Patents by Inventor Hideo Karasawa

Hideo Karasawa 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: 8560185
    Abstract: A target speed setting section sets a target speed of an engine to an idle speed that is lower than an input speed with an engine control dial when no operating signal is output from a control lever over a predetermined period of time. A speed control section controls the speed of the engine based on the target speed set by the target speed setting section, which includes an idle speed setting section that corrects the idle speed according to values detected by sensors so that reduction in an output of the engine due to a change in a state quantity associated with an environment under which the engine is placed can be inhibited. This allows a good operating condition to be achieved during a reset from an auto idle state even with an engine output has been reduced according to a change in environment.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: October 15, 2013
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Akihiro Narazaki, Hideo Karasawa, Tsuyoshi Nakamura
  • Patent number: 8521374
    Abstract: A hydraulic working machine, typically a hydraulic excavator has a travel speed control unit and a boost control unit. The travel speed control unit includes a traveling, hydraulic pressure oil feed unit capable of feeding pressure oil to actuate traveling tilt-angle control devices. The boost control unit includes a boosting, hydraulic pressure oil feed unit capable of feeding pressure oil to actuate an adjustable relief valve. A single hydraulic pressure oil feed unit is commonly usable as the traveling, hydraulic pressure oil feed unit and the boosting, hydraulic pressure oil feed unit, and includes lines communicating with both of the traveling tilt-angle control devices and the adjustable relief valve, a solenoid valve for opening or closing these lines, and a controller for outputting a control signal to control the solenoid valve.
    Type: Grant
    Filed: January 27, 2011
    Date of Patent: August 27, 2013
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hideo Karasawa, Nobuei Ariga, Tsuyoshi Nakamura
  • Publication number: 20130190994
    Abstract: A target speed setting section sets a target speed of an engine to an idle speed that is lower than an input speed with an engine control dial when no operating signal is output from a control lever over a predetermined period of time. A speed control section controls the speed of the engine based on the target speed set by the target speed setting section, which includes an idle speed setting section that corrects the idle speed according to values detected by sensors so that reduction in an output of the engine due to a change in a state quantity associated with an environment under which the engine is placed can be inhibited. This allows a good operating condition to be achieved during a reset from an auto idle state even with an engine output has been reduced according to a change in environment.
    Type: Application
    Filed: October 12, 2011
    Publication date: July 25, 2013
    Applicant: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Akihiro Narazaki, Hideo Karasawa, Tsuyoshi Nakamura
  • Patent number: 8424298
    Abstract: A pump torque control system is capable of preventing hunting due to interference between speed sensing control and control of an engine speed of a prime mover when the temperature of a hydraulic fluid is low. A maximum absorption torque is set in a regulator 31 that controls displacement volumes of hydraulic pumps 2 and 3 based on a deviation between target and actual engine speeds of a prime mover 1. A second modification factor calculating section 45 and a control gain modifying section 49, which are included in a controller 23 that performs speed sensing control to ensure that the maximum absorption torque of the hydraulic pumps 2 and 3 is reduced, change a control gain of the speed sensing control based on a value detected by the hydraulic temperature sensor 34 to ensure that the control gain is reduced as the temperature of the hydraulic fluid is reduced.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: April 23, 2013
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Nobuei Ariga, Kouji Ishikawa, Hideo Karasawa, Yasuo Okano, Kazunori Nakamura, Youichi Kowatari
  • Patent number: 8336443
    Abstract: A hydraulic circuit for a hydraulic working machine is composed of a main pump 21, a boom cylinder 11 arranged for extension or contraction by pressure oil from the main pump 21, a directional control valve 22 for controlling flows of pressure oil to be fed from the main pump 21 to a bottom chamber 11a and rod chamber 12b of the boom cylinder 11, a control unit 23 for performing a change-over control of the directional control valve 22, a pilot pump 24, a jack-up selector valve 25 for controlling a flow of pressure oil delivered from the pilot pump 24, a flow control valve 26 connected on an upstream side of the directional control valve 22 to a meter-in port of the directional control valve 22 such that the flow control valve 26 can be changed over by the jack-up selector valve 25, and a center bypass selector valve 27 connected on a downstream side of the directional control valve 22 to a center bypass port of the directional control valve 22 such that the center bypass selector valve 27 can be changed over
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: December 25, 2012
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Toshihiro Abe, Yusuke Kajita, Kazunori Nakamura, Kouji Ishikawa, Hideo Karasawa
  • Publication number: 20120310492
    Abstract: A hydraulic working machine, typically a hydraulic excavator has a travel speed control unit and a boost control unit. The travel speed control unit includes a traveling, hydraulic pressure oil feed unit capable of feeding pressure oil to actuate traveling tilt-angle control devices. The boost control unit includes a boosting, hydraulic pressure oil feed unit capable of feeding pressure oil to actuate an adjustable relief valve. A single hydraulic pressure oil feed unit is commonly usable as the traveling, hydraulic pressure oil feed unit and the boosting, hydraulic pressure oil feed unit, and includes lines communicating with both of the traveling tilt-angle control devices and the adjustable relief valve, a solenoid valve for opening or closing these lines, and a controller for outputting a control signal to control the solenoid valve.
    Type: Application
    Filed: January 27, 2011
    Publication date: December 6, 2012
    Applicant: HITACHI CONSTRUCTION MACHINERY CO LTD
    Inventors: Hideo Karasawa, Nobuei Ariga, Tsuyoshi Nakamura
  • Patent number: 8266903
    Abstract: An engine lag down control system for construction machinery has a machinery body controller having first, second and third torque control units and a solenoid valve. The first torque control unit controls a torque control valve to a minimum pump torque corresponding to a target number of engine revolutions when a non-operated state of a control device has continued beyond a monitoring time. The second torque control unit controls the torque control valve such that the above-described minimum pump torque is held for a predetermined holding time subsequent to the operation of the control device from the non-operated state. The third torque control unit controls the torque control valve such that from a time point of a lapse of the predetermined holding time, the pump torque is gradually increased on a basis of a predetermined torque increment rate.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: September 18, 2012
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Yoichi Kowatari, Yasushi Arai, Kouji Ishikawa, Kazunori Nakamura, Nobuei Ariga, Hideo Karasawa, Yuuki Gotou, Motoyuki Yabuuchi
  • Patent number: 7895833
    Abstract: A hydraulic drive system is mounted on a hydraulic excavator, and is provided with a directional control valve 23 for a boom, a directional control valve 24 for an arm, a boom control device 25 for selectively controlling the directional control valve 23 for the boom, and an arm control device 26 for selectively controlling the directional control valve 24 for the arm. The directional control valves 23, 24 control a boom cylinder 6 and an arm cylinder 7, respectively, which are driven by pressure oil delivered from a main hydraulic pump 21. The hydraulic drive system is provided with a communication control unit for communicating a rod chamber 6b of the boom cylinder 6 and a bottom chamber 7a of the arm cylinder 7 with each other when a stroke of the arm control device 26 has become a predetermined amount S or greater.
    Type: Grant
    Filed: August 5, 2004
    Date of Patent: March 1, 2011
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Yusuke Kajita, Kouji Ishikawa, Hideo Karasawa
  • Publication number: 20100186402
    Abstract: A pump torque control system is capable of preventing hunting due to interference between speed sensing control and control of an engine speed of a prime mover when the temperature of a hydraulic fluid is low. A maximum absorption torque is set in a regulator 31 that controls displacement volumes of hydraulic pumps 2 and 3 based on a deviation between target and actual engine speeds of a prime mover 1. A second modification factor calculating section 45 and a control gain modifying section 49, which are included in a controller 23 that performs speed sensing control to ensure that the maximum absorption torque of the hydraulic pumps 2 and 3 is reduced, change a control gain of the speed sensing control based on a value detected by the hydraulic temperature sensor 34 to ensure that the control gain is reduced as the temperature of the hydraulic fluid is reduced.
    Type: Application
    Filed: January 30, 2008
    Publication date: July 29, 2010
    Applicant: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Nobuei Ariga, Kouji Ishikawa, Hideo Karasawa, Yasuo Okano, Kazunori Nakamura, Youichi Kowatari
  • Patent number: 7605542
    Abstract: A light-emitting device, includes: an emitter sealed with a gas emitting light caused by a microwave; a high frequency power supply section including a diamond SAW oscillator and outputting a high frequency signal being output from the diamond SAW oscillator to a subsequent stage; and a waveguide unit emitting the high frequency signal being input from the high frequency power supply section towards the emitter as the microwave.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: October 20, 2009
    Assignee: Seiko Epson Corporation
    Inventors: Hideo Karasawa, Yoshiaki Matsumoto, Masahiro Onuki, Masayasu Sakuma, Yutaka Takada
  • Publication number: 20090199552
    Abstract: A hydraulic circuit for a hydraulic working machine is composed of a main pump 21, a boom cylinder 11 arranged for extension or contraction by pressure oil from the main pump 21, a directional control valve 22 for controlling flows of pressure oil to be fed from the main pump 21 to a bottom chamber 11a and rod chamber 12b of the boom cylinder 11, a control unit 23 for performing a change-over control of the directional control valve 22, a pilot pump 24, a jack-up selector valve 25 for controlling a flow of pressure oil delivered from the pilot pump 24, a flow control valve 26 connected on an upstream side of the directional control valve 22 to a meter-in port of the directional control valve 22 such that the flow control valve 26 can be changed over by the jack-up selector valve 25, and a center bypass selector valve 27 connected on a downstream side of the directional control valve 22 to a center bypass port of the directional control valve 22 such that the center bypass selector valve 27 can be changed over
    Type: Application
    Filed: April 22, 2009
    Publication date: August 13, 2009
    Applicant: Hitachi Construction Machinery Co., Ltd.
    Inventors: Toshihiro Abe, Yusuke Kajita, Kazunori Nakamura, Kouji Ishikawa, Hideo Karasawa
  • Patent number: 7562615
    Abstract: A hydraulic circuit for a hydraulic working machine is composed of a main pump 21, a boom cylinder 11 arranged for extension or contraction by pressure oil from the main pump 21, a directional control valve 22 for controlling flows of pressure oil to be fed from the main pump 21 to a bottom chamber 11a and rod chamber 12b of the boom cylinder 11, a control unit 23 for performing a change-over control of the directional control valve 22, a pilot pump 24, a jack-up selector valve 25 for controlling a flow of pressure oil delivered from the pilot pump 24, a flow control valve 26 connected on an upstream side of the directional control valve 22 to a meter-in port of the directional control valve 22 such that the flow control valve 26 can be changed over by the jack-up selector valve 25, and a center bypass selector valve 27 connected on a downstream side of the directional control valve 22 to a center bypass port of the directional control valve 22 such that the center bypass selector valve 27 can be changed over
    Type: Grant
    Filed: January 14, 2004
    Date of Patent: July 21, 2009
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Toshihiro Abe, Yusuke Kajita, Kazunori Nakamura, Kouji Ishikawa, Hideo Karasawa
  • Patent number: 7543448
    Abstract: A computing section computes a reference revolution-speed decrease modification amount DNLR; and multiplies an engine revolution speed modification gain KNL by a reference revolution-speed decrease modification amount DNL and then DNLR, to thereby compute an engine revolution-speed decrease modification amount DND based on input change of an operation pilot pressure, which is modified in accordance with DNLR. At the time when a lever operation input from an operation command unit is changed from full stroke to half stroke, if a pump delivery pressure is in a pressure range of a pump absorption torque control region Y where the pump delivery pressure is lower than that in a region X, the reference revolution-speed decrease modification amount computing section 700v computes the modification amount DNLR to be 0, and therefore lowering of a target engine revolution speed with auto-acceleration control is not caused.
    Type: Grant
    Filed: October 5, 2005
    Date of Patent: June 9, 2009
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Kazunori Nakamura, Kouji Ishikawa, Nobuei Ariga, Hideo Karasawa, Yasuo Okano
  • Patent number: 7518457
    Abstract: A microwave generator comprises: a high-frequency power section that includes a diamond SAW oscillator and outputs a high-frequency signal outputted from the diamond SAW oscillator to a subsequent stage; and a waveguide unit that emits the high-frequency signal inputted from the high-frequency power section in a form of microwave.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: April 14, 2009
    Assignee: Seiko Epson Corporation
    Inventors: Hideo Karasawa, Yoshiaki Matsumoto, Masahiro Onuki, Masayasu Sakuma
  • Patent number: 7493112
    Abstract: Assessment information needed to calculate a used vehicle assessment value of a hydraulic excavator 10 is input to a portable telephone 20 and is then transmitted from the portable telephone 20. The transmitted assessment information is received at a manufacturer's base station 40 at a remote location. The used vehicle assessment value of the hydraulic excavator 10 is calculated based upon the received assessment information, and history information and operation information on the hydraulic excavator 10 read out from an operation information database 43 and a history database 42 in correspondence to an ID number assigned to the hydraulic excavator which is included in the assessment information.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: February 17, 2009
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hiroyuki Adachi, Toichi Hirata, Genroku Sugiyama, Hiroshi Onoue, Hideo Karasawa, Koichi Shibata, Hiroshi Watanabe, Kiyoshi Ono, Osamu Tomikawa
  • Patent number: 7434394
    Abstract: To permit using hold-side pressure oil in a first hydraulic cylinder for the acceleration of a second hydraulic cylinder upon performing a combined operation of the first and second hydraulic cylinders, a hydraulic drive system is provided with a main hydraulic pump 21, a boom cylinder 6 and an arm cylinder 7, a directional control valve 23 for a boom and a directional control valve 24 for an arm, and a boom control device 25 and an arm control device 26. The hydraulic drive system is also provided with a pressure oil feed means for feeding pressure oil in a rod chamber 6b of the boom cylinder 6 to an upstream side of the directional control valve 24 for the arm when a bottom pressure of the arm cylinder 7 has increased to a high pressure equal to or higher than a predetermined pressure. This pressure oil feed means includes a flow combiner valve 44 arranged in a reservoir line 42 which can communicate to the rod chamber 6b of the boom cylinder 6.
    Type: Grant
    Filed: April 16, 2004
    Date of Patent: October 14, 2008
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Kouji Ishikawa, Yusuke Kajita, Kazunori Nakamura, Genroku Sugiyama, Hideo Karasawa
  • Publication number: 20080245065
    Abstract: A computing section computes a reference revolution-speed decrease modification amount DNLR; and multiplies an engine revolution speed modification gain KNL by a reference revolution-speed decrease modification amount DNL and then DNLR, to thereby compute an engine revolution-speed decrease modification amount DND based on input change of an operation pilot pressure, which is modified in accordance with DNLR. At the time when a lever operation input from an operation command unit is changed from full stroke to half stroke, if a pump delivery pressure is in a pressure range of a pump absorption torque control region Y where the pump delivery pressure is lower than that in a region X, the reference revolution-speed decrease modification amount computing section 700v computes the modification amount DNLR to be 0, and therefore lowering of a target engine revolution speed with auto-acceleration control is not caused.
    Type: Application
    Filed: October 5, 2005
    Publication date: October 9, 2008
    Applicant: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Kazunori Nakamura, Kouji Ishikawa, Nobuei Ariga, Hideo Karasawa, Yasuo Okano
  • Publication number: 20080236157
    Abstract: An engine lag down suppressing device of construction machinery, comprising a vehicle body controller (13) having a first torque control means and a second torque control means, and a third torque control means. The first torque control means controls a torque control valve (7) to the minimum pump torque (value: Min) according to a target engine rotational speed (Nr) when the operating device (5) in the non-operated state of an continues for a monitoring time (TX1) to suppress an engine lag down after a specified holing time to hold a torque to a low pump torque is passed when the operating device in the non-operated state is operated. The second torque control means controls the torque control valve (7) to hold the minimum pump torque for a specified holding time (Tx2) after the operating device (5) in the non-operated state is operated.
    Type: Application
    Filed: August 27, 2004
    Publication date: October 2, 2008
    Applicant: Hitachi Construction Machinery Co., Ltd.
    Inventors: Yoichi Kowatari, Yasushi Arai, Kouji Ishikawa, Kazunori Nakamura, Nobuei Ariga, Hideo Karasawa, Yuuki Gotou, Motoyuki Yabuuchi
  • Publication number: 20080223205
    Abstract: A hydraulic drive system is mounted on a hydraulic excavator, and is provided with a directional control valve 23 for a boom, a directional control valve 24 for an arm, a boom control device 25 for selectively controlling the directional control valve 23 for the boom, and an arm control device 26 for selectively controlling the directional control valve 24 for the arm. The directional control valves 23,24 control a boom cylinder 6 and an arm cylinder 7, respectively, which are driven by pressure oil delivered from a main hydraulic pump 21. The hydraulic drive system is provided with a communication control means for communicating a rod chamber 6b of the boom cylinder 6 and a bottom chamber 7a of the arm cylinder 7 with each other when a stroke of the arm control device 26 has become a predetermined amount S or greater.
    Type: Application
    Filed: August 5, 2004
    Publication date: September 18, 2008
    Applicant: Hitachi Construction Machinery Co., Ltd.
    Inventors: Yusuke Kajita, Kouji Ishikawa, Hideo Karasawa
  • Publication number: 20070202861
    Abstract: Assessment information needed to calculate a used vehicle assessment value of a hydraulic excavator 10 is input to a portable telephone 20 and is then transmitted from the portable telephone 20. The transmitted assessment information is received at a manufacturer's base station 40 at a remote location. The used vehicle assessment value of the hydraulic excavator 10 is calculated based upon the received assessment information, and history information and operation information on the hydraulic excavator 10 read out from an operation information database 43 and a history database 42 in correspondence to an ID number assigned to the hydraulic excavator which is included in the assessment information.
    Type: Application
    Filed: April 27, 2007
    Publication date: August 30, 2007
    Applicant: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hiroyuki Adachi, Toichi Hirata, Genroku Sugiyama, Hiroshi Onoue, Hideo Karasawa, Koichi Shibata, Hiroshi Watanabe, Kiyoshi Ono, Osamu Tomikawa