Patents by Inventor Naritoshi Ohtsukasa

Naritoshi Ohtsukasa 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: 8683794
    Abstract: By accurately determining timing for suppressing overrun in a hydraulic motor or the like, work efficiency is prevented from falling. A. pressure difference ?P between pressure Pa on a discharge port side of a hydraulic pump and pressure Pb on suction port side of the hydraulic pump is calculated on the basis of the detected travel direction of the vehicle and the pressure Pa relative to Pb detected at the respective port sides of the hydraulic pump. At least one of an engine and the hydraulic pump is controlled, according to the calculated pressure difference, such that overrun of at least one of the engine, the hydraulic pump, and a hydraulic motor is suppressed.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: April 1, 2014
    Assignee: Komatsu Ltd.
    Inventors: Yuji Fukuda, Naritoshi Ohtsukasa
  • Patent number: 8438846
    Abstract: The present invention provides a hydraulic drive apparatus which can flexibly be set. The hydraulic drive apparatus which drives a variable displacement hydraulic motor 20 by a pressure oil discharged from a variable displacement hydraulic pump 10 and outputs a driving force of the hydraulic motor 20 to outside. The hydraulic drive apparatus includes torque upper limit setting unit which sets an upper limit of an output torque with respect to the hydraulic motor 20, and control unit which sets a maximum capacity limit value of the hydraulic motor 20 in accordance with the upper limit of the output torque when the upper limit of the output torque is set by the torque upper limit setting unit, and which sets a maximum capacity limit value of the hydraulic pump 10 in accordance with the upper limit of the output torque.
    Type: Grant
    Filed: January 9, 2008
    Date of Patent: May 14, 2013
    Assignee: Komatsu Ltd.
    Inventor: Naritoshi Ohtsukasa
  • Patent number: 8327638
    Abstract: The object of the present invention is to allow an operator to easily perform desired operations with high hydraulic efficiency, without an increase in difficulty of performing operations. A hydraulic drive apparatus of the present invention includes a pump control unit 31 that includes: a pump reference command value setting unit 31a that sets a pump reference command value for a hydraulic pump 10 in accordance with the engine speed of an engine 3; a pump correction command value calculating unit 31b that sets a pump command value by determining an inching rate in accordance with the amount of operation when an inching operation is performed, and correcting the pump reference command value in accordance with the inching rate; and a pump control command value setting unit 31c that sets a pump control command value for controlling the capacity of the hydraulic pump 10, based on the pump command value set by the pump correction command value calculating unit 31b.
    Type: Grant
    Filed: January 9, 2008
    Date of Patent: December 11, 2012
    Assignee: Komatsu Ltd.
    Inventor: Naritoshi Ohtsukasa
  • Publication number: 20100089051
    Abstract: The present invention provides a hydraulic drive apparatus which can flexibly be set. The hydraulic drive apparatus which drives a variable displacement hydraulic motor 20 by a pressure oil discharged from a variable displacement hydraulic pump 10 and outputs a driving force of the hydraulic motor 20 to outside. The hydraulic drive apparatus includes torque upper limit setting unit which sets an upper limit of an output torque with respect to the hydraulic motor 20, and control unit which sets a maximum capacity limit value of the hydraulic motor 20 in accordance with the upper limit of the output torque when the upper limit of the output torque is set by the torque upper limit setting unit, and which sets a maximum capacity limit value of the hydraulic pump 10 in accordance with the upper limit of the output torque.
    Type: Application
    Filed: January 9, 2008
    Publication date: April 15, 2010
    Applicant: Komastsu Ltd.
    Inventor: Naritoshi Ohtsukasa
  • Publication number: 20100083652
    Abstract: [PROBLEMS] By accurately determining timing for suppressing overrun in a hydraulic motor or the like, work efficiency is prevented from falling. [MEANS FOR SOLVING PROBLEMS] A pressure difference ?P between pressure Pa on a discharge port 1a side of a hydraulic pump 1 and pressure Pb on a suction port 1b side of the hydraulic pump 1 is calculated on the basis of the detected travel direction of the vehicle and the pressures Pa, Pb detected at the respective port 1a, 1b sides of the hydraulic pump 1. At least one of an engine 4 and the hydraulic pump 1 is controlled, according to the calculated pressure difference, such that overrun of at least one of the engine 4, the hydraulic pump 1, and a hydraulic motor 2 is suppressed.
    Type: Application
    Filed: March 27, 2008
    Publication date: April 8, 2010
    Inventors: Yuji Fukuda, Naritoshi Ohtsukasa
  • Publication number: 20090320462
    Abstract: The object of the present invention is to allow an operator to easily perform desired operations with high hydraulic efficiency, without an increase in difficulty of performing operations. A hydraulic drive apparatus of the present invention includes a pump control unit 31 that includes: a pump reference command value setting unit 31a that sets a pump reference command value for a hydraulic pump 10 in accordance with the engine speed of an engine 3; a pump correction command value calculating unit 31b that sets a pump command value by determining an inching rate in accordance with the amount of operation when an inching operation is performed, and correcting the pump reference command value in accordance with the inching rate; and a pump control command value setting unit 31c that sets a pump control command value for controlling the capacity of the hydraulic pump 10, based on the pump command value set by the pump correction command value calculating unit 31b.
    Type: Application
    Filed: January 9, 2008
    Publication date: December 31, 2009
    Inventor: Naritoshi Ohtsukasa
  • Patent number: 7143859
    Abstract: Construction machinery which is capable of improving fuel efficiency of the engine and also capable of effectively utilizing surplus energy in a light-load mode. The construction machinery includes an engine, a hydraulic pump driven by the engine, and actuators driven by oil pressure supplied from the hydraulic pump. In the light-load mode where the engine torque at the intersection point of an iso-horsepower curve of the necessary horsepower and a governor characteristic curve of the engine is smaller than that of a rated output point of the engine, the number of revolutions of the engine is reduced while the engine torque is increased with respect to the intersection point, and the horsepower is made to exceed the iso-horsepower curve. With surplus torque generated therefrom, a power generator is operated so as to generate electric power, which is stored in a power accumulation apparatus.
    Type: Grant
    Filed: September 10, 2003
    Date of Patent: December 5, 2006
    Assignee: Komatsu Ltd.
    Inventor: Naritoshi Ohtsukasa
  • Patent number: 6922990
    Abstract: A device arrangement structure for hybrid construction equipment capable of reducing devices of a charging system in size is provided. For this purpose, in the device arrangement structure: a hydraulic pump (47) is connected to an engine (41) via a first power take-off (46); and a regenerative motor (59), which is regenerated by return oil from hydraulic actuators (10a, 10b), and a generator motor (55), which assists an engine as an electric motor to drive hydraulic pump and generates power with surplus torque of the regenerative motor, are provided in parallel with the hydraulic pump via the first power take-off.
    Type: Grant
    Filed: November 4, 2003
    Date of Patent: August 2, 2005
    Assignee: Komatsu Ltd.
    Inventors: Masami Naruse, Naritoshi Ohtsukasa, Hiroyuki Inoue
  • Patent number: 6820356
    Abstract: Hybrid powered construction equipment is capable of making effective use of the output energy of an engine; increasing operating speed while keeping noise level low, and assuring operation power more than the performance of the engine. To this end, the hybrid powered construction equipment has a hydraulic pump powered by the engine; hydraulic actuators activated by discharge oil from the hydraulic pump; a motor-generator working in conjunction with the engine; and a battery for storing electric power generated by the electric motor-generator, the construction equipment further comprising a power-up switch disposed in an operating lever or operation panel and a controller which inputs a signal released from the power-up switch, wherein the controller constantly controls the revolution speed of the engine in response to a signal from the power-up switch and controls the output torque of the electric motor-generator such that torque for assisting powering of the hydraulic pump is output.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: November 23, 2004
    Assignee: Komatsu Ltd.
    Inventors: Masami Naruse, Naritoshi Ohtsukasa
  • Publication number: 20040098983
    Abstract: A device arrangement structure for hybrid construction equipment capable of reducing devices of a charging system in size is provided. For this purpose, in the device arrangement structure: a hydraulic pump (47) is connected to an engine (41) via a first power take-off (46); and a regenerative motor (59), which is regenerated by return oil from hydraulic actuators (10a, 10b), and a generator motor (55), which assists an engine as an electric motor to drive hydraulic pump and generates power with surplus torque of the regenerative motor, are provided in parallel with the hydraulic pump via the first power take-off.
    Type: Application
    Filed: November 6, 2003
    Publication date: May 27, 2004
    Applicant: KOMATSU LTD.
    Inventors: Masami Naruse, Naritoshi Ohtsukasa, Hiroyuki Inoue
  • Patent number: 6725581
    Abstract: Compact, low-cost construction equipment capable of effectively recovering energy from a plurality of hydraulic actuators is provided. To this end, the construction equipment comprises: a hydraulic recovery circuit for recovering return oil from the hydraulic actuators, the circuit being equipped with a pump motor rotatably driven by the recovered return oil; oil guide passages each of which is for guiding return oil from the meter-out side of its corresponding hydraulic actuator to the hydraulic recovery circuit; switches for switching the respective oil guide passages between their opened and closed states; pressure sensors for detecting the back pressure of each hydraulic pressure actuator; and a dynamo-electric generator for generating electric power from the rotary force of the pump motor.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: April 27, 2004
    Assignee: Komatsu Ltd.
    Inventors: Masami Naruse, Naritoshi Ohtsukasa, Junsei Tanaka, Seiya Haga
  • Publication number: 20030226291
    Abstract: Hybrid powered construction equipment is provided which is capable of making effective use of the output energy of an engine; increasing operating speed while keeping noise level low, and assuring operation power more than the performance of the engine. To this end, the hybrid powered construction equipment has a hydraulic pump powered by the engine; hydraulic actuators activated by discharge oil from the hydraulic pump; a motor-generator working in conjunction with the engine; and a battery for storing electric power generated by the electric motor-generator, the construction equipment further comprising a power-up switch disposed in an operating lever or operation panel and a controller which inputs a signal released from the power-up switch, wherein the controller constantly controls the revolution speed of the engine in response to a signal from the power-up switch and controls the output torque of the electric motor-generator such that torque for assisting powering of the hydraulic pump is output.
    Type: Application
    Filed: March 13, 2003
    Publication date: December 11, 2003
    Applicant: KOMATSU LTD.
    Inventors: Masami Naruse, Naritoshi Ohtsukasa
  • Publication number: 20030221339
    Abstract: Compact, low-cost construction equipment capable of effectively recovering energy from a plurality of hydraulic actuators is provided. To this end, the construction equipment comprises: a hydraulic recovery circuit for recovering return oil from the hydraulic actuators, the circuit being equipped with a pump motor rotatably driven by the recovered return oil; oil guide passages each of which is for guiding return oil from the meter-out side of its corresponding hydraulic actuator to the hydraulic recovery circuit; switches for switching the respective oil guide passages between their opened and closed states; pressure sensors for detecting the back pressure of each hydraulic pressure actuator; and a dynamo-electric generator for generating electric power from the rotary force of the pump motor.
    Type: Application
    Filed: March 13, 2003
    Publication date: December 4, 2003
    Applicant: KOMATSU LTD.
    Inventors: Masami Naruse, Naritoshi Ohtsukasa, Junsei Tanaka, Seiya Haga
  • Patent number: 6315827
    Abstract: There is described an apparatus for producing a single crystal ingot capable of stably manufacturing a single crystal ingot by means of the Czochralski method, without being affected by influence of variation in extension of wires or an offset in points clamped by a clamping member. The clamping member is engaged with an engagement step formed in a single crystal which is being pulled by the CZ method, and the single crystal is pulled. The single crystal ingot manufacturing apparatus is provided with a flexible mechanism for absorbing variation in extension of the wires, in intermediate portions of the wires. Variation in extension of the wires is eliminated by means of the flexible mechanism, thereby retaining the single crystal in an upright position. Further, a sacrifice member which deforms so as to conform to the circumference of the engagement step is interposed between the clamping member and the engagement step, thereby preventing occurrence of cracking or deformation in the single crystal.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: November 13, 2001
    Assignee: Komatsu Electronics Metals Co., Ltd.
    Inventors: Shoei Kurosaka, Junsuke Tomioka, Masakazu Kobayashi, Kazuhiro Mimura, Kenji Okamura, Hiroshi Monden, Naritoshi Ohtsukasa, Hiroshi Yoshinada
  • Patent number: 6266901
    Abstract: A work machine for achieving efficient coordinated operations by a plurality of kinds of operating units, comprising first and second swivel driving members and first and second swivel joints, wherein a first swiveling base bearing a first operating unit and a second swiveling base bearing a second operating unit can swivel around a common swiveling axis independently relative to a traveling base.
    Type: Grant
    Filed: January 10, 2000
    Date of Patent: July 31, 2001
    Assignee: Komatsu Ltd.
    Inventors: Toshimasa Kanda, Norihiro Aoshiba, Michio Chamura, Hiroshi Yoshinada, Naritoshi Ohtsukasa
  • Patent number: 6077347
    Abstract: A single crystal pulling apparatus and droppage preventing device constituted so as to enable the mechanical strength required by an arm to be decreased, and to enable arm manufacturing costs to be reduced and the pulling apparatus to be made more compact, and furthermore, to eliminate the need to provide in a separate manner a mechanism for preventing single crystal droppage, and to enhance reliability and durability by not adversely affecting a clean environment during single crystal growth. The arm has a mating member, which mates with the mating portion of a single crystal, and does not allow the single crystal to drop when pulling the single crystal. The arm undergoes an attitude change to a mating position in accordance with moving a circular motion having a circular motion support point as the center of the circular motion.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: June 20, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Naritoshi Ohtsukasa, Hiroshi Yoshinada, Kazuhiro Mimura
  • Patent number: 6064918
    Abstract: Detecting section detects joint angles and the relative angle of rotation from a plurality of rotatable operating tools mounted on a single mobile platform of a construction machine. Interference distance calculator, having recorded predetermined point positions for each operating tool, derives the distances between the plurality of operating tools on the basis of the detection results and the point positions, and calculates the shortest approach distance from these distances. If this shortest approach distance is less than a prescribed set distance, anti-interference controller issues a warning to alarm via the output controller, and it outputs anti-interference control to hydraulic control section CC such that the approaching tool is halted or slowed down, or the velocity of the operating tool being approached is matched to that of the approaching tool depending on the set mode.
    Type: Grant
    Filed: January 29, 1998
    Date of Patent: May 16, 2000
    Assignee: Komatsu Ltd.
    Inventors: Naritoshi Ohtsukasa, Hiroshi Yoshinada, Kenji Okamura, Kunikazu Yanagi
  • Patent number: 6032094
    Abstract: To prevent toppling of a construction machine where a plurality of operating tools are provided on a single mobile platform, a control section detects the cylinder axial forces, joint angles and relative angle of rotation for a plurality of operating tools provided rotatably on a single mobile platform, and a moment calculator calculates a composite moment for the plurality of operating tools on the basis of these detection results and further calculates a stability value relating to toppling, from this composite moment and a reference moment.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: February 29, 2000
    Assignee: Komatsu Ltd.
    Inventors: Kunikazu Yanagi, Hiroshi Yoshinada, Naritoshi Ohtsukasa, Kenji Okamura
  • Patent number: 5975214
    Abstract: A working machine control device for construction machinery provided with a plurality of joined working arms, an attachment mounted to the leading end of the working arms and a plurality of actuators for driving the working arms and the attachment, includes a function to adjust a pushing force between the attachment and a working plane by automatically controlling at least one of the actuators. The control device also includes a load detecting unit for detecting a load applied from the working plane to the attachment, working machine posture detecting devices for detecting postures of the working arms and the attachment and a computing unit for computing the pushing force between the attachment and the working plane on the basis of output values from the load detecting unit and the working machine posture detecting devices. The computing unit outputs a component of the pushing force in a direction perpendicular to the working plane.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: November 2, 1999
    Assignee: Komatsu, Ltd.
    Inventors: Kenji Okamura, Hiroshi Yoshinada, Kunikazu Yanagi, Naritoshi Ohtsukasa