Patents by Inventor Kazu NAGAHAMA

Kazu NAGAHAMA 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: 11958726
    Abstract: A work machine includes: an actuator that extends and retracts a telescopic boom; an electric drive source that is provided in the actuator and drives using power supplied from a power source; an operating unit that operates based on power of the electric drive source; and a joint that has a drive-side element fixed to a first transmission shaft that rotates on the basis of the power of the electric drive source and a driven-side element fixed to a second transmission shaft connected to the operating unit, the joint being able to take a transmission state in which both the drive-side element and the driven-side element rotate and a non-transmission state in which only either the drive-side element or the driven-side element rotates.
    Type: Grant
    Filed: April 3, 2020
    Date of Patent: April 16, 2024
    Assignee: TADANO LTD.
    Inventors: Masahide Zushi, Kazu Nagahama, Toshihiko Fukuoka, Manato Shirai
  • Patent number: 11926512
    Abstract: This work machine comprises: a telescoping actuator that moves a first boom with respect to a second boom; an electrical drive source that is disposed in a movable portion of the telescoping actuator; a first biasing mechanism that maintains the connection state between the telescoping actuator and the first boom; a first connection mechanism that switches the connection state between the telescoping actuator and the first boom on the basis of the power of the electrical drive source; a second biasing mechanism that maintains the connection state between the first boom and the second boom; a second connection mechanism that switches the connection state between the first boom and the second boom on the basis of the power of the electrical drive source; and a clutch that discretionally intermittently transmits the power of the electrical drive source to the first connection mechanism and the second connection mechanism.
    Type: Grant
    Filed: August 21, 2020
    Date of Patent: March 12, 2024
    Assignee: TADANO LTD.
    Inventors: Manato Shirai, Kazu Nagahama, Masahide Zushi
  • Publication number: 20230356986
    Abstract: This work machine includes: a telescoping actuator that moves a first boom in the telescoping direction with respect to a second boom; an electrical drive source that is disposed in a movable portion of the telescoping actuator; a first connection mechanism that switches a connection state between the telescoping actuator and the first boom on the basis of the power of the electrical drive source; a second connection mechanism that switches a connection state between the first boom and the second boom on the basis of the power of the electrical drive source; and a control device that controls operation of the electrical drive source. The control device executes motor assist processing of operating the electrical drive source when the first fixing pin and/or the second fixing pin is restored by biasing force.
    Type: Application
    Filed: August 21, 2020
    Publication date: November 9, 2023
    Applicant: TADANO LTD.
    Inventors: Masahide ZUSHI, Manato SHIRAI, Kazu NAGAHAMA
  • Patent number: 11629035
    Abstract: There is provided a crane including: a telescopic boom having an inner boom element and an outer boom element; a telescoping actuator that displaces the inner boom element or the outer boom element in the telescoping direction; a first coupling member that releasably couples the telescoping actuator to one of the boom elements; a second coupling member that releasably couples the pair of boom elements to each other; an electric drive source provided at the telescoping actuator; a first coupling mechanism that displaces the first coupling member or the second coupling member on the basis of motive power of the electric drive source, thereby switching a coupled state and a non-coupled state of the members that are releasably coupled by one of the coupling members; and a position information detection device that detects information relating to the position of one of the coupling members on the basis of output from the electric drive source.
    Type: Grant
    Filed: February 14, 2019
    Date of Patent: April 18, 2023
    Assignee: TADANO LTD.
    Inventors: Masahide Zushi, Kazu Nagahama
  • Patent number: 11542131
    Abstract: This crane is configured by being provided with: a telescopic boom having an inside boom element and an outside boom element that overlap each other in an extendable and contractible manner; an extension/contraction actuator that displaces one boom element among the inside boom element and the outside boom element in the extending and contracting directions; at least one electric drive source provided in the extension/contraction actuator; a first coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the extension/contraction actuator and one of the boom elements; and a second coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the inside boom element and the outside boom element.
    Type: Grant
    Filed: February 14, 2019
    Date of Patent: January 3, 2023
    Assignee: TADANO LTD.
    Inventors: Masahide Zushi, Kazu Nagahama
  • Publication number: 20220267120
    Abstract: The work machine includes: a telescoping actuator that moves a first boom in the telescoping direction with respect to a second boom; an electrical drive source that is disposed in a movable portion of the telescoping actuator; a first connection mechanism that switches a connection state between the telescoping actuator and the first boom on the basis of the power of the electrical drive source; a second connection mechanism that switches a connection state between the first boom and the second boom on the basis of the power of the electrical drive source; and a torque limiter that is disposed between the electrical drive source and the first connection mechanism or the second connection mechanism, the torque limiter maintaining, at a predetermined value or less, a load acting on a mechanical element constituting a power transmission path from the electrical drive source.
    Type: Application
    Filed: August 21, 2020
    Publication date: August 25, 2022
    Applicant: TADANO LTD.
    Inventors: Manato SHIRAI, Kazu NAGAHAMA, Masahide ZUSHI
  • Publication number: 20220212904
    Abstract: This work machine comprises: a telescoping actuator that moves a first boom with respect to a second boom; an electrical drive source that is disposed in a movable portion of the telescoping actuator; a first biasing mechanism that maintains the connection state between the telescoping actuator and the first boom; a first connection mechanism that switches the connection state between the telescoping actuator and the first boom on the basis of the power of the electrical drive source; a second biasing mechanism that maintains the connection state between the first boom and the second boom; a second connection mechanism that switches the connection state between the first boom and the second boom on the basis of the power of the electrical drive source; and a clutch that discretionally intermittently transmits the power of the electrical drive source to the first connection mechanism and the second connection mechanism.
    Type: Application
    Filed: August 21, 2020
    Publication date: July 7, 2022
    Applicant: TADANO LTD.
    Inventors: Manato SHIRAI, Kazu NAGAHAMA, Masahide ZUSHI
  • Publication number: 20220169484
    Abstract: This work machine includes: an actuator that extends and retracts a telescopic boom; an electric drive source that is provided in the actuator and drives using power supplied from a power source; an operating unit that operates based on power of the electric drive source; an electric circuit capable of switching between a drive state in which a supply of power from the power source to the electric drive source is allowed to drive the electric drive source, and a braking state in which the supply of power from the power source to the electric drive source stops to generate a braking force to be applied to the electric drive source; and a control unit that controls the switching between the drive state and the braking state.
    Type: Application
    Filed: April 3, 2020
    Publication date: June 2, 2022
    Applicant: TADANO LTD.
    Inventors: Masahide ZUSHI, Kazu NAGAHAMA, Toshihiko FUKUOKA, Manato SHIRAI
  • Publication number: 20220169485
    Abstract: A work machine includes: an actuator that extends and retracts a telescopic boom; an electric drive source that is provided in the actuator and drives using power supplied from a power source; an operating unit that operates based on power of the electric drive source; and a joint that has a drive-side element fixed to a first transmission shaft that rotates on the basis of the power of the electric drive source and a driven-side element fixed to a second transmission shaft connected to the operating unit, the joint being able to take a transmission state in which both the drive-side element and the driven-side element rotate and a non-transmission state in which only either the drive-side element or the driven-side element rotates.
    Type: Application
    Filed: April 3, 2020
    Publication date: June 2, 2022
    Applicant: TADANO LTD.
    Inventors: Masahide ZUSHI, Kazu NAGAHAMA, Toshihiko FUKUOKA, Manato SHIRAI
  • Publication number: 20210039924
    Abstract: This crane is configured by being provided with: a telescopic boom having an inside boom element and an outside boom element that overlap each other in an extendable and contractible manner; an extension/contraction actuator that displaces one boom element among the inside boom element and the outside boom element in the extending and contracting directions; at least one electric drive source provided in the extension/contraction actuator; a first coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the extension/contraction actuator and one of the boom elements; and a second coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the inside boom element and the outside boom element.
    Type: Application
    Filed: February 14, 2019
    Publication date: February 11, 2021
    Applicant: TADANO LTD.
    Inventors: Masahide ZUSHI, Kazu NAGAHAMA
  • Publication number: 20210039926
    Abstract: There is provided a crane including: a telescopic boom having an inner boom element and an outer boom element; a telescoping actuator that displaces the inner boom element or the outer boom element in the telescoping direction; a first coupling member that releasably couples the telescoping actuator to one of the boom elements; a second coupling member that releasably couples the pair of boom elements to each other; an electric drive source provided at the telescoping actuator; a first coupling mechanism that displaces the first coupling member or the second coupling member on the basis of motive power of the electric drive source, thereby switching a coupled state and a non-coupled state of the members that are releasably coupled by one of the coupling members; and a position information detection device that detects information relating to the position of one of the coupling members on the basis of output from the electric drive source.
    Type: Application
    Filed: February 14, 2019
    Publication date: February 11, 2021
    Applicant: TADANO LTD.
    Inventors: Masahide ZUSHI, Kazu NAGAHAMA
  • Patent number: 9796566
    Abstract: A boom extension and contraction mechanism for a crane apparatus includes: a flow passage switching mechanism that switches a flow passage of the hydraulic oil between the cylinder-to-boom connection switching cylinder side and the boom member connection switching cylinder side; a hose reel configured to reel out a hydraulic hose as a telescopic cylinder is extending, and to reel off the hydraulic hose as the telescopic cylinder is contracting; a cable used to supply power and transmit a signal between a swivel base and a boom; and a cord reel configured to reel out the cable as the telescopic cylinder is extending and to reel off the cable as the telescopic cylinder is contracting. The code reel and the hose reel are arranged on the base in a direction in which the boom extends and contracts.
    Type: Grant
    Filed: August 12, 2014
    Date of Patent: October 24, 2017
    Assignee: TADANO LTD.
    Inventors: Masanori Matsuda, Kazu Nagahama
  • Publication number: 20150060385
    Abstract: A boom extension and contraction mechanism for a crane apparatus includes: a flow passage switching mechanism that switches a flow passage of the hydraulic oil between the cylinder-to-boom connection switching cylinder side and the boom member connection switching cylinder side; a hose reel configured to reel out a hydraulic hose as a telescopic cylinder is extending, and to reel off the hydraulic hose as the telescopic cylinder is contracting; a cable used to supply power and transmit a signal between a swivel base and a boom; and a cord reel configured to reel out the cable as the telescopic cylinder is extending and to reel off the cable as the telescopic cylinder is contracting. The code reel and the hose reel are arranged on the base in a direction in which the boom extends and contracts.
    Type: Application
    Filed: August 12, 2014
    Publication date: March 5, 2015
    Inventors: Masanori MATSUDA, Kazu NAGAHAMA