Patents by Inventor Chikai Yoshimizu

Chikai Yoshimizu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7140451
    Abstract: A portable tool includes a motive power section, a mechanical section driven by the motive power section, and an outer frame covering the motive power section and the mechanical section. A label or a sticker is affixed to an outer peripheral surface of the outer frame. The label contains specific pattern or specific color or specific character representing a specific user of the portable tool. The cover is made from a transparent resin and is removably disposed to the outer frame for protectingly covering the label. A sheet containing a plurality of labels having colors or pattern different from each other is provided. A user can select one of the labels.
    Type: Grant
    Filed: November 28, 2003
    Date of Patent: November 28, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Chikai Yoshimizu, Masato Sakai, Toshiaki Mashiko, Mikio Kitao, Yoshihiro Komuro, Jyunichi Suzuki, Takeshi Taniguchi, Kazuhisa Hashimoto
  • Patent number: 7108079
    Abstract: A cover which covers outer peripheries of fastening screws are disposed on an outer periphery of a hammer case. A stopper which detachably positions and fixes the cover to the outer periphery of the hammer case is disposed.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: September 19, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Masato Sakai, Satoru Matsuno, Masanori Watanabe, Chikai Yoshimizu
  • Publication number: 20060170395
    Abstract: An electric device mounting type tool storage case that is easily transported together with other electric devices such as audio devices in addition to an electric tool body and can stand against contamination such as dust in the work site. An audio device as an electric device can be stored in the tool storage case which is used as an enclosure of a pair of speakers. Storage portions disposed in the tool storage case are partitioned by partition walls into a pair of sound channel spaces. In addition, a power switching circuit of an AC-DC converter power supply circuit or a battery DC power supply is formed in the tool storage case, and power wiring lines or inner wiring lines are disposed along the partition walls. While a cover case closes a storage case, electric devices such as an audio device or a charger are operated.
    Type: Application
    Filed: January 30, 2006
    Publication date: August 3, 2006
    Inventors: Chikai Yoshimizu, Eiji Nakayama, Hiroyuki Hanawa, Nobuhiro Takano
  • Publication number: 20060137887
    Abstract: A pulse torque generator utilizing a magnetic coupling, and an electric power tool provided with the pulse torque generator. The pulse torque generator includes an input shaft extending in its axial direction and having a hollow section providing a hollow space, and an output shaft rotatably provided in the hollow space. A magnetic fluid is encapsulated in a hollow space between the input shaft and output shaft. A magnetic field generating unit is disposed, and magnetic segments are provided in the input shaft. A magnetic fluid provides a magnetic fluid bridge bridging between the input shaft and the output shaft each time the magnetic segment is brought into confrontation with the magnetic field generating unit.
    Type: Application
    Filed: December 28, 2005
    Publication date: June 29, 2006
    Inventors: Shinki Ohtsu, Chikai Yoshimizu
  • Publication number: 20060131982
    Abstract: A commutator motor includes a stator and a rotor, and the stator includes a stator yoke and a field magnet. The field magnet is fixed onto the inner peripheral surface of the substantially cylindrical stator yoke. The stator yoke is configured by coaxially stacking a plurality of plate-like annular bodies, and the annular bodies are fixedly connected to each other by caulking at a caulking portion disposed on the annular body. In manufacture, the length of the stator yoke in the axial direction can be arbitrarily changed with the thickness of the annular body in the axial direction as a minimum unit. In case of manufacturing various stator yokes that are different in the axial length, the necessity of replacing a manufacturing machine is eliminated, thereby providing a commutator motor having the stator yoke which is low in the manufacturing costs.
    Type: Application
    Filed: January 25, 2006
    Publication date: June 22, 2006
    Inventors: Tomoyoshi Yokota, Shinichi Sakamoto, Chikai Yoshimizu, Katsuhiro Oomori, Tadayoshi Mineta, Kenichi Kato
  • Patent number: 7064467
    Abstract: A commutator motor includes a stator and a rotor, and the stator includes a stator yoke and a field magnet. The field magnet is fixed onto the inner peripheral surface of the substantially cylindrical stator yoke. The stator yoke is configured by coaxially stacking a plurality of plate-like annular bodies, and the annular bodies are fixedly connected to each other by caulking at a caulking portion disposed on the annular body. In manufacture, the length of the stator yoke in the axial direction can be arbitrarily changed with the thickness of the annular body in the axial direction as a minimum unit. In case of manufacturing various stator yokes that are different in the axial length, the necessity of replacing a manufacturing machine is eliminated, thereby providing a commutator motor having the stator yoke which is low in the manufacturing costs.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: June 20, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Tomoyoshi Yokota, Shinichi Sakamoto, Chikai Yoshimizu, Katsuhiro Oomori, Tadayoshi Mineta, Kenichi Kato
  • Patent number: 7048075
    Abstract: A power tool includes a powered drive source, a speed reduction mechanism portion for transmitting a rotational power of the drive source, a striking mechanism portion for converting the rotational power of the speed reduction mechanism portion into a striking force, an end tool for outputting the striking force and a rotational force through the striking mechanism portion, and an impact damping mechanism for damping the impact of the end tool in a direction of rotation of the speed reduction mechanism.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: May 23, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Takuma Saito, Shinki Ohtsu, Yasuki Ohmori, Chikai Yoshimizu, Katsuhiro Oomori, Masanori Watanabe
  • Publication number: 20060048959
    Abstract: A cover which covers outer peripheries of fastening screws are disposed on an outer periphery of a hammer case. A stopper which detachably positions and fixes the cover to the outer periphery of the hammer case is disposed.
    Type: Application
    Filed: November 1, 2005
    Publication date: March 9, 2006
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Masato Sakai, Satoru Matsuno, Masanori Watanabe, Chikai Yoshimizu
  • Publication number: 20050194929
    Abstract: In order to prevent a battery pack from being overly discharged during use in a power tool, a discharge voltage limit circuit is provided. The circuit disconnects the battery pack from the motor when the voltage of the battery pack falls below a predetermined level. However, the circuit is operable only when the main switch is OFF, that is, when no load is imposed on the motor.
    Type: Application
    Filed: March 4, 2005
    Publication date: September 8, 2005
    Inventors: Kazuhiko Funabashi, Nobuhiro Takano, Chikai Yoshimizu, Katsuhiro Oomori, Yoshihiro Komuro
  • Patent number: 6938531
    Abstract: A reciprocal-movement power tool includes a movable blade reciprocally movably provided on a main body. A receiving plate that supports an angle iron to be cut is supported on the main body at a position in front of the movable blade. The movable blade is fixed on a front tip of a rod-shaped shuttle screw. The shuttle screw moves back and forth in the axial direction within a tubular screw shaft. The screw shaft is carved with a female screw portion and is rotated through a joint spindle that is deceleratingly rotated upon rotation of the motor through a deceleration means. The shuttle screw has a male screw portion that is threadingly engageable with the female screw portion.
    Type: Grant
    Filed: February 2, 2001
    Date of Patent: September 6, 2005
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Chikai Yoshimizu, Masao Kikumoto, Takahiko Shimada
  • Publication number: 20050157489
    Abstract: A power tool has a light unit provided at the bottom part of the handle grip. The light unit can be adjusted to change the lighting angle and can hold the desired lighting angle. The light unit thus disposed does not get in the way, the lighting angle of the light unit is variable and the emitted light does not shake, depletion of the power supply due to the light switch of the light unit being left on is prevented, shadows of the end tool are not easily produced by light from the light unit, lighting contrast is high, wiring failures and continuity faults in the light-emitting element do not occur easily, and a small, economical power tool can be provided. The light-emitting element of the light unit is a yellow LED. The light unit turns off automatically at a predetermined time after the light turns on.
    Type: Application
    Filed: January 17, 2003
    Publication date: July 21, 2005
    Inventors: Katsuhiro Oomori, Chikai Yoshimizu, Hidekazu Harada, Nobuhiro Takano
  • Patent number: 6905052
    Abstract: A power tool includes a hook portion comprising a hook holding portion 20, which is provided in a housing 1 and has engaging teeth 47 provided in a housing 1, and also comprising a hook 2 having shaft portion 30, which is inserted into the hook holding portion 20 and provided with fitting teeth 31 meshing with the engaging teeth 47, an elastic body 27 adapted to push the hook 2 against a handle portion at all times, and a slip-off preventing part holding portion adapted to move the hook 2 in a direction of an axis thereof against a force of the elastic body 2 and to cancel the mesh between the teeth to thereby enable the hook 2 to turn.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: June 14, 2005
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Masato Sakai, Takeshi Matsuoka, Chikai Yoshimizu, Masanori Watanabe, Katsuhiro Oomori, Takuya Teranishi
  • Publication number: 20050092792
    Abstract: A power tool includes a hook portion comprising a hook holding portion 20, which is provided in a housing 1 and has engaging teeth 47 provided in a housing 1, and also comprising a hook 2 having a shaft portion 30, which is inserted into the hook holding portion 20 and provided with fitting teeth 31 meshing with the engaging teeth 47, an elastic body 27 adapted to push the hook 2 against a handle portion at all times, and a slip-off preventing part holding portion adapted to move the hook 2 in a direction of an axis thereof against a force of the elastic body 2 and to cancel the mesh between the teeth to thereby enable the hook 2 to turn.
    Type: Application
    Filed: October 27, 2004
    Publication date: May 5, 2005
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Masato Sakai, Takeshi Matsuoka, Chikai Yoshimizu, Masanori Watanabe, Katsuhiro Oomori, Takuya Teranishi
  • Publication number: 20050061521
    Abstract: A power tool includes an impact damping mechanism for damping an impact in a direction of rotation of a speed reduction mechanism portion 8.
    Type: Application
    Filed: September 24, 2004
    Publication date: March 24, 2005
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Takuma Saito, Shinki Ohtsu, Yasuki Ohmori, Chikai Yoshimizu, Katsuhiro Oomori, Masanori Watanabe
  • Publication number: 20040111933
    Abstract: A portable tool includes a motive power section, a mechanical section driven by the motive power section, and an outer frame covering the motive power section and the mechanical section. A label or a sticker is affixed to an outer peripheral surface of the outer frame. The label contains specific pattern or specific color or specific character representing a specific user of the portable tool. The cover is made from a transparent resin and is removably disposed to the outer frame for protectingly covering the label. A sheet containing a plurality of labels having colors or pattern different from each other is provided. A user can select one of the labels.
    Type: Application
    Filed: November 28, 2003
    Publication date: June 17, 2004
    Inventors: Chikai Yoshimizu, Masato Sakai, Toshiaki Mashiko, Mikio Kitao, Yoshihiro Komuro, Jyunichi Suzuki, Takeshi Taniguchi, Kazuhisa Hashimoto
  • Publication number: 20040074938
    Abstract: A power tool includes a hook portion comprising a hook holding portion 20, which is provided in a housing 1 and has engaging teeth 47 provided in a housing 1, and also comprising a hook 2 having a shaft portion 30, which is inserted into the hook holding portion 20 and provided with fitting teeth 31 meshing with the engaging teeth 47, an elastic body 27 adapted to push the hook 2 against a handle portion at all times, and a slip-off preventing part holding portion adapted to move the hook 2 in a direction of an axis thereof against a force of the elastic body 2 and to cancel the mesh between the teeth to thereby enable the hook 2 to turn.
    Type: Application
    Filed: December 4, 2003
    Publication date: April 22, 2004
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Masato Sakai, Takeshi Matsuoka, Chikai Yoshimizu, Masanori Watanabe, Katsuhiro Oomori, Takuya Teranishi
  • Publication number: 20040061406
    Abstract: A commutator motor includes a stator and a rotor, and the stator includes a stator yoke and a field magnet. The field magnet is fixed onto the inner peripheral surface of the substantially cylindrical stator yoke. The stator yoke is configured by coaxially stacking a plurality of plate-like annular bodies, and the annular bodies are fixedly connected to each other by caulking at a caulking portion disposed on the annular body. In manufacture, the length of the stator yoke in the axial direction can be arbitrarily changed with the thickness of the annular body in the axial direction as a minimum unit. In case of manufacturing various stator yokes that are different in the axial length, the necessity of replacing a manufacturing machine is eliminated, thereby providing a commutator motor having the stator yoke which is low in the manufacturing costs.
    Type: Application
    Filed: September 15, 2003
    Publication date: April 1, 2004
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Tomoyoshi Yokota, Shinichi Sakamoto, Chikai Yoshimizu, Katsuhiro Oomori, Tadayoshi Mineta, Kenichi Kato
  • Publication number: 20040027010
    Abstract: In a motor-driven tool, a carbon brush part 8 is arranged between a suction port 6 and a commutator 11 of the motor and includes a cylindrical side wall 8a. The cylindrical side wall 8a located on an outer periphery of the commutator 11 is provided with a tapered portion 8b which grows wider toward the commutator 11 and grows narrower toward a coil end 10 of the armature. Between the carbon brush part 8 and the coil end 10, there is provided a heat radiating plate 4 made of metal and adapted to be engaged with the carbon brush part 8.
    Type: Application
    Filed: August 6, 2003
    Publication date: February 12, 2004
    Applicant: Hitachi Koko Co., Ltd.
    Inventors: Katsuhiro Oomori, Chikai Yoshimizu, Masanori Watanabe, Toshiyuki Nemoto, Shinki Ohtsu, Takuma Saito
  • Patent number: 6679406
    Abstract: A power tool includes a hook portion comprising a hook holding portion 20, which is provided in a housing 1 and has engaging teeth 47 provided in a housing 1, and also comprising a hook 2 having a shaft portion 30, which is inserted into the hook holding portion 20 and provided with fitting teeth 31 meshing with the engaging teeth 47, an elastic body 27 adapted to push the hook 2 against a handle portion at all times, and a slip-off preventing part holding portion adapted to move the hook 2 in a direction of an axis thereof against a force of the elastic body 2 and to cancel the mesh between the teeth to thereby enable the hook 2 to turn.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: January 20, 2004
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Masato Sakai, Takeshi Matsuoka, Chikai Yoshimizu, Masanori Watanabe, Katsuhiro Oomori, Takuya Teranishi
  • Patent number: 6661148
    Abstract: In a motor-driven tool, a carbon brush part 8 is arranged between a suction port 6 and a commutator 11 of the motor and includes a cylindrical side wall 8a. The cylindrical side wall 8a located on an outer periphery of the commutator 11 is provided with a tapered portion 8b which grows wider toward the commutator 11 and grows narrower toward a coil end 10 of the armature. Between the carbon brush part 8 and the coil end 10, there is provided a heat radiating plate 4 made of metal and adapted to be engaged with the carbon brush part 8.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: December 9, 2003
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Chikai Yoshimizu, Masanori Watanabe, Shinki Ohtsu, Takuma Saito, Toshiyuki Nemoto