Honda Giken Kogyo Kabushiki Kaisha

Asahi Denka Kogyo Kabushiki Kaisha

Mitsuharu Tanaka

Hiroshi Mizuguchi

Tomonori Ikuma

Hiroyuki Yoshida

Masaki Tsunoda

Hideaki Takada

Kenji Ikeda

Akihisa Saito

Hiroshige Kohno

Yoshihiko Fukuda

Kazuyuki Shiomi

Nobuo Suzuki

Takao Aihara

Hiroshi Kawamura

Kazuomi Kiku

Kazunori Kikuchi

Fumiko Irie

Kouji Yasuda

A decompressing mechanism (D) for an internal combustion engine (E) is incorporated into a camshaft () provided with a bore () extending in the direction of the arrow (A) along the axis (L) of rotation of the camshaft (). The decompressing mechanism (D) includes a decompression member () formed by metal injection and integrally having a flyweight (), a decompression cam () for exerting a valve-opening force through an exhaust rocker arm () on an exhaust valve, and an arm () connecting the flyweight () and the decompression cam (). The flyweight () is supported for swing motion by a pin () on the camshaft (). The axis (L) of swing motion of the flyweight () is included in a plane (P) substantially perpendicular to the axis (L) of rotation, and does not intersect the axis (L) of rotation and the bore () of the camshaft (). The fully expanded decompression member () revolves in a cylindrical space of a small diameter around the camshaft ().

Internal combustion engine provided with decompressing mechanism and method of adjusting valve lift for decompression

A decompressing mechanism included in an internal combustion engine has a flyweight supported for swinging motion by a pin on the camshaft of the internal combustion engine, a decompression cam and an arm connecting the flyweight and the decompression cam and having the shape of a plate. The flyweight has a weight body and projections projecting from the weight body and engaged with the pin. The weight body is a block of a width along the axis of swinging motion and a thickness, along a radial direction, which are greater than the thickness, along the axis, of swinging motion of the arm. The weight body overlaps the camshaft as viewed from a direction perpendicular to a reference plane. The decompressing mechanism is small, lightweight and is capable of concentrating most of its mass on the flyweight.

Internal combustion engine provided with decompressing mechanism

In a water-cooled outboard marine engine, a heat transfer portion is provided in an exit passage located between an outlet end of a cylinder water jacket and a cooling water outlet passage at a position upstream of the thermostat valve. Thus, when the thermostat valve has opened and the cooling water expelled from the water jacket via the thermostat valve has been replaced by freshly introduced cooling water, the heat transfer portion having a certain heat capacity warms the freshly introduced cooling water so that the rapid change in the cooling water temperature at the thermostat valve and the resulting hunting of the thermostat valve can be avoided.

Water-cooled outboard marine engine

A piston is reliably cooled from its backside by using an oil for lubricating portions around a crank pin of a crankshaft. An engine including a crankshaft is provided with lubricating oil bores to supply an oil from journals of the crankshaft to an outer peripheral surface of a crank pin. A larger end of the connecting rod is provided with a pair of opposed axial oil grooves in its outer peripheral surface, and with an annular oil passage connected to the axial groove in its side thrust face. A pair of cooling oil injection grooves each have one end connected to the annular oil passage and the other end directed to a piston while they are provided proximate to each other.

Piston oil-cooling device in an engine

In an outboard motor including a centrifugal clutch system between the engine crankshaft and the drive shaft and including an exhaust pipe that has an outlet which is submerged under water in an operable state of the outboard motor, the exhaust pipe is provided with an exhaust vent which is positioned above water in an operable state of the outboard motor. Thus, when a reverse rotation takes place in the event of unsuccessful engine start, the exhaust vent allows atmospheric air to flow into the exhaust pipe so as to prevent the internal combustion engine from working as a suction pump and introducing water into the engine cylinder through the exhaust pipe.

Outboard Motor

In an outboard marine drive, the engine is received in an under case, and is closed by both a fan cover and an engine cover so that the engine may be entirely covered by the engine cover jointly with the under case for a favorable aesthetic effect. However, the fan cover covers the engine closely in cooperation with the under case so that a narrow air passage is defined around the engine, and cooling air of high velocity can be continuously passed around the engine. Thus, according to the present invention, no part of the engine is exposed, but the fan cover surrounding the engine defines an appropriate gap around the engine for effectively guiding cooling air around the engine.

Outboard marine drive powered by an air-cooled internal combustion engine

In an outboard marine drive, a tubular socket member is sealingly fitted into an opening formed on one side of the crankcase of the engine at a level corresponding to a normal engine lubricating oil level, and a transparent window member is sealingly fitted into an outer end of the tubular socket member. An engine cover covering the engine is provided with an opening aligned with the transparent window member so as to allow the level of lubricating oil in the crankcase to be inspected from outside the engine cover. The socket member may also be provided with an oil filler pipe bifurcating upwardly from the socket member at an oblique angle, and an oil drain pipe bifurcating downwardly from the socket member at an oblique angle so that filling and removing lubricating oil into and out of the crankcase of the engine can be easily accomplished without complicating the structure for managing engine lubricating oil.

Lubricating oil managing arrangement for an outboard marine drive engine

In an outboard marine drive including a vertically oriented engine, a disk member is attached to a lower end of the crankshaft of the engine, and the upper end of the drive shaft is disposed coaxially with respect to the crankshaft and at a prescribed distance from the disk member so that a direct coupling member and an centrifugal clutch device may be interchangeably installed between them. The disk member is provided with axial holes for either pivotally supporting clutch shoes or fixedly attaching the upper end of the direct coupling member. The lower end of the direct coupling member and the clutch drum of the centrifugal clutch device are provided with an identical coupling arrangement for coupling with an upper end of the drive shaft.

Power transmission arrangement for an outboard marine drive

In an outboard marine drive, a primary partition made of elastomeric material is provided in a lower part of the extension case, and a drive shaft and an exhaust pipe are sealingly passed through the primary partition. Thereby, the extension case is kept out of direct contact from the exhaust gas, and is therefore prevented from excessive heating. The exhaust pipe and the drive shaft typically have a large length, and it is advantageous to support them at parts thereof near a lower end thereof. The use of elastomeric material for the primary partition is particularly advantageous because it not only can favorably insulate heat but also can accommodate any positional errors in the exhaust pipe and the drive shaft relative to the extension case. When a secondary opening is formed in an upper part of the exhaust pipe to prevent excessive build up of exhaust back pressure when the engine is idling, a secondary partition may also be provided in an upper part of the extension case.

Exhaust arrangement for an outboard marine drive engine

In a fuel supply system for a multi-cylinder engine, a pump driving cam is provided between an intake cam and an exhaust cam on a camshaft. The pump driving cam and a fuel pump are interconnected by a pump driving member. The pump driving member is slidably supported on a pair of supporting portions which are projectingly, integrally provided on a cylinder head and disposed between valve springs of a pair of intake valves. Thus, the intake valves and the valve springs are prevented from interfering with the pump driving member and the supporting portions and therefore, the fuel pump driven by the camshaft in the multi-cylinder engine can be disposed at a lengthwise intermediate portion of the camshaft. As a result, the distance between the fuel pump and each of the carburetors can be decreased to enable a stable supply of fuel.

Fuel supply system for multi-cylinder engine

A partially heat denatured yolk prepared by heating a yolk fluid at the temperature from 65.degree. C. to 70.degree. C. and maintaining the said temperature for 5 minutes or more, which can improve the flavour, features and functions of yolk. The said partially heat denatured yolk can be prepared by heating by applying an electric current to the yolk. Further, an emulsion prepared by processing 30-95 weight parts of the partially heat denatured yolk together with 5-70 weight parts of oils and fats to obtain an O/W type emulsion can be used as an emulsifier. The emulsifying ability of said emulsifier can be improved by adding vinegar or acetic acid and/or salt.

Partially denatured yolk obtained by heating the yolk and an emulsifier

A disclosed engine assembly comprises an engine; a crank shaft having an end extending outward from inside the engine; a rotating body mounted at the end of the crank shaft; a cover body mounted on the engine so as to cover the rotating body; the cover body comprising a lower cover that covers at least lower part of the rotating body and an upper cover connected to the lower cover so as to cover at least upper part of the rotating body; the lower cover having at least one ventilating intake port for sucking hot air located around the engine under the intake port; the upper cover having a ventilating exhaust duct for discharging the sucked hot air; the rotating body including a timing belt located near one side of the engine, a tensioner located near one side of the engine and having a mounting position adjustment bolt for adjusting a tension on the timing belt, and a manually starting pulley located on one side of the engine outside the timing belt; and the starting pulley having at least one opening located so as to engage with the amounting position adjustment bolt of the tensioner. This constitution enables hot air existing around the engine under the lower cover to be discharged smoothly to the outside of the engine cover via the cover body, thereby preventing hot air from being stranded under the lower cover. In addition, the position of the mounting position adjustment bolt can be perceived easily by simply aligning the opening with the bolt.

Engine assembly

A camshaft includes a first end journal portion and first, second and third intermediate journal portions respectively. The first end journal portion is supported in a bearing hole in an upper end wall of the cylinder head. The first, second and third intermediate journal portions are supported in three bearing holes in the three intermediate bearing bosses in the cylinder head, respectively. The radii of the four bearing holes and of a camshaft inserting opening in a lower end wall of the cylinder head are in a relationship such that the camshaft inserting opening is the largest radii, and each adjacent bearing hole is progressively smaller in size. The smallest radii bearing hole is for the bearing hole for the first end journal portion. The largest radius of an intake cam and an exhaust cam is smaller than the radii of the intermediate bearing holes. Thus, the camshaft can be smoothly inserted through the camshaft inserting opening and hence, can be easily assembled into the cylinder head.

Camshaft supporting structure in an engine

A joint structure joins an outboard engine assembly to a boat hull. The outboard engine assembly has an engine, a case, a propeller rotatably supported on the case and drivable by the engine. The joint structure includes an attachment adapted to be coupled to the boat hull, the case having an inner surface defining an inner housing region, and elastic mount mechanism accommodated in the inner housing region for elastically supporting the case to the attachment. The elastic mount mechanism comprises a support member coupled to the attachment, and an elastic member disposed on the support member, the elastic member being elastically deformable from partial abutment to full abutment against a portion of the inner surface of the case in response to an increase in compressive forces which are applied between the case and the attachment when the engine is in operation. For example, the portion of the inner surface may include a flat inner surface substantially normal to the direction in which the compressive forces are applied, the elastic member having an outer surface facing the flat inner surface and having a plurality of protrusions which are elastically deformable from partial abutment to full abutment against the flat inner surface when the compressive forces are increased.

Growing community of inventors

Wako, Japan

Mitsuharu Tanaka