Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Tokyo Seat Corp., Ltd.

Honda Giken Hogyo Kabishiki Kaisha

Hiroshi Moriyama

Takashi Suzuki

Takanori Sato

Toru Taniguchi

Yoshikazu Sato

Tetsuya Arai

Akihisa Shinoda

Makoto Yonezawa

Ryuhei Tamamoto

Tatsuya Tokuda

Masayuki Sasaoka

Kenzo Shimada

Hiroaki Kojima

Makoto Warashina

Shigeru Saito

Shigeki Edamatsu

Dominique Vougier

Kazuo Shimizu

Fumio Ogata

Jun Hosaka

Shingo Yoneda

Iwao Miyajima

A cleaner cover replacing method includes the steps of detaching a first cleaner cover from a cleaner case; placing an attachment into fitted engagement with claw hooking parts of the cleaner case, placing a second cleaner cover on the cleaner case, and causing a bolt to pass through a bolt hole of the second cleaner cover and to threadedly engage with a nut part of the attachment.

Replacement of air cleaner cover

A walk-behind working machine includes a first clutch mechanism for connecting or disconnecting drive between an engine and a working member of the working machine. The first clutch mechanism includes a first clutch lever having a first activating member. A second clutch mechanism is configured to connect or disconnect drive between the engine and traveling members of the working machine. The second clutch mechanism includes a second clutch lever having a second activating member. A throttle regulating mechanism has a pivoting member for engagement with one of the first activating member of the first clutch mechanism and the second activating member of the second clutch mechanism so as to undergo pivotal movement to shift a throttle for the engine from a first opened position in which an idling engine speed is produced to a second opened position in which a working-machine-activating engine speed is produced.

Walk-behind working machine throttle control

An air cleaner has a casing body having an opening that communicates with a carburetor. The casing body includes a fitting part having an inner wall surface and a bearing surface. A sealing frame is inserted into the casing body and engages the fitting part of the casing body. The sealing frame has an outer peripheral part with an outer peripheral surface that is held in contact with the inner wall surface of the fitting part, a rear surface that is held in contact with the bearing surface of the fitting part, a front surface, and a groove formed in the front surface along a circumference thereof. A filter is disposed internally of the sealing frame. A cover covers the filter and the sealing frame.

Air cleaner

A carburetor automatic control system in an engine includes, a temperature-sensitive operating device for operating a choke valve so that the choke valve is opened with a temperature increase of the engine and a governor for opening and closing a throttle valve to maintain a preset rotational speed of the engine. The governor device includes, a stepping motor opening and closing the throttle valve over a range from an idling opening degree to a fully opening degree, and an electronic control unit driving the stepping motor so that the rotational speed of the engine is maintained the preset speed. A relief mechanism is interposed between the choke valve and the temperature-sensitive operating device, the relief mechanism opening the choke valve in response to an intake vacuum pressure within the intake passage when the engine is in a cold state and the choke valve is in a fully closed state.

Carburetor automatic control system in engine

An engine decompression system that can secure a projecting height of a decompression cam from a base face of a valve operating cam to be relatively large in an engine starting rotational region, and maintain a state in which the projection height is decreased in a complete combustion rotational region of the engine. The decompression system includes a decompression cam shaft provided on a valve operating cam shaft or a rotating member integrally coupled thereto, the decompression cam shaft being capable of rotating between an operating position in which a decompression cam projects above a base face of a valve operating cam to slightly open engine valves during a compression stroke and a release position in which the decompression cam is withdrawn to allow the engine valves to close. A centrifugal mechanism connected to the decompression cam shaft maintains the decompression cam shaft at an operating position in a starting rotational region, and rotates the decompression cam shaft to the release position in a normal running region. The centrifugal mechanism is arranged so that, in a complete combustion rotational region between the starting rotational region and the normal running region, the decompression cam shaft is maintained at a middle position at which the projection height of the decompression cam is less than the projection height at the operating position.

Engine decompression system

A carburetor valve control system for stabilizing engine warm-up operating conditions by automatically controlling the degree of opening of a throttle valve so as to be larger than a normal degree of opening for idling, without carrying out a special operation of appropriately strengthening the spring force of a governor spring. The carburetor throttle valve control system includes a throttle lever and a governor system coupled to the throttle lever. A choke return spring is connected to a choke lever, the choke return spring urging the choke lever to a choke valve closing side. An automatic choke system is disposed so as to face the choke lever. A throttle valve closure restricting member is provided between the throttle lever and the choke lever. During engine warming-up, when the spring force of a governor spring is adjusted to zero or a minimum, the choke lever restricts closing of the throttle valve via the throttle lever by means of the spring force of the choke return spring.

Carburetor throttle valve control system

In a fuel tank system, a strainer chamber with a suction bore opened into its upper surface is provided in a collecting recess for collecting a residual fuel containing impure foreign substances such as dust and water, the collecting recess being provided in a bottom wall of a fuel tank. A fuel discharge pipe is connected to the strainer chamber. Fuel flow passages are provided outside the strainer chamber. Baffle plates are provided in front and in the rear of and outside the strainer chamber to guide the fuel flowing into the collecting recess during tilting of the fuel tank into the fuel flow passages. Thus, the impure foreign substances are prevented from entering the strainer chamber.

Fuel tank system

An automatic choke system includes: a wax-type temperature sensing section; and an output section which opens a choke valve of a carburetor in response to heat receiving operation of the temperature sensing section. Temperature sensing section includes: a bottomed cylindrical housing attached to an engine with its bottom portion directed to a high-temperature portion of the engine; a bottomed movable cylinder; a stationary piston slidably supported by the movable cylinder and having one end protruding out of the movable cylinder; and a wax contained in the movable cylinder in a sealed manner, and causing the movable cylinder and the stationary piston to move relative to each other in an axial direction. The movable cylinder is slidably housed in the housing in a state in which an outer end of the stationary piston abuts against an inner surface of the bottom portion of the housing. The output section is connected to the movable cylinder. Thus, the rate of opening of the choke valve can be increased immediately after the start of engine warming-up operation, and reduced as approaching the completion of engine warming-up operation.

Automatic choke system for carburetor

A device for controlling a choke valve of a carburetor for an engine includes: a choke closed state hold device for holding, in a closing position, a choke lever urged by a spring in a direction for opening the choke valve, when the choke lever is turned to the closing position, the choke closed state hold device releasing the choke lever from the held state by a throttle operation thereafter performed; a control lever which turns between a low-temperature position and a high-temperature position, and which at its low-temperature position limits the position of the choke lever released from the choke closed state hold device to an intermediate position and at its high-temperature position limits the position of the choke lever to an opening position; a first control spring which urges the control lever toward the low-temperature position; and a second control spring which is made of a shape memory alloy, and which turns the control lever to the high-temperature position when the engine temperature reaches a predetermined high temperature. With this arrangement, the opening of the choke valve is controlled in a rational way according to changes in engine temperature, to thereby stabilize warm-up operation and improve the fuel consumption rate.

Device for controlling choke valve of carburetor

A device for controlling a choke valve of a carburetor for an engine, includes a choke closed state hold device for holding, in a closing position, a choke lever connected to the choke valve of a carburetor and urged by a spring in a direction for opening the choke valve, when the choke lever is turned to the closing position, the choke closed state hold device releasing the choke lever from the held state by a throttle operation of the carburetor after a start of the engine. The choke closed state hold device includes a lock arm provided continuously with a throttle lever and a locked arm provided continuously with the choke lever, the lock arm and the locked arm elastically surmounting each other when the choke lever is turned to the closing position in a state where the throttle lever is in the opening position corresponding to a full open position of the throttle valve, so that the lock arm prevents the locked arm from turning back. Thus, the choke closed state hold device is constituted only by the lock arm and the locked arm respectively provided continuously with the throttle lever and the choke lever, and there is no need for a lock lever specially supported axially on the carburetor as in the conventional arrangement. Therefore, the number of components is reduced, and the construction is simplified, so that the manufacturing cost of the choke valve control device can be reduced.

A choke valve control system includes a choke-operating lever for opening and closing a choke valve of a carburetor, a choke spring for biasing the valve in an opening direction, and a damper for controlling the opening motion of the valve to a lower speed, when the choke valve is opened from its fully closed position by a biasing force of the choke spring. The choke-operating lever, the choke spring and the damper are connected to the choke valve of the carburetor. In this choke valve control system, the damper includes a damper housing, a rotor, and a damper oil which is accommodated in a sealed manner in the damper housing and applies a viscosity resistance to the rotation of the rotor, which resistance increases as the viscosity increases with decreasing temperature. Thus, the time required for opening the choke valve can be controlled in accordance with the level of the environmental temperature of an engine, thereby providing the stabilization of the warming operation of the engine and a reduction in fuel consumption.

Control system for choke valve of carburetor

An engine lubrication system has an arrangement in which the base of a crankcase is used to form an oil reservoir, and a part of an oil slinger that is driven by a crankshaft via a transmission system is immersed in the oil within the oil reservoir. An oil pump that is driven by the transmission system is immersed in the oil within the oil reservoir, and a discharge port of the oil pump communicates with a lubricating-oil passage within the crankshaft. It is thereby possible to provide an engine lubrication system based on a splash-type lubrication system while at the same time using a forced-type lubrication system, thus reducing the capacity of the oil pump and simplifying the drive system, and effectively suppressing an increase in the overall cost.

Engine lubrication system

A V-2 engine includes two cylinder blocks mounted to a crankcase such that the respective cylinder axes of the cylinder blocks extend at an angle to each other and merge together at the axis of a crankshaft with the angle formed between the cylinder axes being divided into two angle parts by a centerline of the crankcase passing through the axis of the crankshaft, and an auxiliary machine mounted to the crankcase on the same side as one of the cylinder blocks when viewed from the axis of the crankshaft. In order to reduce the maximum width of the engine, the cylinder blocks are offset from a symmetric position with respect to the centerline of the crankcase to such an extent that a straight line circumscribing an outer end of a head cover attached to the one cylinder block and an outer end of the auxiliary machine is in parallel to the centerline of the crankcase.

V-2 engine

An overhead camshaft V-2 engine includes a single power transmitting mechanism disposed on one side of a crankcase for transmitting rotational power from a crankshaft to respective camshafts of drive valve mechanisms. The power transmitting mechanism has a driving member mounted to only one end portion of the crankshaft. The thus arranged power transmitting mechanism enables downsizing of the engine. Two intake ports are formed in respective cylinder heads of two cylinder blocks and open at one end to respective first surfaces of the cylinder heads facing in a first direction, and two exhaust ports are formed in the respective cylinder heads of the cylinder blocks and open at one end to respective second surfaces of the cylinder heads facing in a second direction opposite to the first direction. With this arrangement of the intake and exhaust ports, intake pipes can be arranged with a high degree of freedom.

Overhead camshaft V-2 engine

A riding-type powered lawn mower has a frame, front and rear wheels rotatably mounted on the frame, an engine mounted on the frame for rotating the rear wheels, a cutter deck mounted on the frame and housing a cutter blade drivable by the engine, a driver's seat mounted on the frame by a seat bracket in front of the engine, and a steering column mounted on the frame forwardly of the driver's seat. The riding-type powered lawn mower also has a body paneling mounted on the frame. The body paneling comprises a unitary front body cover covering the steering column, the seat bracket, and a front portion of the engine, and a unitary rear hood detachably connected to a rear end of the front body cover and covering a rear portion of the engine.

Growing community of inventors

Saitama, Japan

Hiroshi Moriyama