Ryobi North America, Inc.

Ryobi Limited

Ryobi Outdoor Products, Inc.

Mtd Southwest, Inc.

Ryobi America Corp.

Harry Gene Rickard

Robert G Everts

Kenneth M Brazell

Harold J Coleman

Kouichi Miyamoto

Tatsuya Wada

Mitsumasa Sato

Takeshi Shiotani

Shiro Kawamoto

Yoichi Imgawa

John Sheldon

Katsutoshi Kouichiyama

A portable, operator-carried power tool having an implement supported on frame, and a lightweight, four-stroke, engine drivably connected to the implement. The engine has a crankshaft situated in a crankshaft housing and a cylinder block secured to the 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, cam region and valve chamber form a containment whereby oil mist is distributed throughout the engine during operation regardless of angular orientation.

Multiple-position, operator-carried, four-stroke engine

Line feed mechanism for a line trimmer

A compression release mechanism for a combustion chamber in an internal combustion engine comprises a pressure relief valve assembly and a control member. The valve assembly includes a valve body and a plunger cooperating with a vent passageway through the valve body to selectively allow pressure relief through the vent passageway. The control member cooperates with the plunger and is movable between an engaged position in which the control member urges the plunger toward the open position, and a disengaged position in which the plunger is held in the closed position. When the control member is engaged, the plunger oscillates between the open and closed positions in response to combustion chamber pressures during a combustion cycle which facilitates engine start-up while the compression release mechanism is engaged.

Compression release mechanism for an internal combustion engine

A line trimmer head is provided including a rotatable drive shaft and a housing mounted to the drive shaft for rotation therewith. The housing has an open end and at least one peripheral aperture formed through the housing. A spool subassembly is positioned at least partially within the housing adjacent the open end of the housing. The subassembly includes a spool having at least one flange extending radially outwardly from the periphery thereof, a cog ring secured to the spool, and a ratchet and pawl assembly formed between the cog ring and spool. The ratchet and pawl assembly allows rotation of the spool in a first direction with respect to the cog ring for winding line around the spool while preventing spool rotation in a second direction opposite the first direction to facilitate line feed bumping and line trimming operations. In an alternative embodiment, the pawl is integrally molded with the spool to eliminate the separate spring-pawl assembly.

Line feed configuration for line trimmers

A split-boom power tool includes a housing adapted to carry a battery or motor. A first boom member connected to the housing includes an electromechanical or mechanical joint (i.e., coupling) connected thereto for receiving a second boom member, which carries an attachment. The attachment may include a hedge trimmer, line trimmer, pruner, blower, or extension. Various couplings or mechanical joints are provided.

Coupling for split-boom power tool

A line trimmer head is provided including a rotatable drive shaft and a housing mounted to the drive shaft for rotation therewith. The housing has an open end and at least one peripheral aperture formed through the housing. A spool subassembly is positioned at least partially within the housing adjacent the open end of the housing. The subassembly includes a spool having at least one flange extending radially outwardly from the periphery thereof, a cog ring secured to the spool, and a ratchet and pawl assembly formed between the cog ring and spool. The ratchet and pawl assembly allows rotation of the spool in a first direction with respect to the cog ring for winding line around the spool while preventing spool rotation in a second direction opposite the first direction to facilitate line feed bumping and line trimming operations.

A drill press assembly having a base mountable to a work bench, a vertical column attached to the base and a drill head assembly having an electric motor and a quill. The drill head assembly is movably attached to the column. A rack is rotatably attached to the top of the column and is engaged by a crank and pinion mechanism attached to the frame of the drill head assembly which permits the drill head assembly to be displaced vertically and rotated about the column. A tilt table is attachable to the base of the drill press. A locking mechanism having a bolt passing through a longitudinal slot in the supporting base of the tilt table and a transverse slot in the base is engaged by an eccentrically mounted camshaft to lock the supporting base of the tilt table to the top surface of the drill press base. A pivoting frame is pivotably attached to the supporting base and contains a table plate. A fence is attachable to the top of the pivoting frame. The fence has a stopping block to facilitate the location of a workpiece on the tilt table. A work clamp is also provided on the drill head assembly to clamp a workpiece on the tilt table.

Drill press having a movable head and a tilt table

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.

Laminated gear and method of forming a laminated gear

A collapsible stand having a top (14) formed by two mating leaves (15, 17) and supported by legs (28, 30, 32, 34). The legs are pivotedly joined to braces (20, 22, 24, 26) underlying the leaves. The components of the stand pivot with respect to one another so to allow the stand to be easily erected and collapsed. However, due to interaction between at least one of the braces and at least one retainer (64) on the underside of one of the leaves the stand cannot be collapsed without initial planar movement of the leaves away from one another. Since such movement is rare during normal usage, the stand is strong and secure during normal usage. A pair of brackets (80, 82) for holding dimensional lumber (79) may be attached to the braces. When the lumber is placed in the brackets, the stand is further secured in its erect position.

Growing community of inventors

Phoenix, AZ, United States of America

Harry Gene Rickard