Patents by Inventor Hisami NAKANO

Hisami NAKANO 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: 11105066
    Abstract: Target speeds of an arm cylinder and a boom cylinder are computed in response to a distance D between a bucket tip end and a target surface in such a manner that an operating range of a work device is limited on and above the target surface at a time of operating an operation device. A second flow control valve that supplies a hydraulic operating fluid from a second hydraulic pump to the boom cylinder is controlled on the basis of the target speed of the boom cylinder while a first flow control valve that supplies a hydraulic operating fluid from a first hydraulic pump to the arm cylinder and a third flow control valve that supplies the hydraulic operating fluid from the second hydraulic pump to the arm cylinder are controlled on the basis of the target speed of the arm cylinder.
    Type: Grant
    Filed: March 15, 2018
    Date of Patent: August 31, 2021
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Takaaki Chiba, Hiroaki Tanaka, Hisami Nakano, Hiroshi Sakamoto, Yusuke Suzuki
  • Publication number: 20210148082
    Abstract: A work machine includes a controller (20) that performs an area restriction control for controlling at least one hydraulic cylinder (32a) of a plurality of hydraulic cylinders (32) in such a manner that a work device (400) is located on or on an upper side of an optionally set target surface (60) during operation of an operation lever (26). In the work machine, if a jack-up angle (?) as an inclination angle of a machine body (1A) relative to a ground is larger than a preset target value (?t), the controller, in performing the area restriction control, corrects the control of the at least one hydraulic cylinder (32a) in such a manner that the jack-up angle approaches the target value. The target value is set such as to vary according to posture of an arm (406).
    Type: Application
    Filed: September 3, 2018
    Publication date: May 20, 2021
    Inventors: Yusuke SUZUKI, Hiroaki TANAKA, Hisami NAKANO
  • Publication number: 20210148081
    Abstract: In a work machine including a controller (500) configured to calculate respective target velocities of a hydraulic cylinder (5) for moving a plurality of work point candidates (8a and 8b) set to a work device along an optionally set target surface (60) on the basis of positional data of the target surface, posture data of the work device (15), and operation data of an operation lever (1), and control the velocity of the hydraulic cylinder (5) according to one of a plurality of the calculated target velocities, the controller calculates a candidate point velocity (VTab or VTba) occurring in a case where each of the plurality of work point candidates is moved at the corresponding target velocity (VTa or VTb) and occurring at a remaining work point candidate, selects a velocity at which an entry into the target surface is least likely from among the plurality of candidate point velocities, and controls the hydraulic cylinder according to the target velocity of the work point candidate associated with the selecte
    Type: Application
    Filed: September 20, 2018
    Publication date: May 20, 2021
    Inventors: Hisami NAKANO, Hiroaki TANAKA, Yusuke SUZUKI
  • Patent number: 11001985
    Abstract: A controller for a hydraulic excavator includes a first speed computation section that calculates a first speed of an arm cylinder from a value detected by an operation amount sensor; a second speed computation section that calculates a second speed from a value detected by a posture sensor and a third speed computation section calculates a third speed that is used as the speed of the arm cylinder in an actuator control section adapted to execute MC (machine control). The third speed computation section calculates the first speed as the third speed during the period between the detection of an input of operation for an arm by the operation amount sensor and predetermined time to, the third speed as a speed calculated from the first speed and the second speed during the period between t0 and time t1, and the second speed as the third speed at and after time t1.
    Type: Grant
    Filed: September 13, 2017
    Date of Patent: May 11, 2021
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Masamichi Ito, Hisami Nakano, Yusuke Suzuki, Akihiro Narazaki, Teruki Igarashi
  • Publication number: 20210115643
    Abstract: To provide a work machine that can maintain the construction precision of semi-automatic control irrespective of excavation depths and differences in soil nature. A controller acquires soil-nature information on the basis of an operation command given to a work implement, a bucket-claw-tip position outputted from a bucket-position measuring device, and a drive load of the work implement outputted from a load measuring device; generates a soil-nature map on the basis of the bucket-claw-tip position, and the soil-nature information; calculates an estimated load that is an estimate of an excavation load on the basis of the soil-nature map and a bucket-claw-tip target position; and corrects the operation command in accordance with the estimated load.
    Type: Application
    Filed: June 13, 2019
    Publication date: April 22, 2021
    Applicant: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hiroaki TANAKA, Hisami NAKANO, Yuusuke SUZUKI, Hiroshi SAKAMOTO
  • Publication number: 20210062460
    Abstract: A controller mounted in a work machine limits a velocity at which a work device approaches a design surface to be equal to or lower than a predetermined limiting velocity in such a manner that the work machine is located above the design surface when an operation device is operated. The controller determines whether a work phase of the work device is compaction work on the basis of a posture of a bucket with respect to the design surface in a case in which the operation device instructs the work device to approach the design surface, and sets the limiting velocity when determining that the work phase of the work device is the compaction work to be higher than the limiting velocity when determining that the work phase of the work device is other than the compaction work.
    Type: Application
    Filed: June 6, 2019
    Publication date: March 4, 2021
    Inventors: Takaaki CHIBA, Hiroaki TANAKA, Hisami NAKANO
  • Publication number: 20210010226
    Abstract: A work machine capable of assisting in an operator's operation to allow a work tool move along a design surface indicating a target shape of an object to be worked irrespectively of an angle of the design surface and a posture of a work implement is provided. A controller determines an excavation actuator in charge of an excavation action and determines an alignment actuator in charge of an alignment action for a work tool out of a plurality of actuators on the basis of the design surface set by a work execution target setting device and the posture of the work implement measured by a work implement posture/position measurement device, determines a target velocity of the excavation actuator on the basis of operation signals outputted from an operation device, and limits a target velocity of the alignment actuator in a direction in which the work tool approaches the design surface.
    Type: Application
    Filed: June 13, 2019
    Publication date: January 14, 2021
    Inventors: Hiroaki TANAKA, Hisami NAKANO, Yuusuke SUZUKI, Hiroshi SAKAMOTO
  • Patent number: 10801524
    Abstract: A hydraulic work machine is provided which can improve the finishing accuracy in a horizontally leveling work, a slope face shaping work and so forth by preventing sudden acceleration of an arm when the excavation load decreases suddenly. The hydraulic work machine includes an arm velocity-control valve device 22 capable of adjusting a meter-out opening of the arm cylinder independently of a first arm directional control valve 23. A controller 100 is configured to control, when correcting and increasing an operation amount instructed by the first arm directional control valve, the arm velocity-control valve device to decrease the meter-out opening of the arm cylinder in response to the increase of load pressure of the arm cylinder.
    Type: Grant
    Filed: August 9, 2018
    Date of Patent: October 13, 2020
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hisami Nakano, Hidekazu Moriki
  • Publication number: 20200277751
    Abstract: Target speeds of an arm cylinder and a boom cylinder are computed in response to a distance D between a bucket tip end and a target surface in such a manner that an operating range of a work device is limited on and above the target surface at a time of operating an operation device. A second flow control valve that supplies a hydraulic operating fluid from a second hydraulic pump to the boom cylinder is controlled on the basis of the target speed of the boom cylinder while a first flow control valve that supplies a hydraulic operating fluid from a first hydraulic pump to the arm cylinder and a third flow control valve that supplies the hydraulic operating fluid from the second hydraulic pump to the arm cylinder are controlled on the basis of the target speed of the arm cylinder.
    Type: Application
    Filed: March 15, 2018
    Publication date: September 3, 2020
    Inventors: Takaaki CHIBA, Hiroaki TANAKA, Hisami NAKANO, Hiroshi SAKAMOTO, Yusuke SUZUKI
  • Publication number: 20200232186
    Abstract: A controller (25) of the hydraulic excavator (1) includes a signal separation section (150) that separates each of target speed signals for a plurality of front members (8, 9, 10) into a low frequency component and a high frequency component, a high fluctuation target speed calculation section (143) that allocates the separated high frequency components preferentially to a front member having a relatively small inertial load to calculate high fluctuation target speeds individually for the plurality of front members, a high fluctuation target actuator speed calculation section (141c) that calculates high fluctuation target speeds individually for the plurality of actuators from the high fluctuation target speeds for the plurality of front members, a low fluctuation target actuator speed calculation section (141b) that calculates low fluctuation target speeds individually for the plurality of actuators from the low frequency components separated by the signal separation section, and an actuator controller (200)
    Type: Application
    Filed: March 22, 2018
    Publication date: July 23, 2020
    Inventors: Hisami NAKANO, Hiroaki TANAKA, Yusuke SUZUKI
  • Publication number: 20200224384
    Abstract: It is determined whether a velocity estimation model is established from an actual operating velocity Vr and a target operating velocity Vt of each of actuators 20A, 21A, and 22A; in a case in which the velocity estimation model is established, a dynamic center-of-gravity position of a hydraulic excavator 1 in a case in which each of the actuators 20A, 21A, and 22A is suddenly stopped from a driven state is predicted from an estimated operating velocity Ve; in a case in which the velocity estimation model is not established, the dynamic center-of-gravity position is predicted from the actual operating velocity Vr and it is determined whether to execute control intervention using the predicted dynamic center-of-gravity position; and in a case in which it is determined to execute the control intervention, the target operating velocity Vt is corrected in such a manner that each of the actuators 20A, 21A, and 22A slowly decelerate.
    Type: Application
    Filed: March 28, 2018
    Publication date: July 16, 2020
    Inventors: Yusuke SUZUKI, Hiroaki TANAKA, Hisami NAKANO
  • Publication number: 20200217050
    Abstract: An hydraulic excavator calculates an estimated excavation volume Va defined by a bucket claw tip position (first position) at an excavation start, a bucket claw tip position (second position) at an excavation end set in advance, a current landform, a first target surface, and a bucket width w. A second target surface is generated at a position superior to the first target surface when the estimated excavation volume Va exceeds a limit volume Vb; and the second target surface is generated at a position at which the excavation volume defined by the first position, the second position, the current landform, the second target surface, and the bucket width is closer to the limit volume Vb. The hydraulic actuators are controlled such that an operating range of a work implement is limited on the second target surface and to an area superior to the second target surface.
    Type: Application
    Filed: September 6, 2017
    Publication date: July 9, 2020
    Inventors: Takaaki CHIBA, Hisami NAKANO, Hiroaki TANAKA, Manabu EDAMURA
  • Publication number: 20200181870
    Abstract: Provided is a work machine with which an operator can easily perform semi-automatic excavating shaping work at an intended excavation velocity.
    Type: Application
    Filed: November 16, 2018
    Publication date: June 11, 2020
    Inventors: Hisami NAKANO, Hiroaki TANAKA, Takaaki CHIBA, Hidekazu MORIKI
  • Publication number: 20200157768
    Abstract: A controller for a hydraulic excavator includes a first speed computation section that calculates a first speed of an arm cylinder from a value detected by an operation amount sensor; a second speed computation section that calculates a second speed from a value detected by a posture sensor and a third speed computation section calculates a third speed that is used as the speed of the arm cylinder in an actuator control section adapted to execute MC. The third speed computation section calculates the first speed as the third speed during the period between the detection of an input of operation for an arm by the operation amount sensor and predetermined time to, the third speed as a speed calculated from the first speed and the second speed during the period between t0 and time t1, and the second speed as the third speed at and after time t1.
    Type: Application
    Filed: September 13, 2017
    Publication date: May 21, 2020
    Inventors: Masamichi ITO, Hisami NAKANO, Yusuke SUZUKI, Akihiro NARAZAKI, Teruki IGARASHI
  • Publication number: 20200011030
    Abstract: A hydraulic work machine is provided which can improve the finishing accuracy in a horizontally leveling work, a slope face shaping work and so forth by preventing sudden acceleration of an arm when the excavation load decreases suddenly. The hydraulic work machine includes an arm velocity-control valve device 22 capable of adjusting a meter-out opening of the arm cylinder independently of a first arm directional control valve 23. A controller 100 is configured to control, when correcting and increasing an operation amount instructed by the first arm directional control valve, the arm velocity-control valve device to decrease the meter-out opening of the arm cylinder in response to the increase of load pressure of the arm cylinder.
    Type: Application
    Filed: August 9, 2018
    Publication date: January 9, 2020
    Inventors: Hisami NAKANO, Hidekazu MORIKI
  • Publication number: 20190390436
    Abstract: Provided is a work machine equipped with a semi-automatic control for assisting operator's operation in works to excavate the ground to form a surface as designed, which work machine can assist operator's operation in compaction works to compact the ground to form a surface as designed. In a work machine 100 including a controller 25 having a semi-automatic control section 31 that corrects an operation amount indicated by an instruction given by operation devices 15L and 15R, the controller includes: a compaction determining section 52 that determines whether or not a work tool 7 is being pressed against a ground; and an actuator control correcting section 54 that further corrects an operation amount having been corrected by the semi-automatic control section, such that a force that the work tool applies to the ground increases if the work tool is determined by the compaction determining section as being pressed against the ground.
    Type: Application
    Filed: April 25, 2018
    Publication date: December 26, 2019
    Inventors: Hiroaki TANAKA, Hisami NAKANO, Takaaki CHIBA, Yuusuke SUZUKI, Hiroshi SAKAMOTO
  • Publication number: 20190360179
    Abstract: Provided are a work point position computing section configured to compute the relative position of a work point set on a bucket with respect to an upper swing structure on the basis of posture information, a target surface setting section configured to set a target surface as a target of excavation work on the basis of design surface information, a primary operation determining section configured to determine which of operations of a boom and an arm is a primary operation as a main operation when the work point is moved along the target surface, and a recommended operation computing section configured to compute a recommended operation amount and a recommended operation direction of a secondary operation as another operation different from the primary operation in the operations of the boom and the arm according to an operation amount and an operation direction of the primary operation.
    Type: Application
    Filed: December 5, 2017
    Publication date: November 28, 2019
    Inventors: Hidekazu MORIKI, Hisami NAKANO, Hiroshi SAKAMOTO