Koki Holdings Co., Ltd.

Hitachi Koki Co., Ltd.

Junichi Toukairin

Shota Takeuchi

Takuhiro Murakami

Tomomasa Nishikawa

Hiroyuki Hanawa

Takuya Teranishi

Kengo Tamura

Nobuhiro Takano

Kazuhiko Funabashi

Akira Matsushita

Shinji Watanabe

Toshio Mizoguchi

Yasushi Nakano

Yoshihiro Komuro

Masayuki Ogura

Shota Kanno

Yusuke Funabiki

Masaru Hirano

Junpei Sato

Hikaru Tamura

Takashi Ueda

Shinki Ohtsu

Katsuhiro Oomori

Hideki Watanabe

Takuma Saito

Hayato Yamaguchi

Osamu Kawanobe

Naoto Wakatabe

Masanori Okada

Takeshi Taniguchi

Kazutaka Iwata

Yoshiki Aoki

Haruhisa Fujisawa

Shinichi Kakefuda

Takao Aradachi

Hiroki Uchida

Takashi Takeda

Naoki Tadokoro

Hironori Mashiko

Yuji Kishima

Yuta Noguchi

Yutaka Ito

Keita Saitou

Jyun Enta

Itsushi Ogawa

Yasuoki Kawahata

In a working device, a cover added outside an enclosure portion is used to utilize vibration of the working device during an operation thereof to cool the enclosure portion. The working device has: a motor; a speed reduction mechanism for decelerating rotation of the motor; a striking mechanism; an enclosure portion (main body housing, hammer case) accommodating them; and a cover covering at least a portion of an outer surface of the enclosure portion. An airflow passage is formed between an outer surface of the hammer case and the cover and is configured so as to allow inflow and outflow of outside air. The cover is held so as to be slightly movable by sandwiching an elastic member in an axial line direction and, by the cover being moving forward and backward during its operation, air goes into or comes out of the airflow passage to cool the hammer case.

Working device

An impact tool includes a hammer that is rotated by a motor and energized toward a front side from a spindle by a cam mechanism and a spring, and an anvil that is struck by the hammer. The hammer includes a main body part, and claw parts extending forward from the main body part, and tapered surfaces are formed such that an inner diameter side end of each of the claw parts of the main body part is located on the front side relative to an outer diameter side end of the claw part. The tapered surfaces are formed, on an outer peripheral side of a front facing surface of the hammer, in such a shape that the tapered surfaces recede as separating in a radial direction from a rotation axis.

Impact tool

An electric tool to restrain stress concentration is provided. The electric tool includes a housing (), a motor (), an anvil (), and an impact mechanism (). The motor is accommodated in the housing and rotatable. The anvil supported by the housing and rotatable about an axis (A). The impact mechanism is configured to convert a rotational force generated by the motor into a rotational impact force about the axis, and to apply the rotational impact force to the anvil. The anvil includes a base portion (), an end bit attachment portion (), and a connecting portion (). The base portion is rotatably supported by the housing. An end bit is attachable to the end bit attachment portion. The end bit attachment portion has a flat surface portion. The connecting portion integrally connects together the base portion and the end bit attachment portion. The connecting portion has a diameter gradually reduced in a direction from the base portion toward the end bit attachment portion. The connecting portion is formed with a recessed portion (A,B,). The connecting portion has an outer peripheral surface portion where the recessed portion is formed. The recessed portion is recessed, in an axial direction from the end bit attachment portion toward the base portion, from a point where the recessed portion is connected to the outer peripheral surface portion in a cross-section taken along a plane parallel to the flat surface portion and passing through the recessed portion.

Power tool

Provided is a rotary tool with a compact tip tool holding portion (). The rotary tool is provided with a sleeve () attached to an output shaft () to switch a tip tool () between a fixed state and a detachable state. The output shaft () has a through hole () formed therein radially penetrating from the inside to the outside of a mounting hole thereof. The through hole () has a steel ball () provided therein such that at least a part of the steel ball () overlaps at least a part of a case (). The sleeve () defines a first position in the outward direction of the steel ball (), while the case () regulates a second position on the radially outer side of the first position.

Rotary tool

The electrical apparatus, in which a series connection state and a parallel connection state of an upper cell unit including five battery cells and a lower cell unit can be automatically switched by means of a difference in a terminal shape on the electrical apparatus body side, has a terminal holder and holds apparatus side terminals. The terminal holder, which establishes an electrically connected state with the connection terminals of the battery pack, is provided with two parallel protruding parts that extend in the forward-backward direction, and second rail grooves fitted to the protruding parts on the electrical apparatus side. Due to the fitting, relative movement of the terminal holder and the battery pack in the vertical direction can be suppressed, and wear on the apparatus side terminals can be greatly suppressed.

Electrical apparatus using battery pack

A battery pack houses first and second cell units that are composed of a plurality of cells, and has a positive electrode power source terminal and a negative electrode power source terminal. This battery pack is provided with a series connector capable of connecting, in series, the first and second cell units and a parallel connector capable of connecting, in parallel, the first and second cell units, and is capable of switching between a parallel connection voltage and a series connection voltage. In the case of attachment to the high voltage electrical device body, the series connector becomes conductive and the parallel connector pair is cut off by the action of the series/parallel switching terminal. In the case of attachment to a low voltage electrical device body, the state is returned to an initial state, the series connector is cut off, and the parallel connector pair becomes conductive.

Battery pack, electrical device using battery pack, and electrical device system

Provided is an electric device capable of suppressing vibration of a battery pack. Included are: a first housingaccommodating a load portion that consumes electric power; a second housinghaving one end portion connected to the first housingand another end portion to which a battery packis connectable; and an elastic memberinterposed between the first housing and the second housing. The first housing includes a first restricting portionpositioned away from the elastic member, and the second housing includes a second restricting portionpositioned away from the elastic member and engageable with the first restricting portion. In a case where the second housing is urged to be separated from the first housing, the elastic member is deformed and the first restricting portion and the second restricting portion are engaged with each other to prevent separation.

Electric device

In an upper cell unit () and a lower cell unit () comprising five battery cells, positive electrode terminals () are set apart and aligned vertically, and negative electrode terminals () are set apart and aligned vertically. When an electrical device body is rated at 36V, device-side terminals are in contact only at the upper terminals (), and short circuiting of the lower terminals () is effected using a short bar. When the electrical device body is rated at 18V, the upper and lower terminals (andand) are simultaneously made to contact the device-side terminals, and the upper cell unit () and the lower cell unit () assume a parallel connected state. Thus, it is possible to automatically switch the output voltage when a battery pack is mounted according to the difference in terminal shape on the electrical device body side.

In order to provide an impact work machine capable of preventing oil leakage and cooling a power transmission apparatus, an impact work machine transmitting power of an electric motorincluding an output shaft extending in an axis Adirection to an anvil includes: a housing including a motor case accommodating the electric motor, and a grip extending from the motor case; a speed reducer and an impact mechanismeach transmitting power of the electric motor to the anvil; a hammer case located forward of the motor case and nonrotatable relative to the motor case; an extension portion provided on the housing and extending from the motor case toward the hammer case so as to cover at least part of the hammer case; and a passage provided between the hammer case and the extension portion and through which air passes.

Work machine

In order to provide an impact tool which is capable of increasing a striking force in a rotational direction of being applied from a hammer to an anvil, the impact tool includes: an electric motor; an anvil which supports a work tool and is driven by the electric motor; and a hammer which applies the striking force in the rotational direction to the anvil. The impact tool is provided with: a spindle which is arranged to be concentric with the anvil, supports the hammer to be movable in an axial direction and the rotational direction with respect to the anvil, and transmits motive power of the electric motor to the anvil; and a control unit which controls rotation speed of the electric motor. The number of strokes of the anvil due to one rotation of the hammer differs in response to rotation speed of the electric motor.

A powered working machine facilitating work of fixing a tip tool to a tool supporting member is provided. A powered working machine in which a tip tool is driven by power of an electric-powered motor includes: an output shaft to which the tip tool is attached; a tool fixing member which fixes the tip tool to the output shaft; a second shaft to/from which the tool fixing member is attached/detached; a clamp having a locked state in which a state of attachment of the tool fixing member to the second shaft is maintained and an unlocked state in which the tool fixing member can be detached from the second shaft; and a guide member having a first rotation position at which the clamp is in the locked state and a second rotation position at which the clamp is in the unlocked state.

Powered working machine

According to an aspect of the present invention, there is provided a power tool including: a brushless motor; switching elements that drive the brushless motor; a circuit board on which the switching elements are mounted; a transmission portion that transmits a driving force of the brushless motor; and a housing that houses the brushless motor, the switching elements, the circuit board and the transmission portion therein, wherein the switching elements include semiconductor elements each having terminals on a bottom surface thereof, and wherein the switching elements are surface mounted on the circuit board.

A battery pack for use with a battery-driven power tool includes three battery cells in which two out of three are arranged horizontally in parallel to and in alignment with each other in a lower case and the remaining one battery cell is vertically arranged in an upper case. The upper case of the battery pack is inserted, in use, into a battery pack receiving space formed in the grip portion of a power tool. Therefore, the grip portion can be made thin and usability of the power tool is enhanced.

Battery pack and battery-driven power tool using the same

An electric power tool () includes a brushless direct-current motor () and a drive circuit that supplies drive power to the motor, the power tool rotates or drives a tool, whereby the drive circuit includes plural switching elements (), and is arranged on a board () provided in a grip portion of a housing or below the grip portion; and an electric fan () is provided in the vicinity of the switching element for cooling the switching element.

Electric power tool

An electric power tool includes: a motor including a motor shaft; a tip tool driven by the motor; a housing that houses the motor; a switching element for driving the motor; and a bearing that can retain the motor shaft. The switching element is provided so as to overlap with the bearing in a direction of the motor shaft inside the housing.

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Ibaraki, Japan

Junichi Toukairin