Abstract: A multipurpose engine has a wiring structure between the generator and electrical components. A connector box is provided in a gap defined directly between the generator and the fuel tank. A plurality of electrical wirings is interconnected inside the connector box.

Abstract: An oil level detection apparatus having a float-type oil level detector (50) and a mode switching unit. The oil level detector emits a signal indicating that the oil level has dropped when a movable contact disposed on a float (54) makes contact with fixed contacts once the level of oil (Lu) has dropped to a lower limit level. The mode switching unit switches between one of two modes selected from a first mode for actuating the alarm and stopping the engine (10) in accordance with the level drop signal, and a second mode for actuating the alarm and continuing to operate the engine (10) in accordance with the level drop signal.

Abstract: An air-cooled engine (10) is cooled by cooling air (Wi). The air-cooled engine (10) includes a cylinder block (33) and a cylinder head (28). The cylinder block (33) has cylinder cooling through-ducts (101, 102) capable of transmitting cooling air (Wi), on the periphery of a cylinder (26). The cylinder head (28) has a head-cooling through-duct (104) capable of transmitting cooling air (Wi). The cylinder-cooling ducts (101, 102) and the head-cooling duct (104) extend in a direction perpendicular to the axial line (109) of the cylinder (26), and are communicated with each other by means of communication channels (105, 105).

Abstract: An air-cooled engine (10) has a fan cover (16) for covering a cooling fan (14). The cover (16) is composed of a fan-cover peripheral wall (44) for covering the outside of the cooling fan (14), and a top board (45) for closing off one end of the fan-cover peripheral wall (44). The fan-cover peripheral wall (44) has an internally disposed guiding duct (47) for guiding cooling air (Wi) from the cooling fan (14) to an engine main body (12). A first fastening member (42) secures a portion of the external part of the fan-cover peripheral wall (44) that is proximal to the guiding duct (47) to a casing (25) of the engine main body (12). A second fastening member (41) extends from the casing (25) and through the fan-cover peripheral wall (44), and secures a top board (45) in a portion that is at a distance from the guiding duct (47).

Abstract: An oil level detection apparatus having a float-type oil level detector (50) and a mode switching unit. The oil level detector emits a signal indicating that the oil level has dropped when a movable contact disposed on a float (54) makes contact with fixed contacts once the level of said oil (Lu) has dropped to a lower limit level. The mode switching unit switches between one of two modes selected from a first mode for actuating the alarm and stopping the engine (10) in accordance with the level drop signal, and a second mode for actuating the alarm and continuing to operate the engine (10) in accordance with the level drop signal.

Abstract: An air-cooled engine (10) is cooled by cooling air (Wi). The air-cooled engine (10) includes a cylinder block (33) and a cylinder head (28). The cylinder block (33) has cylinder cooling through-ducts (101, 102) capable of transmitting cooling air (Wi), on the periphery of a cylinder (26). The cylinder head (28) has a head-cooling through-duct (104) capable of transmitting cooling air (Wi). The cylinder-cooling ducts (101, 102) and the head-cooling duct (104) extend in a direction perpendicular to the axial line (109) of the cylinder (26), and are communicated with each other by means of communication channels (105, 105).

Abstract: A multipurpose engine having an improved wiring structure between the generator (46) and electrical components is disclosed. A connector box (104) is provided to the dead space formed between the engine main body (27) and the fuel tank (37). A plurality of electrical wirings (151 to 156) is interconnected inside the connector box.

Abstract: An air-cooled engine (10) has a fan cover (16) for covering a cooling fan (14). The cover (16) is composed of a fan-cover peripheral wall (44) for covering the outside of the cooling fan (14), and a top board (45) for closing off one end of the fan-cover peripheral wall (44). The fan-cover peripheral wall (44) has an internally disposed guiding duct (47) for guiding cooling air (Wi) from the cooling fan (14) to an engine main body (12). A first fastening member (42) secures a portion of the external part of the fan-cover peripheral wall (44) that is proximal to the guiding duct (47) to a casing (25) of the engine main body (12). A second fastening member (41) extends from the casing (25) and through the fan-cover peripheral wall (44), and secures a top board (45) in a portion that is at a distance from the guiding duct (47).

Abstract: An inspection method is conducted after the assembly of an industrial engine is complete. An identification code assigned to an industrial engine is read. Basic engine specification data and device-specific engine specification data that correspond to the read identification code are extracted from a database to a completion inspection unit. Various inspections are conducted on the individual engine by the completion inspection unit on the basis of the extracted basic engine specification data. The device-specific engine specification data of the engine that has passed the inspection is written into memory. A confirmation inspection is then conducted by a device-specific inspection machine to determine whether the engine has the output characteristics required by the mounting device.

Abstract: An inspection method is conducted after the assembly of an industrial engine is complete. An identification code assigned to an industrial engine is read. Basic engine specification data and device-specific engine specification data that correspond to the read identification code are extracted from a database to a completion inspection unit. Various inspections are conducted on the individual engine by the completion inspection unit on the basis of the extracted basic engine specification data. The device-specific engine specification data of the engine that has passed the inspection is written into memory. A confirmation inspection is then conducted by a device-specific inspection machine to determine whether the engine has the output characteristics required by the mounting device.

Abstract: A valve-operating device for an engine includes a camshaft which is disposed on one side of a plane including axes of an exhaust valve and an intake valve and which has an axis substantially perpendicular to the plane. The camshaft and the exhaust and intake valves are connected to each other through a first rocker arm and a second rocker arm which are swingably carried on a rocker shaft disposed substantially perpendicular to the plane. The camshaft is formed with a large-diameter exhaust cam and a small-diameter intake cam adjoining a portion of the exhaust cam on the side of the plane. The exhaust and intake rocker arms are provided with arm portions extending in an axial direction of the camshaft to come into sliding contact with outer peripheral surfaces of the exhaust and intake cams, respectively. Thus, it is possible to open and close the exhaust and intake valves with inherent opening and closing timings, while easily avoiding interferences among components.

Abstract: A variable compression ratio engine includes a support shaft positioned eccentrically relative to rotating shafts. A restricting projection is provided at one location in the circumferential direction on the rotating shafts so as to project outward in the radial direction. A rocker member has a pair of engagement portions with respective phases displaced from each other and which engage the restricting projection. The rocker member is spring-biased in a direction in which one of the two engagement portions engages the restricting projection and is mounted on a shaft member so as to be able to rock around the axis of the shaft member. An actuator is driven by the engine negative pressure and is connected to the rocker member so as to swing the rocker member in a direction opposite to the spring-bias direction.

Abstract: 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.

Abstract: A variable compression ratio engine includes a support shaft positioned eccentrically relative to rotating shafts. A restricting projection is provided at one location in the circumferential direction on the rotating shafts so as to project outward in the radial direction. A rocker member has a pair of engagement portions with respective phases displaced from each other and which engage the restricting projection. The rocker member is spring-biased in a direction in which one of the two engagement portions engages the restricting projection and is mounted on a shaft member so as to be able to rock around the axis of the shaft member. An actuator is driven by the engine negative pressure and is connected to the rocker member so as to swing the rocker member in a direction opposite to the spring-bias direction.

Abstract: A valve-operating device for an engine includes a camshaft which is disposed on one side of a plane including axes of an exhaust valve and an intake valve and which has an axis substantially perpendicular to the plane. The camshaft and the exhaust and intake valves are connected to each other through a first rocker arm and a second rocker arm which are swingably carried on a rocker shaft disposed substantially perpendicular to the plane. The camshaft is formed with a large-diameter exhaust cam and a small-diameter intake cam adjoining a portion of the exhaust cam on the side of the plane. The exhaust and intake rocker arms are provided with arm portions extending in an axial direction of the camshaft to come into sliding contact with outer peripheral surfaces of the exhaust and intake cams, respectively. Thus, it is possible to open and close the exhaust and intake valves with inherent opening and closing timings, while easily avoiding interferences among components.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An OHC vertical crankshaft engine, comprising: a vertically disposed crankshaft having a first timing pulley at its lower end; a cooling fan attached to an upper end of the crankshaft; a camshaft extending in parallel with the crankshaft at a cylinder head end of the engine and having a second timing pulley at its lower end; and a timing belt passed around the timing pulleys. Thus, the need for lubrication for the transmission mechanism between the crankshaft and the camshaft is substantially eliminated, and the noise generation is reduced. Additionally, since the upper part of the cylinder head is directly exposed to the cooling air produced by a fan provided at an upper end of the crankshaft, a high engine cooling efficiency can be achieved. This effect is even more enhanced if the exhaust port of the engine is disposed above the intake port and extends horizontally and linearly away from the engine.

Abstract: A liquid cooled internal combustion engine, comprising: an integrally cast engine main body including a cylinder block, a cylinder head, and a crankcase skirt, a crankcase cover attached to an open end of the skirt to define a crankcase therein, a crankshaft extending vertically in the crankcase and rotatably supported by the skirt at its both ends, a camshaft rotatably supported by the cylinder head and extending in parallel with the crankshaft, a timing belt passed around pulleys mounted on lower ends of the camshaft and the crankshaft, respectively, and extending in a belt chamber defined in the cylinder block along a lower side of the cylinder bore; a cooling liquid jacket defined in the cylinder block along upper and lateral sides of the cylinder bore. The jacket may be formed during the casting process by pulling a core either upwards or toward the open end of the skirt. The cooling liquid may consist of the lubricating oil for the engine.