Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Akira Onose

Hiroki Uchida

Masato Sakai

Takeshi Taniguchi

Kenichirou Yoshida

Shinji Kuragano

Kihachirou Matsumoto

Tomomasa Nishikawa

Hiroshi Sato

Shinki Ohtsu

Shinichi Kakefuda

Eiji Nakayama

Hitoshi Tsuzuki

Shinji Takano

Takashi Ozawa

Takuya Konnai

Takeru Kumakura

Toshiaki Takagi

Naoya Etou

Kihachiro Matsumoto

Shinichi Sakuma

Satoshi Hotta

Ryoji Tuchida

Naoto Yamashiro

There is provided an electric power tool having a plurality of operation modes with different rotation speeds at least in a predetermined load range. The electric power tool is capable of switching between the operation modes when a predetermined condition is satisfied even during a motor is driven, and configured such that a rotation speed of the motor is changed smoothly or in a stepwise manner at the switching between the operation modes.

Electric power tool

An electric power tool includes a brushless motor, a control unit configured to control power supply to the brushless motor, a rotary tool configured to be rotated by the brushless motor, a rotation speed detecting unit configured to detect a rotation speed of the brushless motor, a main switch configured to transmit, to the control unit, an ON/OFF signal for switching between driving and stopping of the brushless motor, and a mode switching unit configured to transmit, to the control unit, a mode switching signal for switching between multiple modes of rotation control of the brushless motor, the control unit is configured to perform the rotation control of the brushless motor in any one of the multiple modes including at least a high-speed mode and a low-speed mode.

A power planer includes a casing, a motor having rotation shaft, a power supply portion for supplying electric power to the motor, a control portion, a cutter block, and a fan. The casing has intake and discharge openings and provides an air passage from the intake opening to the discharge opening. The control portion is connected to the electric motor and to the power supply portion. The cutter block has an axis parallel to the rotation shaft, and is supported to the casing and rotatable about the axis. A blade is provided in the cutter block. The fan is provided in the casing and configured to generate air stream within the casing and flowing along the air passage in a flowing direction. The air passage includes a control portion cooling passage for cooling the latter. The fan is positioned downstream of the control portion in the flowing direction.

Power planer configured to restrain heat generation of control portion

The portable belt grindercomprises; a main bodywith an electric motorbuilt therein; a drive pulley disposed in the lower portion of the main bodyand rotationally drivable by the electric motor; an idle pulley disposed as the companion to the drive pulley; and, an endless abrasive beltwound between the two pulleys. In the portable belt grinder, in the portion of the main bodythat exists in the vicinity of the abrasive belt, there is formed a hole portionwhich is used to visually confirm the side end edge of the abrasive beltfrom above. Also, on the upper surface of the main body, there is mounted a transparent coverwhich is used to cover the hole portion

Portable belt grinder

A portable electric power tool including a housing having one end to which an L-shaped battery pack is installable. A motor is accommodated in the housing. A switch assembly includes a switch body installed in the housing. The switch body is overlapped with the L-shaped battery pack in a longitudinal direction of the power tool. The switch assembly further includes a trigger including a pivot portion, a manipulation portion extending frontward from the pivot portion and pivotally movable, and a lever portion extending rearward from the pivot portion to actuate the switch body. The manipulation portion is disposed to overlap with a center of gravity of an entire power tool in the longitudinal direction, and the pivot portion is positioned between the manipulation portion and the switch body.

Portable electrical power tool

A portable belt sander having a drive pulley capable of being produced at a limited period. The sander includes a main body accommodating therein a motor, a drive shaft rotationally driven by the motor, a drive pulley coupled to the drive shaft, a driven shaft, and an endless polishing belt mounted between the drive pulley and the driven pulley. The drive pulley includes a base section coupling the drive shaft and made from a rigid material, and an outer low hardness section made from an elastomer material and disposed over an outer peripheral surface of the base section and integrally therewith by injection molding. Mating surfaces between the base section and the outer section are irregularly formed.

Portable belt sander

A power tool including: a base slidable on a workpiece, and an opening provided through the base; a main unit supported to the base and movable in a first direction substantially perpendicular to the base, the main unit including an electric motor; a cutter driven by the electric motor, the cutter being capable of protruding through the opening from the base; a stopper pole supported to a housing coupled to the main unit, the stopper pole being movable in the first direction, the stopper pole having one end protruding from the housing toward the base, thereby regulating a moving distance of the cutter; a digital display unit including a moving distance detection portion for detecting a moving distance of the stopper pole and a digital display portion for displaying the moving distance; and a dust prevention member provided between a part of the stopper pole protruding toward the base and the moving distance detection portion, thereby preventing dust from entering into the housing.

Power tool

Portable electric driver

A power tool has a base, a main unit, a cutter, a bolt, an engagement member, and a unit. The base has a sliding surface slidable on a workpiece, another surface opposite to the sliding surface, and an opening in the base. The main unit is movable in a first direction substantially perpendicular to the sliding surface. The cutter is driven by a electric motor in the main unit to protrude through the opening from the sliding surface during an operation. The bolt extends in the first direction on the first side, a first male thread, and one end supported by the base. The bolt is rotatable about the longitudinal axis. The engagement member has a first female thread threadably engaged with the male thread. The engagement member is movable between an engaged position with the boot and a disengaged position therewith. The unit maintains the engagement member at the disengaged position in a second direction. The rotation of the bolt causes the first male thread portion to thread with respect to the first male thread portion, thereby moving the main unit in the first direction and adjusting a distance of the main unit to the sliding surface.

Portable electric sander

A compact and light-weight portable electric router produced at a low cost and capable of providing high cutting efficiency with low noise. A radial fan includes a cylindrical hub functioning as an attachment portion to a motor shaft, a plurality of fan blades having parts connecting to the hub, and a ring like guide section connected to the hub through the fan blades. An annular weight is connected to the guide section at a radially outer side of the guide section. The weight serves as a restriction section for restricting backflow of air from a discharge side to a motor side.

Portable electric router having radial fan

A portable electrical tool includes a tip tool; a cylindrical housing accommodating a motor including a chuck attachably and detachably holding the tip tool at tip end of a rotation shaft; a base including a surface plate which slides on an upper surface of work material, and which allows the tip tool to protrude from the surface plate downwardly, a cylindrical portion including a cutout portion, and a lever having a cam surface, and rotatable to a fixed position and a release position. When the lever is in the fixed position, a gap at the cutout portion is narrowed to stop movement of the cylindrical housing. When the lever is in the release position, the cylindrical housing is movable by weight in the cylindrical portion. The tool includes a stopper to stop a rotation of the lever between the fixed position and the release position.

Portable electric tool

A laser emitter projects a planer light beam to form an optical guideline on a work piece extending in a cutting direction of saw blade. The laser emitter is arranged behind, in the cutting direction, a tangential line of the circumference of the saw blade at an intersection of a bottom surface of the base and the circumference at a front side of the base in the cutting direction. The laser emitter forms the optical guideline behind the intersection in the cutting direction. The laser emitter is supported in respect of the saw blade slidingly in a direction defined by a rotation axis of the saw blade. The saw cover may have a window to transmit the laser beam toward the cutting point. A shutter selectively shutting the window may be provided.

Portable circular power saw with optical alignment

Portable electric router

A portable circular saw includes a base. A saw blade has a portion projecting downward from the base. A saw-blade cover conceals at least a part of the saw blade. A projection provided on the saw-blade cover protrudes in a direction away from the saw blade. The projection has a lower surface extending across a first plane which is parallel to an axis of rotation of the saw blade, and which contains a tangent to an outer circumference of the saw-blade at a point of intersection with a second plane including a lower surface of the base. Chips fly from the point of intersection along a direction in the first plane. The lower surface of the projection inclines relative to a line perpendicular to the tangent so as to change a path of a portion of flow of the chips toward a forward side as viewed in a cutting direction.

Growing community of inventors

Hitachinaka, Japan

Akira Onose