Abstract: A portable, operator-carried power tool having an implement supported on an operator-carried frame, and a lightweight, four-stroke, internal combustion engine drivably connected to the implement and supported by the frame. The engine has a crankshaft situated in a crankshaft housing and a cylinder block secured to the crankshaft housing, the crankshaft being provided with a crankcase ventilation passage extending between the crankcase and an outlet end in communication with an air/fuel induction passage. A passage establishes communication between the interior of the crankcase and the valve chamber through a cam and cam gear region of the cylinder block. An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, the cam region and the valve chamber form a closed oil mist containment whereby lubricating oil mist is distributed throughout the engine during operation regardless of angular orientation of the engine.

Abstract: An engine powered hand-held power tool and engine lubrication method is provided, the power tool being intended to be carried by an operator during use. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member, and a small four-cycle, lightweight, internal combustion engine attached to the frame for driving the implement. The four-cycle engine has a lightweight aluminum alloy engine block having a cylindrical bore and an enclosed oil reservoir formed therein. A crankshaft is rotatably mounted in the engine block for rotation about a crankshaft axis. A piston reciprocates within the bore and is connected to the crankshaft by a connecting rod. An oil splasher driven by the crankshaft intermittently engages the oil within the enclosed oil reservoir to splash-lubricate the engine.

Abstract: A hand held powered tool is provided which is intended to be carried by an operator during use. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member and a small four-cycle lightweight internal combustion engine attached to the frame for driving the implement. The four-cycle engine is made up of a lightweight aluminum engine block having a cylindrical bore and an oil reservoir. A crankshaft is journaled to the engine block for rotation about a crankshaft axis. A piston reciprocates within the bore and is connected to the crankshaft by a connecting rod having an oil splasher formed thereon for intermittently engaging the oil within the enclosed oil reservoir to splash lubricate the engine. The engine is provided with a cylinder head assembly defining a compact combustion chamber having a pair of overhead intake exhaust ports cooperating intake and exhaust valves.

Abstract: A portable, hand-held snow thrower comprising a power unit and an attachment removably securable to the power unit. The attachment includes an impeller having a first pulley and a flexible drive shaft. A first end of the drive shaft is connected to the power unit, and a second end of the drive shaft is drivably connected to a second pulley lying substantially in a plane with the first pulley. A lower portion of the drive shaft is curved and extends through an impeller housing. The second pulley is operably connected to the first pulley to provide a gear ratio therebetween resulting in a desired rotational speed of the impeller.

Abstract: An angle gear drive for a portable lawn care implement including first and second housing portions molded to net shape. First and second housing portions support an input shaft having a bevel gear and an output shaft having a mating bevel gear. The assembled housing portions include annular ribs for locating and restraining the input and output shafts so that the bevel gears are securely enclosed in a sealed gear cavity. The gear cavity is sealed by an anaerobic sealant. Grease is supplied to the sealed gear cavity through an axial lubrication bore formed in the input shaft along the axis of the input shaft. The method of making an angle gear drive is also disclosed.

Abstract: A motor housing for a string trimmer having a vibration damper disposed between the housing member and the motor. The motor housing has transverse motor support ribs fixedly supporting the motor. A damper chamber is formed in the housing between and end face and an adjacent transverse motor support rib. Stiffner ribs disposed between the end face and the adjacent transverse motor support rib form radial seats on diametrically opposite sides of the motor. A resilient linear vibration damper member is compressively received in each of the damper chambers between the electric motor and the radial seats.

Abstract: An angle gear drive for a portable lawn care implement including first and second housing portions molded to net shape. First and second housing portions support an input shaft having a bevel gear and an output shaft having a mating bevel gear. The assembled housing portions include annular ribs for locating and restraining the input and output shafts so that the bevel gears are securely enclosed in a sealed gear cavity. The gear cavity is sealed by an anaerobic sealant. Grease is supplied to the sealed gear cavity through an axial lubrication bore formed in the input shaft along the axis of the input shaft.

Abstract: A follower for translating rotational motion of a cam into reciprocal motion of an intake or exhaust valve is disclosed. The follower comprises a first portion adapted to be pivotably mounted on a follower shaft and a second portion adapted to contact a cam surface. The first and second portions form a generally V shape. The first portion includes a bottom and a pair of side walls connected to the bottom. Each of the side walls has a hole therethrough, and the holes are coaxially aligned to accept the follower shaft. The second portion includes a first end connected to the first portion and a second distal end which contacts the cam surface. Also disclosed is a method of making a follower from common sheet metal.

Abstract: A laminated gear and a method of forming the laminated gear are disclosed. The method comprises punching a central hole and a circular array of closely adjacent perforations in a generally planar sheet. The array defines an interior portion having the outline of the gear, and a selvedge portion disposed outboard the perforations. The central hole and the perforations are progressively stamped until they have burnished faces perpendicular to the sides of the sheet. Web portions interconnecting the interior and selvedge portions are then broken to separate the gear from the sheet. A projection and corresponding recess are then stamped on the opposite sides of the gear. A predetermined number of gears are queued and finally arranged into an assembly by frictionally nesting the projections and corresponding recesses. The central holes are thereby aligned to form a bore adapted to be press fit onto a camshaft or crankshaft. The laminated gear formed by this method is also disclosed.

Abstract: A replaceable starter assembly for a hand-held internal combustion engine of a power tool is disclosed. The replaceable starter assembly comprises a cartridge including a spool on which rope is wound and with a recoil spring for biasing the spool to rotate in one direction. The cartridge is secured to an engine housing of the power tool on the opposite side of the engine housing from the internal combustion engine. The cartridge may be detached from the engine housing of the power tool to facilitate the replacement of the starter assembly without requiring disassembly of the engine housing of the power tool. A starter housing substantially encloses the cartridge and is secured to the engine housing by removable fasteners. The starter housing may include a clutch and clutch drum which are removable with the starter housing and separable from the cartridge. The starter assembly is assembled to the power tool between the engine housing and a boom which supports the driveshaft of an implement.

Abstract: A portable hand-held blower vacuum apparatus (10) having a hinged inlet cover (24) with a handle (26) disposed at one end of the cover (24). The cover (24) is moveable between a closed position where the cover spans an air inlet opening (20) and an open position to allow insertion of a vacuum tube (50) in to the inlet opening (20). The handle (26) is used to move the cover between the open and closed positions. Air flows into the inlet opening (20) through a screen (38) in the cover (24), through arcuate slots (42) in a tubular extension (44) of the inlet opening (20) and over a circumferentially extending rib (46) formed on the cover (24). In an alternative embodiment, a dedicated blower is provided in which a solid, stationary cover (54) spans the inlet opening (20).