Patents by Inventor Yoshinori OOWADA

Yoshinori OOWADA 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).

  • Hydraulic circuit for counterweight attaching/detaching device
    Patent number: 8702061
    Abstract: A first cutoff valve is disposed in a main duct ranging between a control valve and a bottom chamber of a hydraulic cylinder. A sequence valve in the first cutoff valve is disposed along such a direction as to control outflow of a hydraulic fluid from the bottom chamber and the hydraulic pressure in a rod chamber is applied to the sequence valve as an external pilot pressure. A second cutoff valve is disposed in a main duct ranging between the control valve and the rod chamber of the hydraulic cylinder. A sequence valve in the second cutoff valve, disposed along such a direction as to control outflow of the hydraulic fluid from the rod chamber, and the hydraulic pressure in the rod chamber is applied to the sequence valve as an internal pilot pressure.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: April 22, 2014
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Daisuke Suzuki, Isao Oosato, Hirokazu Shimomura, Yoshinori Oowada
  • HYDRAULIC CIRCUIT FOR COUNTERWEIGHT ATTACHING/DETACHING DEVICE
    Publication number: 20130001492
    Abstract: A first cutoff valve is disposed in a main duct ranging between a control valve and a bottom chamber of a hydraulic cylinder. A sequence valve in the first cutoff valve is disposed along such a direction as to control outflow of a hydraulic fluid from the bottom chamber and the hydraulic pressure in a rod chamber is applied to the sequence valve as an external pilot pressure. A second cutoff valve is disposed in a main duct ranging between the control valve and the rod chamber of the hydraulic cylinder. A sequence valve in the second cutoff valve, disposed along such a direction as to control outflow of the hydraulic fluid from the rod chamber, and the hydraulic pressure in the rod chamber is applied to the sequence valve as an internal pilot pressure.
    Type: Application
    Filed: June 22, 2012
    Publication date: January 3, 2013
    Applicant: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Daisuke SUZUKI, Isao OOSATO, Hirokazu SHIMOMURA, Yoshinori OOWADA