Patents Assigned to Hitachi Koki Co., LTD
  • Patent number: 9314908
    Abstract: According to an aspect of the present invention, there is provided an impact tool including: a motor drivable in an intermittent driving mode; a hammer connected to the motor; an anvil to be struck by the hammer to thereby rotate/strike a tip tool; and a control unit that controls a rotation of the motor by switching a driving pulse supplied to the motor in accordance with a load applied onto the tip tool.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: April 19, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Hideyuki Tanimoto, Nobuhiro Takano, Tomomasa Nishikawa, Kazutaka Iwata, Hironori Mashiko, Hayato Yamaguchi, Atsushi Nakagawa, Katsuhiro Oomori, Mizuho Nakamura, Hiroki Uchida, Saroma Nakano, Yutaka Ito
  • Patent number: 9314855
    Abstract: An electric boring tool comprises an electric motor, a switch trigger, a tip tool driven by driving force of the electric motor, a power transmission mechanism for transmitting the driving force of the electric motor to the tip tool as rotational force and/or hammer force, and a motor control unit for controlling speed of the electric motor in response to an extent of pulling of the switch trigger. The motor control unit subjects the electric motor to low speed control after the electric motor is started up, and controls the speed of the electric motor in response to the extent of pulling of the switch trigger when the load current of the electric motor is set value or greater during the low speed control.
    Type: Grant
    Filed: February 1, 2010
    Date of Patent: April 19, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Takahiro Ookubo, Kazutaka Iwata
  • Patent number: 9289832
    Abstract: An electric tool including: a motor; a housing including, a motor housing accommodating the motor, and a handle housing having one end connected to the motor housing and another other end configured to be provided with a detachable battery pack; an output part partially accommodated in the motor housing and configured to be driven by the motor; and a control board accommodated in the motor housing and configured to control the motor.
    Type: Grant
    Filed: June 15, 2012
    Date of Patent: March 22, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Yuji Kishima, Takeshi Takeda
  • Publication number: 20160052119
    Abstract: An impact tool includes a casing (13) supporting a tip tool (12), a piston (41) provided in the casing (13), an electric motor (11) provided in the casing (13), a motion converting mechanism (45) provided in the casing (13), and a vibration reducing mechanism (47) provided in the casing (13). The vibration reducing mechanism (47) has a supporting member, which is swingable with using a fixing position (J) as a supporting point and a weight (49) attached to a free end side of the supporting member. In a plane including a center line (C), the gravity center (H) of the weight (49) and the gravity center (G) of the casing (13) are disposed at mutually different locations, and the fixing position (J) is disposed on the side of the gravity center (G) relative to the center line (C).
    Type: Application
    Filed: March 19, 2013
    Publication date: February 25, 2016
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Hideki YAMADA, Takahiro OOKUBO, Satoshi ABE
  • Patent number: 9254563
    Abstract: The present invention provides a power tool that can be used at a position away from the external power source. The power tool includes a housing, a motor, an end tool, a battery pack, and an inverter. The motor is supported by the housing and driven by alternate-current power. The end tool is supported by the housing and rotatably driven by the motor. The battery pack outputs direct-current voltage. The inverter is disposed outside the housing and is configured to convert the direct-current voltage outputted from the battery pack into alternate-current voltage and supplies the motor with alternate-current power.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: February 9, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Hiroshi Yamaguchi, Toshihiko Tachibana, Yasuo Etou, Miyoji Onose, Ai Nakayama
  • Patent number: 9248517
    Abstract: A saber saw including: a motor; a housing accommodating the motor; a plunger held to be reciprocatable in the housing and to which a blade is mounted at a leading end thereof, and a movement converting part provided between the motor and the plunger and is configured to convert rotation movement of the motor into reciprocating movement of the plunger, wherein a bearing metal is fixed to an outer peripheral surface of the plunger.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: February 2, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventor: Masahiro Fujiwara
  • Patent number: 9249715
    Abstract: An air-cooled engine includes a cylinder provided with a plurality of cooling fins at an outer peripheral surface of the cylinder, a cooling fan, a cylinder cover covering the cylinder, an air guide plate, and an air guide portion. The air guide plate is positioned between an inner surface of the cylinder cover and the fins. The cooling fan generates cooling air stream for cooling the cylinder, and the air guide plate is configured to guide the cooling air stream to flow through a space between the inner surface of the cylinder cover and the fins. A first small space is defined between the air guide plate and the inner surface of the cylinder cover. The air guide portion covers at least a part of the first small space at an upstream side of the air guide plate in the axial direction of the drive shaft.
    Type: Grant
    Filed: March 3, 2014
    Date of Patent: February 2, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventor: Naoto Ichihashi
  • Patent number: 9236588
    Abstract: A battery pack includes a case having an upper case part and a lower case part. The battery pack further includes a battery cell accommodated inside the case, and a plurality of electrode terminals electrically connected to the battery cell. The upper case part has an opening which is arranged at a position corresponding to a position of the plurality of electrode terminals and exposes the plurality of electrode terminals. The batter pack additionally includes a suppressing member that suppresses foreign matter from entering inside the case via the opening.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: January 12, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Hiroyuki Hanawa, Haruhisa Fujisawa, Keita Saitou
  • Patent number: 9221162
    Abstract: The nailing machine (1) comprises an air passage (510) allowing communication between a cylinder (200) and a return air chamber (500) in which compressed air for returning a piston (300) to the initial position is accumulated. The air passage (510) is provided with a control valve (520) controlling entry of compressed air into the return air chamber (500) from the cylinder (200). The control valve (520) opens the air passage (510) and allows entry of compressed air into the return air chamber (500) in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body (100) relative to the push lever (700) is smaller than a predetermined distance. The compressed air that has entered the return air chamber (500) further enters a below-the-piston chamber and serves as air damper, reducing the driving force.
    Type: Grant
    Filed: October 13, 2009
    Date of Patent: December 29, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Hiroki Kitagawa, Masashi Nishida, Tetsuhito Shige, Kousuke Akutsu, Masaya Nagao, Shouichi Hirai
  • Patent number: 9225214
    Abstract: A disk motor including: a rotor including, a commutator disk including a commutator pattern, and at least one coil disk including a coil pattern; a stator including a magnetic flux generating part opposed to the coil pattern of the coil disk; an electric current supply part configured to supply electric current to the coil pattern via the commutator disk and, an output shaft configured to be rotated by a rotational force of the rotor, wherein a radiating pattern is provided to an outer periphery side of the commutator pattern of the commutator disk.
    Type: Grant
    Filed: August 28, 2012
    Date of Patent: December 29, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventor: Hideyuki Tanimoto
  • Publication number: 20150367490
    Abstract: A power tool, which transmits a rotational force of an intermediate shaft to a tool bit, is provided with a gear which converts the rotational force of the intermediate shaft into a striking force in a rotation direction and transmits the striking force to the tool bit, an impact sleeve, a ball, a hammer, a cylinder, a gear which does not convert the rotational force of the intermediate shaft into the striking force in the rotation direction, a sleeve, a cylinder, a motion conversion mechanism for converting the rotational force of the intermediate shaft into a striking force in a linear motion direction and transmits the striking force to the tool bit, a piston, a striker, an intermediate member, a clutch for switching the transmission paths of the rotational force of the intermediate shaft and a slide gear.
    Type: Application
    Filed: February 28, 2014
    Publication date: December 24, 2015
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Shinichirou SATOU, Yoshihiro HOSHI
  • Publication number: 20150357612
    Abstract: An electric device body in which a battery pack including a plurality of battery cells and a plurality of first terminals is detachably mounted includes: a housing; a guide mechanism; and a plurality of second terminals; and a pressed portion. The battery pack is configured to be attached to and detached from the housing along a first direction. The guide mechanism is provided at the housing and configured to define the first direction. The plurality of second terminals is configured to be connected to the plurality of first terminals upon attachment of the battery pack to the housing. The pressed portion is configured to be pressed against the battery pack in a second direction intersecting the first direction when the battery pack has been attached to the housing.
    Type: Application
    Filed: January 14, 2014
    Publication date: December 10, 2015
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Hiroki Uchida, Yoshihiro Nakano, Tetsuhiro Harada, Hideyuki Tanimoto
  • Publication number: 20150352706
    Abstract: A portable work tool includes: a housing; and a motor; and a restraining surface. The housing has an outer surface including a covered region that is covered with a soft layer and an uncovered region that is exposed to an outside. The covered region and the uncovered region define a boundary therebetween. The motor is accommodated in the housing. The restraining surface is disposed in proximity to the boundary and protrudes from the covered region.
    Type: Application
    Filed: January 8, 2014
    Publication date: December 10, 2015
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Hiroto Inagawa, Kenji Fukuda
  • Publication number: 20150355280
    Abstract: A power tool includes: a rechargeable battery; a motor; a drive circuit; an operation unit; a battery state detection circuit; a control circuit; and an interruption circuit. The battery state detection circuit detects a battery voltage, and when the detected battery voltage is lower than or equal to a prescribed voltage, the battery state detection circuit outputs a low-voltage signal. The control means outputs a control signal to the drive circuit instructing to drive the motor when the operation unit is operated and halts the output of the control signal to the drive circuit instructing to halt driving the motor in response to the low-voltage signal. The interruption circuit outputs an interruption signal to the drive circuit in response to the low-voltage signal to thereby interrupt the drive circuit and halt driving the motor irrespective of whether or not the control signal is outputted to the drive circuit.
    Type: Application
    Filed: January 8, 2014
    Publication date: December 10, 2015
    Applicant: HITACHI KOKI CO., LTD.
    Inventor: Kazutaka Iwata
  • Patent number: 9200558
    Abstract: An engine-driven work machine including: a two-cycle engine including a piston which is configured to reciprocally move inside a cylinder to which an exhaust port is formed; and a front end tool configured to be driven by the engine, wherein an expansion chamber is connected to the exhaust port via a connection duct, wherein the connection duct includes a first end and a second end, and the connection duct extends from the first end in an axial direction of the exhaust port, is bent in a direction away from an axis of the exhaust port and is connected to the expansion chamber at the second end, and wherein a housing of the expansion chamber is disposed at an inner side of the connection duct and an engine block including the cylinder and a crank case.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: December 1, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventor: Toshinori Yasutomi
  • Patent number: 9197153
    Abstract: A power tool includes a housing, an electric motor accommodated in the housing, a secondary battery that supplies electric power to the electric motor, a handle provided at the housing, a trigger switch provided at the handle for controlling electric power supply to the electric motor, a residual capacity display for displaying a residual capacity of the secondary battery, and a lock-release switch provided at the handle and configured to allow the trigger switch to be operable and to start displaying the residual capacity at the residual capacity display upon manipulation to the lock-release switch.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: November 24, 2015
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Kenichirou Yoshida, Hideyuki Tanimoto, Hayato Yamaguchi, Shinji Kuragano, Takuya Konnai
  • Patent number: D749389
    Type: Grant
    Filed: June 25, 2013
    Date of Patent: February 16, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshiki Aoki, Masanori Okada, Hiroyuki Hasegawa, Hiroki Uchida
  • Patent number: D752405
    Type: Grant
    Filed: March 6, 2015
    Date of Patent: March 29, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventor: Megumi Ishikawa
  • Patent number: D752406
    Type: Grant
    Filed: March 6, 2015
    Date of Patent: March 29, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventor: Ibuki Kanda
  • Patent number: D752769
    Type: Grant
    Filed: April 29, 2014
    Date of Patent: March 29, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Takeshi Taniguchi, Hiroyuki Hasegawa, Tadashi Ohkawara