Patents by Inventor Takaji Iwasawa

Takaji Iwasawa 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).

  • Publication number: 20050172487
    Abstract: A method for working a nut screw for a ball screw has a first step of lathing or cutting a spiral-shaped rolling surface of the nut screw for a ball screw on which balls of the ball screw are allowed to roll, a second step of heat treating, for example, carburizing and quenching or high-frequency quenching the spiral-shaped rolling surface obtained in the first step to thereby harden the top surface layer of the rolling surface and, a third step of surface finishing the hardened top surface layer of the spiral-shaped rolling surface obtained in the second step according to an electrolytic polishing.
    Type: Application
    Filed: July 17, 2002
    Publication date: August 11, 2005
    Inventors: Toru Kamiya, Tsutomu Adachi, Takaji Iwasawa
  • Patent number: 6884151
    Abstract: A grinding apparatus for grinding a spline ball groove on a workpiece comprises a rod-shaped grindstone, having a distal end portion with a curved surface corresponding to the groove to be ground, and a spindle mechanism for rotating the grindstone. The spindle mechanism and the grindstone are supported by means of a supporter in a manner such that they are inclined at a given angle to an axis of the workpiece. A rotary dresser, which has a dress groove corresponding to the curved surface of the distal end portion of the grindstones is disposed near the grinding apparatus. The grindstone can be reciprocated along the axis of the workpiece by a drive mechanism between the workpiece and the dresser without changing its angle of inclination.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: April 26, 2005
    Assignee: NSK Ltd.
    Inventors: Akio Sakai, Takaji Iwasawa, Katsuyuki Yamamoto, Hiroyuki Ikeda, Masami Tanaka
  • Publication number: 20040219866
    Abstract: A grinding apparatus for grinding a spline ball groove on a workpiece comprises a rod-shaped grindstone, having a distal end portion with a curved surface corresponding to the groove to be ground, and a spindle mechanism for rotating the grindstone. The spindle mechanism and the grindstone are supported by means of a supporter in a manner such that they are inclined at a given angle to an axis of the workpiece. A rotary dresser, which has a dress groove corresponding to the curved surface of the distal end portion of the grindstones is disposed near the grinding apparatus. The grindstone can be reciprocated along the axis of the workpiece by a drive mechanism between the workpiece and the dresser without changing its angle of inclination.
    Type: Application
    Filed: May 28, 2004
    Publication date: November 4, 2004
    Applicant: NSK Ltd.
    Inventors: Akio Sakai, Takaji Iwasawa, Katsuyuki Yamamoto, Hiroyuki Ikeda, Masami Tanaka
  • Patent number: 6783428
    Abstract: A grinding apparatus for grinding a spline ball groove on a workpiece comprises a rod-shaped grindstone, having a distal end portion with a curved surface corresponding to the groove to be ground, and a spindle mechanism for rotating the grindstone. The spindle mechanism and the grindstone are supported by means of a supporter in a manner such that they are inclined at a given angle to an axis of the workpiece. A rotary dresser, which has a dress groove corresponding to the curved surface of the distal end portion of the grindstone, is disposed near the grinding apparatus. The grindstone can be reciprocated along the axis of the workpiece by a drive mechanism between the workpiece and the dresser without changing its angle of inclination.
    Type: Grant
    Filed: March 28, 2003
    Date of Patent: August 31, 2004
    Assignee: NSK Ltd.
    Inventors: Akio Sakai, Takaji Iwasawa, Katsuyuki Yamamoto, Hiroyuki Ikeda, Masami Tanaka
  • Patent number: 6572442
    Abstract: A grinding apparatus for grinding a spline ball groove on a workpiece comprises a rod-shaped grindstone, having a distal end portion with a curved surface corresponding to the groove to be ground, and a spindle mechanism for rotating the grindstone. The spindle mechanism and the grindstone are supported by means of a supporter in a manner such that they are inclined at a given angle to an axis of the workpiece. A rotary dresser, which has a dress groove corresponding to the curved surface of the distal end portion of the grindstone, is disposed near the grinding apparatus. The grindstone can be reciprocated along the axis of the workpiece by a drive mechanism between the workpiece and the dresser without changing its angle of inclination.
    Type: Grant
    Filed: October 25, 2001
    Date of Patent: June 3, 2003
    Assignee: NSK Ltd.
    Inventors: Akio Sakai, Takaji Iwasawa, Katsuyuki Yamamoto, Hiroyuki Ikeda, Masami Tanaka
  • Patent number: 6494807
    Abstract: While rotating a spindle 34, the circular hole 15 is worked using a cutting tool 39. Before or after the working operation of the circular hole 15, a chuck 36 is translated in a direction perpendicular to the rotation center axis of the spindle 34 by a slider 35. And, the flat surface 29 as well as the stepped surfaces 31, 31 and inner surfaces 38, 38, which are respectively composed of partially tubular surfaces, are cut or worked.
    Type: Grant
    Filed: August 8, 2000
    Date of Patent: December 17, 2002
    Assignee: NSK Ltd.
    Inventors: Yuko Kamamura, Shoji Horike, Takaji Iwasawa
  • Publication number: 20020081944
    Abstract: A grinding apparatus for grinding a spline ball groove on a workpiece comprises a rod-shaped grindstone, having a distal end portion with a curved surface corresponding to the groove to be ground, and a spindle mechanism for rotating the grindstone. The spindle mechanism and the grindstone are supported by means of a supporter in a manner such that they are inclined at a given angle to an axis of the workpiece. A rotary dresser, which has a dress groove corresponding to the curved surface of the distal end portion of the grindstone, is disposed near the grinding apparatus. The grindstone can be reciprocated along the axis of the workpiece by a drive mechanism between the workpiece and the dresser without changing its angle of inclination.
    Type: Application
    Filed: October 25, 2001
    Publication date: June 27, 2002
    Applicant: NSK Ltd.
    Inventors: Akio Sakai, Takaji Iwasawa, Katsuyuki Yamamoto, Hiroyuki Ikeda, Masami Tanaka
  • Patent number: 6361410
    Abstract: A grinding apparatus for grinding a spline ball groove on a workpiece comprises a rod-shaped grindstone, having a distal end portion with a curved surface corresponding to the groove to be ground, and a spindle mechanism for rotating the grindstone. The spindle mechanism and the grindstone are supported by means of a supporter in a manner such that they are inclined at a given angle to an axis of the workpiece. A rotary dresser, which has a dress groove corresponding to the curved surface of the distal end portion of the grindstone, is disposed near the grinding apparatus. The grindstone can be reciprocated along the axis of the workpiece by a drive mechanism between the workpiece and the dresser without changing its angle of inclination.
    Type: Grant
    Filed: January 14, 2000
    Date of Patent: March 26, 2002
    Assignee: NSK Ltd.
    Inventors: Akio Sakai, Takaji Iwasawa, Katsuyuki Yamamoto, Hiroyuki Ikeda, Masami Tanaka
  • Publication number: 20020025879
    Abstract: While rotating a spindle 34, the circular hole 15 is worked using a cutting tool 39. Before or after the working operation of the circular hole 15, a chuck 36 is translated in a direction perpendicular to the rotation center axis of the spindle 34 by a slider 35. And, the flat surface 29 as well as the stepped surfaces 31, 31 and inner surfaces 38, 38, which are respectively composed of partially tubular surfaces, are cut or worked.
    Type: Application
    Filed: August 30, 2001
    Publication date: February 28, 2002
    Applicant: NSK LTD.
    Inventors: Yuko Kamamura, Shoji Horike, Takaji Iwasawa