively allow the conducting pattern portions to conduct therebetween.

Throttle-opening sensor

A number of embodiments of engine induction system and fuel injection systems for increasing the engine's combustion efficiency by maintaining a desired ratio between the intake system volume between the throttle valve and the intake port and the exhaust gas volume. This requires a close positioning of the throttle valve to the combustion chamber, and thus results in quick throttle response. A fuel injection system injects fuel into the intake passage, and a number of embodiments of buffer valves are employed so as to maintain stability in combustion when blipping the throttle under no-load conditions. In addition, arrangements are disclosed wherein separate throttle bodies are employed but that utilize the fuel rail as a means for connecting all of these throttle bodies together to provide a unitary sub-assembly. In addition, an improved throttle position sensor and associated controls are mounted in close proximity to each other on the throttle bodies in many of the embodiments in order to reduce external wiring and improve signal transmission. In addition, the control system employs an arrangement for compensating for a non-linearity in the output of the throttle position sensor.

Induction system for fuel injected engine

A number of embodiments of engine induction system and fuel injection systems for increasing the engines combustion efficiency by maintaining a desired ratio between the intake system volume between the throttle valve and the intake port and the exhaust gas volume. This requires a close positioning of the throttle valve to the combustion chamber, and thus results in quick throttle response. A fuel injection system injects fuel into the intake passage, and a number of embodiments of buffer valves are employed so as to maintain stability in combustion when blipping the throttle under no-load conditions. In addition, arrangements are disclosed wherein separate throttle bodies are employed but that utilize the fuel rail as a means for connecting all of these throttle bodies together to provide a unitary sub-assembly. In addition, an improved throttle position sensor and associated controls are mounted in close proximity to each other on the throttle bodies in many of the embodiments in order to reduce external wiring and improve signal transmission. In addition, the control system employs an arrangement for compensating for a non-linearity in the output of the throttle position sensor.

Growing community of inventors

Shizuoka, Japan

Haruhiko Samoto