Patents by Inventor Mitsunori Hirozawa

Mitsunori Hirozawa 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: 10337171
    Abstract: Provided is a hybrid construction machine capable of appropriate control of engine speed based on a total load torque, reduction in energy loss due to the power for auxiliary devices and efficient operation of the engine and the generator motor, including a hydraulic pump, a generator motor, an engine, and a control device. The control device includes a total load torque determination section determining a total load torque, the sum of load torques for the hydraulic pump and the generator motor, and an engine speed control section controlling the engine speed based on the total load torque. The engine speed control section performs a regulation control of increasing the engine speed as the total load torque decreases under a high load torque condition and performs an isochronous control of maintaining the engine speed at a constant target speed N2 under a low load torque condition.
    Type: Grant
    Filed: January 13, 2015
    Date of Patent: July 2, 2019
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Mitsunori Hirozawa, Takayuki Doi
  • Patent number: 9777750
    Abstract: Provided is a hydraulic driving apparatus including a calculation section calculating a temporary target engine rotation speed corresponding to an engine operation amount, a calculation section calculating a temporary target pump displacement volume based on first-control and second-control target pump displacement volumes corresponding to an actuator operation amount and a pump load pressure, and a command section calculating a final target engine rotation speed and a final target pump displacement volume to output commands. The command section calculates a target pump discharge amount from the temporary target engine rotation speed and the temporary target pump displacement volume, sets the final target pump displacement volume to one larger than the temporary target pump displacement volume, and sets the final target engine rotation speed to one being lower than the temporary target engine rotation speed and allowing a pump discharge amount equivalent to the target pump discharge amount to be obtained.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: October 3, 2017
    Assignees: Kobe Steel, Ltd., KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Naoki Sugano, Takayuki Igaue, Mitsunori Hirozawa
  • Patent number: 9637890
    Abstract: A configuration is provided to directly utilize the power of an engine as the power of a hydraulic pump, and to efficiently perform power generation and engine assist. The configuration is provided with an engine; a generator which is configured to generate electric power by an operation of the generator using the power of the engine; a battery which is configured to store the electric power generated by the generator; a motor which is configured to be operated by the power of the engine and by the electric power of the battery; a hydraulic pump connected to the motor so as to be driven by operation of the motor; and a power divider connected to the engine, the generator, and the motor so that the power of the engine is distributed to the generator and to the motor.
    Type: Grant
    Filed: March 6, 2013
    Date of Patent: May 2, 2017
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventor: Mitsunori Hirozawa
  • Publication number: 20170008506
    Abstract: Provided is a hybrid construction machine capable of appropriate control of engine speed based on a total load torque, reduction in energy loss due to the power for auxiliary devices and efficient operation of the engine and the generator motor, including a hydraulic pump, a generator motor, an engine, and a control device. The control device includes a total load torque determination section determining a total load torque, the sum of load torques for the hydraulic pump and the generator motor, and an engine speed control section controlling the engine speed based on the total load torque. The engine speed control section performs a regulation control of increasing the engine speed as the total load torque decreases under a high load torque condition and performs an isochronous control of maintaining the engine speed at a constant target speed N2 under a low load torque condition.
    Type: Application
    Filed: January 13, 2015
    Publication date: January 12, 2017
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Mitsunori HIROZAWA, Takayuki DOI
  • Patent number: 9394671
    Abstract: A control device is configured to sufficiently reduce the drive loss of a hydraulic pump. The control device is provided with a controller configured to control a regeneration valve to switch to a regeneration state, and to control the flow rate of a second hydraulic pump to reduce the ejection flow rate of the second hydraulic pump in accordance with regeneration of hydraulic oil through the regeneration valve when a combined operation of lowering a boom and pressing an arm is performed. The controller outputs a command for setting the number of rotations of an engine to be smaller than the rotation number designated by a rotation number designating unit when the ejection flow rate of the second hydraulic pump is not larger than a predetermined flow rate during the combined operation.
    Type: Grant
    Filed: February 12, 2013
    Date of Patent: July 19, 2016
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Mitsunori Hirozawa, Koji Ueda
  • Patent number: 9337697
    Abstract: A hybrid construction machine that enables to efficiently cool a generator motor, while suppressing an increase in the entire length of a power unit. A motor housing is provided with a bulging portion which is configured to axially bulge from the inner periphery of a motor side connection surface toward an engine over the entire circumference thereof around an axis, and to engage with the inside of an engine housing; and a coolant passage which is configured to flow a coolant for cooling a stator therethrough. The inner peripheral surface of the motor housing including the inner peripheral surface of the bulging portion is configured to come into plane contact with the outer peripheral surface of the stator. The coolant passage is disposed at a position axially displaced from the motor side connection surface.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: May 10, 2016
    Assignee: KOBELCO CONSTRUCTIONS MACHINERY CO., LTD.
    Inventors: Mitsunori Hirozawa, Yoichiro Yamazaki
  • Patent number: 9243384
    Abstract: Provided is a hybrid construction machine preventing an electrical storage device from overcharge, including a hydraulic actuator, a hydraulic pump, a generator-motor which performs electric generator and motor actions, an engine, an electric actuator which generates regenerative electric power, an electrical storage device which performs a charge-and-discharge action with the generator-motor and the electric actuator, a charge-rate detector which detects a charge rate C1 of the electrical storage device, and a control section which controls an operation of the generator-motor and a charge-and-discharge action of the electrical storage device. The control section, when the charge rate C1 exceeds a set value Cs, performs overcharge-prevention control of making assist power by the electric motor action of the generator-motor be greater than that when C1?Cs, the set value Cs predetermined as a charge rate at which receiving the regenerative electric power can overcharge the electrical storage device.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: January 26, 2016
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Koji Yamashita, Koji Ueda, Mitsunori Hirozawa
  • Patent number: 9217239
    Abstract: Provided is a hybrid construction machine capable of preventing overcharge, comprising: an engine; a generator-motor; a hydraulic pump; a hydraulic actuator to be operated by the hydraulic pump as a hydraulic pressure source; an actuator regeneration section to make a regenerative action of generating actuator regenerated-electric-power through return fluid from the hydraulic actuator; an electric storage device; a charging-rate detector; and a control section. The control section performs: causing the electric storage device to be charged with electric power generated by the generator-motor and the actuator regenerated-electric-power; causing the generator-motor to make a motor action through electric power stored in the electric storage device to assist the engine; and a regeneration control including stopping the generator action and restricting the actuator regenerated-electric-power, when a detected charging rate of the electric storage device is not smaller than a preset charging-rate limitation value.
    Type: Grant
    Filed: August 21, 2014
    Date of Patent: December 22, 2015
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventor: Mitsunori Hirozawa
  • Publication number: 20150252820
    Abstract: Provided is a hydraulic driving apparatus including a calculation section calculating a temporary target engine rotation speed corresponding to an engine operation amount, a calculation section calculating a temporary target pump displacement volume based on first-control and second-control target pump displacement volumes corresponding to an actuator operation amount and a pump load pressure, and a command section calculating a final target engine rotation speed and a final target pump displacement volume to output commands. The command section calculates a target pump discharge amount from the temporary target engine rotation speed and the temporary target pump displacement volume, sets the final target pump displacement volume to one larger than the temporary target pump displacement volume, and sets the final target engine rotation speed to one being lower than the temporary target engine rotation speed and allowing a pump discharge amount equivalent to the target pump discharge amount to be obtained.
    Type: Application
    Filed: February 27, 2015
    Publication date: September 10, 2015
    Applicants: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.), KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Naoki SUGANO, Takayuki IGAUE, Mitsunori HIROZAWA
  • Patent number: 9077272
    Abstract: A slewing-type working machine includes: an electric storage device capable of being charged with regenerative electric power for regenerating slewing energy of an upper slewing body while functioning as an electric power source for an electric slewing motor; an electric storage device and electric storage device controller detecting whether the electric storage device is under a normal condition with sufficient capacity to regenerate the slewing energy or under an abnormal condition without sufficient capacity; and a controller controlling a velocity of the electric slewing motor based on a result of detection by the electric storage device and electric storage device controller, wherein the controller performs a velocity limiting control for limiting a maximum velocity of the electric slewing motor when the electric storage device is under the abnormal condition.
    Type: Grant
    Filed: December 28, 2011
    Date of Patent: July 7, 2015
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventor: Mitsunori Hirozawa
  • Patent number: 9062692
    Abstract: The axial lengths of coupling portions of a flywheel, a rotor shaft, and a pump shaft are reduced to reduce the axial length of an entire power unit. A crankshaft 4 and a flywheel 8 are directly coupled to each other and the flywheel 8 and a rotor shaft 5 are directly coupled to each other. A coupling 20 is directly coupled to an end face of the rotor shaft 5 on the opposite side to the flywheel 8. A pump shaft 6 is connected to the coupling 20. Coupling surfaces of the flywheel 8 and the rotor shaft 5 and coupling surfaces the rotor shaft 5 and the coupling 20 are arranged within a width range of a coil 19.
    Type: Grant
    Filed: April 5, 2012
    Date of Patent: June 23, 2015
    Assignee: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Kazushige Koiwai, Mitsunori Hirozawa, Yoichiro Yamazaki
  • Patent number: 9013051
    Abstract: Provided is a construction machine capable of achieving an energy conservation effect while restraining overcharge of an electrical storage device, including an engine, a slewing electric motor, an electrical storage device, a generator-motor, and an assist controller which causes the generator-motor to assist the engine to consume an electric power equal to or more than an electric power equal to a difference between the regeneration power and the maximum allowable charge amount, when a regeneration power regenerated by the slewing electric motor is equal to or more than a maximum allowable charge amount which is a maximum amount of an electric power within which the electrical storage device can be charged.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: April 21, 2015
    Assignee: Kobelco Construction Machinery Co., Ltd.
    Inventors: Koji Yamashita, Mitsunori Hirozawa
  • Publication number: 20150090506
    Abstract: A configuration is provided to directly utilize the power of an engine as the power of a hydraulic pump, and to efficiently perform power generation and engine assist. The configuration is provided with an engine; a generator which is configured to generate electric power by an operation of the generator using the power of the engine; a battery which is configured to store the electric power generated by the generator; a motor which is configured to be operated by the power of the engine and by the electric power of the battery; a hydraulic pump connected to the motor so as to be driven by operation of the motor; and a power divider connected to the engine, the generator, and the motor so that the power of the engine is distributed to the generator and to the motor.
    Type: Application
    Filed: March 6, 2013
    Publication date: April 2, 2015
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventor: Mitsunori Hirozawa
  • Publication number: 20150086315
    Abstract: Provided is a hybrid construction machine capable of preventing overcharge, comprising: an engine; a generator-motor; a hydraulic pump; a hydraulic actuator to be operated by the hydraulic pump as a hydraulic pressure source; an actuator regeneration section to make a regenerative action of generating actuator regenerated-electric-power through return fluid from the hydraulic actuator; an electric storage device; a charging-rate detector; and a control section. The control section performs: causing the electric storage device to be charged with electric power generated by the generator-motor and the actuator regenerated-electric-power; causing the generator-motor to make a motor action through electric power stored in the electric storage device to assist the engine; and a regeneration control including stopping the generator action and restricting the actuator regenerated-electric-power, when a detected charging rate of the electric storage device is not smaller than a preset charging-rate limitation value.
    Type: Application
    Filed: August 21, 2014
    Publication date: March 26, 2015
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventor: Mitsunori Hirozawa
  • Publication number: 20150066313
    Abstract: A control device is configured to sufficiently reduce the drive loss of a hydraulic pump. The control device is provided with a controller configured to control a regeneration valve to switch to a regeneration state, and to control the flow rate of a second hydraulic pump to reduce the ejection flow rate of the second hydraulic pump in accordance with regeneration of hydraulic oil through the regeneration valve when a combined operation of lowering a boom and pressing an arm is performed. The controller outputs a command for setting the number of rotations of an engine to be smaller than the rotation number designated by a rotation number designating unit when the ejection flow rate of the second hydraulic pump is not larger than a predetermined flow rate during the combined operation.
    Type: Application
    Filed: February 12, 2013
    Publication date: March 5, 2015
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Mitsunori Hirozawa, Koji Ueda
  • Publication number: 20150025726
    Abstract: Provided is a hybrid construction machine preventing an electrical storage device from overcharge, including a hydraulic actuator, a hydraulic pump, a generator-motor which performs electric generator and motor actions, an engine, an electric actuator which generates regenerative electric power, an electrical storage device which performs a charge-and-discharge action with the generator-motor and the electric actuator, a charge-rate detector which detects a charge rate C1 of the electrical storage device, and a control section which controls an operation of the generator-motor and a charge-and-discharge action of the electrical storage device. The control section, when the charge rate C1 exceeds a set value Cs, performs overcharge-prevention control of making assist power by the electric motor action of the generator-motor be greater than that when C1?Cs, the set value Cs predetermined as a charge rate at which receiving the regenerative electric power can overcharge the electrical storage device.
    Type: Application
    Filed: June 20, 2014
    Publication date: January 22, 2015
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Koji YAMASHITA, Koji UEDA, Mitsunori HIROZAWA
  • Publication number: 20140183876
    Abstract: Provided is a construction machine capable of achieving an energy conservation effect while restraining overcharge of an electrical storage device, including an engine, a slewing electric motor, an electrical storage device, a generator-motor, and an assist controller which causes the generator-motor to assist the engine to consume an electric power equal to or more than an electric power equal to a difference between the regeneration power and the maximum allowable charge amount, when a regeneration power regenerated by the slewing electric motor is equal to or more than a maximum allowable charge amount which is a maximum amount of an electric power within which the electrical storage device can be charged.
    Type: Application
    Filed: December 9, 2013
    Publication date: July 3, 2014
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Koji YAMASHITA, Mitsunori HIROZAWA
  • Patent number: 8726649
    Abstract: A controller includes a storage unit that stores a map in which an operation amount and an upper limit value of suction torque of a hydraulic pump are associated with each other, for each operation content identified by a cylinder that is an operation object out of the cylinders, and by a direction of operation performed on this cylinder; an operation torque determination unit that determines the upper limit value of suction torque for each cylinder by using the map stored in the storage unit when an actuation command relating to at least one cylinder is input by an operation lever; a high-level selection unit that selects the maximum upper limit value of suction torque out of the upper limit values of suction torque determined by the operation torque determination unit; and a regulator that regulates a displacement of the hydraulic pump so as to obtain torque equal to or lower than the suction torque selected by the high-level selection unit.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: May 20, 2014
    Assignees: Kabushiki Kaisha (Kobe Steel, Ltd.), Kobelco Construction Machinery Co., Ltd.
    Inventors: Takao Nanjo, Saburo Senoo, Mitsunori Hirozawa
  • Publication number: 20140026552
    Abstract: The axial lengths of coupling portions of a flywheel, a rotor shaft, and a pump shaft are reduced to reduce the axial length of an entire power unit. A crankshaft and a flywheel are directly coupled to each other and the flywheel and a rotor shaft are directly coupled to each other. A coupling is directly coupled to an end face of the rotor shaft on the opposite side to the flywheel. A pump shaft is connected to the coupling. Coupling surfaces of the flywheel and the rotor shaft and coupling surfaces the rotor shaft and the coupling are arranged within a width range of a coil.
    Type: Application
    Filed: April 5, 2012
    Publication date: January 30, 2014
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Kazushige Koiwai, Mitsunori Hirozawa, Yoichiro Yamazaki
  • Publication number: 20140026551
    Abstract: A hybrid construction machine that enables to efficiently cool a generator motor, while suppressing an increase in the entire length of a power unit. A motor housing is provided with a bulging portion which is configured to axially bulge from the inner periphery of a motor side connection surface toward an engine over the entire circumference thereof around an axis, and to engage with the inside of an engine housing; and a coolant passage which is configured to flow a coolant for cooling a stator therethrough. The inner peripheral surface of the motor housing including the inner peripheral surface of the bulging portion is configured to come into plane contact with the outer peripheral surface of the stator. The coolant passage is disposed at a position axially displaced from the motor side connection surface.
    Type: Application
    Filed: April 11, 2012
    Publication date: January 30, 2014
    Applicant: KOBELCO CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Mitsunori Hirozawa, Yoichiro Yamazaki