Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Shinji Saito

Hayato Maehara

Takaaki Tsukui

Kazuhito Hotta

Masahiro Kuroki

Kenichiro Nakamura

Akifumi Nomura

Toru Gunji

Satoru Nojima

Yukihiro Asada

Takeru Abe

Yukihiro Tsubakino

Masaya Adachi

Masaji Narushima

Shunsuke Kitawaki

Norimasa Hattori

An internal combustion engine which includes a valve deactivation mechanism for reducing an output power shock upon changing of the cylinder number. In an internal combustion engine which includes a valve deactivation mechanism driven by a slide pin which is driven by hydraulic pressure, response delay time after a signal is sent to oil control valves until an intake valve and an exhaust valve are activated or deactivated is used to form a control map in response to control parameters, and the valve deactivation mechanism is controlled based on the control map.

Internal combustion engine including valve deactivation mechanism

A hydraulic pressure warning system for an internal combustion engine including a hydraulic pressure sensor that is prevented from being influenced by the heat of the engine and by the pulsation of an oil pump. A hydraulic pressure sensor detects hydraulic pressure in a lubricating oil passage of the engine and issues a warning based on hydraulic pressure detected by the hydraulic pressure sensor when the hydraulic pressure drops. The hydraulic pressure sensor is provided on a wall surface of a water jacket of a rear cylinder block so as to project therefrom.

Hydraulic pressure warning system for internal combustion engine

A multicylinder engine for a motorcycle includes a valve actuation mechanism having a hydraulically-operated valve pausing mechanism for holding at least one of an intake valve and an exhaust valve of selected cylinders in a suspended state. The valve actuation mechanism operates the intake valve and the exhaust valve, and controls flow of oil through an oil passage which introduces working oil to the valve pausing mechanism from a hydraulic-pressure control device. Air-bleeding holes are formed in the cylinder head. The air-bleeding holes are fluidly connected with portions of the oil passages that are located at a highest level in the oil passages while the motorcycle is parked in an inclined state with its side stand down.

Multicylinder engine for a vehicle, and vehicle incorporating same

A valve stopping mechanism wherein when hydraulic fluid pressure is low a cylinder operating state is set and a response of a switch from a cylinder stop state to the cylinder operating state is high. An intake valve and an exhaust valve, a first intake valve spring and a first exhaust valve spring are provided for energizing the valves in the direction of closing the valves, valve drive cams, valve stopping mechanisms, on the basis of a stop hydraulic fluid pressure and energization of plunger springs, for selectively generating valve operating and valve stop states. The valve stopping mechanism generates the operating state when the energizing force of the plunger spring is larger than the press force of the stop hydraulic fluid pressure and generates the stop state when the press force of the stop hydraulic fluid pressure is larger than the energizing force of the plunger spring.

Engine

A cooling control unit for a water-cooled multi-cylinder internal combustion engine having a cylinder deactivation mechanism for controlling the flow of coolant to prevent the internal combustion engine from being incompletely warmed up when the internal combustion engine returns to its operating condition with all of the cylinders being activated. A communicating passage communicates with a normally activated cylinder coolant jacket as a coolant passage formed for normally activated cylinders and a deactivation-programmed cylinder water jacket as a coolant passage formed for the deactivation-programmed cylinders to communicate with each other, and through which the coolant flows. A bypass passage diverges from the communicating passage and bypasses the deactivation-programmed cylinder coolant jacket. A diversion control valve is provided in a diversion section where the bypass passage diverges from the communication passage. A control member controls the diversion control valve in accordance with the operating state of the internal combustion engine.

Cooling control unit for water-cooled multi-cylinder internal combustion engine having cylinder deactivation mechanism

In a V-type engine for a vehicle, in which a hydraulic valve rest mechanism which selectively holds at least one of an intake valve and an exhaust valve corresponding to a part of plural cylinders in a valve-closed rest state in correspondence with a vehicle running status is provided in a valve actuation unit, and a hydraulic controller which controls hydraulic pressure of the valve rest mechanism is provided in a main engine body, to reduce the distance of oil passage from the hydraulic controller to the hydraulic valve rest mechanism and simplify the structure of the oil passage. A hydraulic controller is provided on at least one side surface of a cylinder head, and may be generally oriented along a line which is substantially parallel to a central axis of a cylinder bore.

V-type engine and motorcycle incorporating same

A motorcycle engine includes a crankcase housing a crankshaft, and a transmission unit therein, a cylinder block disposed above the crankcase, a cylinder head disposed above the cylinder block, and an intake system arranged behind the cylinder head, and a knock sensor arranged on an upper surface of the crankcase. The knock sensor is arranged behind the cylinder head, and disposed between the intake system and the cylinder block, such that the knock sensor does not restrict arrangement of additional functional parts of the engine on an upper surface of the crankcase. The knock sensor is substantially surrounded and protected by the intake system, the cylinder head, the cylinder block and the crankcase.

Positional arrangement of knock sensor on a motorcycle engine

In a variable valve timing mechanism, a valve-lifting cam member is fitted, slidably in the circumferential direction, onto a camshaft that is driven to rotate in synchronization with a crankshaft of a four-stroke cycle internal combustion engine. An eccentric collar is set between a driving collar fixed on the camshaft and the valve-lifting cam member. A driving projection is formed in the driving collar and engages with one of sandwiching portions of the eccentric collar. A driven protrusion is formed in the valve-lifting cam member and engages with another one of the sandwiching portions of the eccentric collar. A linkage mechanism includes the eccentric collar, the drive, and the driven protrusions. The variable valve timing mechanism adjusts the timing of opening and closing of the valve while the rotational phase of the valve-lifting cam member is cyclically varied relative to the camshaft by the eccentricity of the eccentric collar.

Variable valve timing mechanism

A V-type vehicle engine includes a main engine body with a front bank with a rear bank defining a V-type structure. A plurality of valve actuation units are respectively located in valve chambers in the front bank and the rear bank, to minimize the size of a cylinder head and a cylinder head cover in at least one of the front bank and the rear bank. A first valve actuation unit, with a double overhead camshaft structure having intake-side and exhaust-side camshafts individually corresponding to the intake valve and the exhaust valve, is located in a valve chamber in one of the front bank and the rear bank. A second valve actuation unit, having a common single camshaft for the intake valve and the exhaust valve, is located in a valve chamber in the other one of the front bank and the rear bank.

In a multi-cylinder engine provided with a cylinder pausing function, a hydraulically-operated valve-pausing mechanism is capable of selectively suspending operation of at least one intake or exhaust valve of one or more selected cylinders, depending on engine operating conditions, such that the suspended valve is temporarily held in a closed state. A hydraulic-pressure control device, for controlling hydraulic pressure supplied to the valve-pausing mechanism, is disposed on an engine body so as to minimize an amount of protrusion of the hydraulic-pressure control device from the engine body, while situating the hydraulic-pressure control device near the valve-pausing mechanism. A recess portion is formed on an external surface of a cylinder head or a head cover, and the hydraulic-pressure control device is disposed on the engine such that at least part of the hydraulic-pressure control device is accommodated in the recess portion.

Multi-cylinder engine with cylinder pausing function

A multicylinder internal combustion engine, which can simplify its control and is advantageous against thermal loads or vibrations includes a cylinder head with intake valves and exhaust valves arranged therein. Valve actuators are provided for openably operating the intake valves and exhaust valves, respectively. A cylinder head cover forms, in combination with the cylinder head, a valve actuator chamber with the valve actuators accommodated therein. At least some of the valve actuators are deactivatable to disable their corresponding cylinders. The multicylinder internal combustion engine is a V-shaped internal combustion engine provided with a front bank and rear bank. The cylinders on opposite ends in a direction of a crankshaft are set as full-time operating cylinders.

Multicylinder internal combustion engine

A variable valve operating mechanism of a four-stroke internal combustion engine includes a slide pin energized by a pin spring in a direction while oil pressure acting on the slide pin in the opposite direction through oil pressure supply passages. The slide pin moves by controlling the oil pressure causing a stem contact surface and a stem through hole to selectively face a valve stem. The mechanism also includes an oil discharge passage including a discharge port which is opened to allow oil acting the slide pin to be discharged when the valve lifter is pressed by a valve operating cam to move for opening the valve. The mechanism is capable of quickly moving the slide pin upon the release of oil pressure when the valve comes into a quiescent state. Therefore, the response of transitioning the variable valve from an operating state to the quiescent state is improved.

Variable valve operating mechanism of four-stroke internal combustion engine

An internal combustion engine having cylinders capable of selectively resting during engine operation is capable of eliminating step increases in engine output when the number of operative cylinders is changed. The internal combustion engine includes a plurality of cylinders divided into two or more groups, at least some of the cylinders being restable. A throttle valve of each of the cylinders is independently operable on the basis of the group to which the cylinder belongs, and the number of resting cylinders is controlled according to the throttle grip opening. The throttle valve opening is different between the groups, except for the full opening condition and the full closure condition of the throttle valve, and an ECU is provided for opening the throttle valve of the next cylinder group before the throttle valve opening of the former cylinder group reaches the full opening condition.

Internal combustion engine capable of selectively resting certain cylinders during low-load operation, and method of using same

An internal combustion engine incorporating rest cylinders is provided which does not need a high response performance when operating a throttle valve and which can eliminate engine output variations as the number of operable cylinders changes. In the internal combustion engine, some of a plurality of cylinders is configured to rest during normal operation of the engine. The cylinders are divided into a plurality of cylinder groups, and each of the cylinders is provided with an independent throttle valve. An ECU for increasing the number of operative cylinder groups according to at least the throttle handgrip opening is provided. Also provided are motors for bringing the throttle valves in the cylinder in the rest state into a fully closed state on the basis of each cylinder group, a throttle valve position sensor, and the like.

A throttle body for controlling a plurality of throttle valves in a multi-cylinder engine. The throttle valves of at least two of the cylinders are structurally connected to each other.

Growing community of inventors

Saitama, Japan

Shinji Saito