Patents by Inventor Yoshinori Mizumura

Yoshinori Mizumura 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: 20060260425
    Abstract: In a linear guide apparatus 1 including a rail 2 having rail track grooves 4a formed respectively in upper corner portions thereof, rail mounting holes 3 extending through the rail 2 in a direction of a height of the rail, a rail cover 16 covering the rail mounting holes 3 over an entire length of the rail, and a slider 5 for linearly moving on the rail 2, a protrusion 15, which has a width larger than a bore of the rail mounting holes 3, and extends over the entire longitudinal length of the rail 2, is formed on a rail upper surface 2a, and the rail cover 16 is mounted on this protrusion.
    Type: Application
    Filed: January 31, 2006
    Publication date: November 23, 2006
    Inventors: Yoshinori Mizumura, Wei Xu
  • Publication number: 20060243077
    Abstract: A ball screw device 10 capable of increasing a load capacity by increasing the size of ball diameter and the number of threads by preventing the cutout of a nut from being interfered with a thread groove adjacent to the cutout even in the thread groove of a small lead screw and a multiple thread screw, wherein a circulating block 18 forming, in association with the cutout 17, a ball 15 circulation passage 21 for communicating an area between both thread grooves 11 and 13 with a ball return passage 16 is fitted to the cutout 17 formed at the end of the nut 14 so that the large number of balls 15 can be endlessly circulated between both thread grooves 11 and 13, ball circulation passage 21, and ball return passage 16.
    Type: Application
    Filed: March 8, 2004
    Publication date: November 2, 2006
    Inventors: Masato Kato, Yoshinori Mizumura, Takayuki Yabe
  • Publication number: 20050109143
    Abstract: In a ball screw device comprising a screw shaft and a nut which make relative movement to each other through a multiplicity of balls, as well as in a linear motion device comprising an outer member and an inner member which make the relative movements to each other through the multiplicity of balls, a spacer having two concave surfaces facing respectively to balls, is disposed between the balls adjacent to each other. A section of each of the concave surfaces of the spacer is formed of two circular arcs of which central positions deviate from each other to form a Gothic arch. The spacer has such a configuration that the balls adjacent to each other come into contact with outer edges thereof or portions vicinal to the outer edges. The spacer also has such a configuration that the balls adjacent to each other come into contact with at least three or more outer edge portions thereof or portions vicinal to the outer edges. The spacer may have a through-hole formed in a thinnest portion thereof.
    Type: Application
    Filed: September 21, 2004
    Publication date: May 26, 2005
    Inventors: Kazuo Miyaguchi, Takeshi Nakazawa, Yoshinori Mizumura
  • Publication number: 20050076734
    Abstract: A spacer between adjacent balls of, for example, a ball screw device or a linear motion device has an outer periphery that is concave such that the spacer is elastically deformed to be in substantially circular line contact with the adjacent balls and that a distance therebetween is variable.
    Type: Application
    Filed: October 8, 2004
    Publication date: April 14, 2005
    Inventors: Kazuo Miyaguchi, Tsutomu Ohkubo, Takeshi Nakazawa, Shirouji Yabe, Soichiro Kato, Nobumitsu Takahashi, Ryouichi Sato, Hiroki Yamaguchi, Yoshinori Mizumura
  • Patent number: 6813968
    Abstract: In a ball screw device comprising a screw shaft and a nut which make relative movement to each other through a multiplicity of balls, as well as in a linear motion device comprising an outer member and an inner member which make the relative movements to each other through the multiplicity of balls, a spacer having two concave surfaces facing respectively to balls, is disposed between the balls adjacent to each other. A section of each of the concave surfaces of the spacer is formed of two circular arcs of which central positions deviate from each other to form a Gothic arch. The spacer has such a configuration that the balls adjacent to each other come into contact with outer edges thereof or portions vicinal to the outer edges. The spacer also has such a configuration that the balls adjacent to each other come into contact with at least three or more outer edge portions thereof or portions vicinal to the outer edges. The spacer may have a through-hole formed in a thinnest portion thereof.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: November 9, 2004
    Assignee: NSK Ltd.
    Inventors: Kazuo Miyaguchi, Tsutomu Ohkubo, Takeshi Nakazawa, Shirouji Yabe, Soichiro Kato, Nobumitsu Takahashi, Ryouichi Sato, Hiroki Yamaguchi, Yoshinori Mizumura
  • Patent number: 6805019
    Abstract: In a ball screw device comprising a screw shaft and a nut which make relative movement to each other through a multiplicity of balls, as well as in a linear motion device comprising an outer member and an inner member which make the relative movements to each other through the multiplicity of balls, a spacer having two concave surfaces facing respectively to balls, is disposed between the balls adjacent to each other. A section of each of the concave surfaces of the spacer is formed of two circular arcs of which central positions deviate from each other to form a Gothic arch. The spacer has such a configuration that the balls adjacent to each other come into contact with outer edges thereof or portions vicinal to the outer edges. The spacer also has such a configuration that the balls adjacent to each other come into contact with at least three or more outer edge portions thereof or portions vicinal to the outer edges. The spacer may have a through-hole formed in a thinnest portion thereof.
    Type: Grant
    Filed: January 8, 2002
    Date of Patent: October 19, 2004
    Assignee: NSK Ltd.
    Inventors: Kazuo Miyaguchi, Takeshi Nakazawa, Yoshinori Mizumura
  • Publication number: 20030194160
    Abstract: A linear guide device includes: a plurality of rolling elements; a guide rail extending in an axial direction thereof and including a plurality of rolling element rolling grooves in two side portions thereof, said rolling groove extending in an axial direction of the guide rail; a slider including a plurality of rolling element rolling grooves respectively opposed to said rolling element rolling grooves of said guide rail, said slider being supported on said guide rail in such a manner that said slider is movable along the axial direction of said guide rail through the rolling movements of said rolling elements respectively inserted between said rolling element rolling grooves of said guide rail and said rolling element rolling grooves of said slider, said slider including a rolling element endless circulation track along which said rolling elements are allowed to circulate endlessly; and a plurality of separators, each interposed between said adjoining rolling elements in the circulation direction of said ro
    Type: Application
    Filed: April 15, 2003
    Publication date: October 16, 2003
    Applicant: NSK LTD.
    Inventors: Shiroji Yabe, Soichiro Kato, Nobumitsu Takahashi, Ryoichi Sato, Yoshinori Mizumura, Hiroki Yamaguchi
  • Publication number: 20030061893
    Abstract: In a ball screw device comprising a screw shaft and a nut which make relative movement to each other through a multiplicity of balls, as well as in a linear motion device comprising an outer member and an inner member which make the relative movements to each other through the multiplicity of balls, a spacer having two concave surfaces facing respectively to balls, is disposed between the balls adjacent to each other. A section of each of the concave surfaces of the spacer is formed of two circular arcs of which central positions deviate from each other to form a Gothic arch. The spacer has such a configuration that the balls adjacent to each other come into contact with outer edges thereof or portions vicinal to the outer edges. The spacer also has such a configuration that the balls adjacent to each other come into contact with at least three or more outer edge portions thereof or portions vicinal to the outer edges. The spacer may have a through-hole formed in a thinnest portion thereof.
    Type: Application
    Filed: October 30, 2002
    Publication date: April 3, 2003
    Applicant: NSK Ltd.
    Inventors: Kazuo Miyaguchi, Tsutomu Ohkubo, Takeshi Nakazawa, Shirouji Yabe, Soichiro Kato, Nobumitsu Takahashi, Ryouichi Sato, Hiroki Yamaguchi, Yoshinori Mizumura
  • Patent number: 6510614
    Abstract: A linear guide apparatus comprises a rail and a bearing block movable in the longitudinal direction of the rail. The rail has a ground outside face. First raceway groove is formed on the outside face. Second raceway groove is formed on an inside face of the bearing block. A worked surface is formed by grinding on that portion of the inside face of the bearing block which is situated between the second raceway groove and a base portion. The worked surface and the outside face of the rail constitute a labyrinth seal portion, which serves to prevent foreign substances from getting into the raceway grooves. The worked surface and the second raceway groove of the bearing block are ground simultaneously.
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: January 28, 2003
    Assignee: NSK Ltd.
    Inventors: Soichiro Kato, Yoshinori Mizumura
  • Publication number: 20020197131
    Abstract: A mounting structure is provided for mounting a member to be fixed, on a stationary member, while always accomplishing high position precision even in such cases of fastening of members that a tightening work of bolt is carried out several times, that the members are fixed after repetition of fine adjustment of the fixing position of the member to be fixed, and so on. A screw hole for fixing according to the present invention is shaped so that on a fixing surface of the stationary member provided with the screw hole a region of an annular recess is continuous from the screw hole and annular in the external edge part of the opening portion of the screw hole, and so that when an inside diameter of the through hole in the fastened member is &phgr;a and a nominal diameter of the screw hole is b, a width c of the recess in the radial direction of the screw hole satisfies the relation of 0.5×(&phgr;a−b)<c≦2.0×(&phgr;a−b).
    Type: Application
    Filed: August 30, 2002
    Publication date: December 26, 2002
    Applicant: NSK Ltd.
    Inventors: Soichiro Kato, Hideyuki Tajimi, Yoshinori Mizumura
  • Patent number: 6464395
    Abstract: A structure is provided for mounting a member to be fixed, on a stationary member, while always accomplishing high position precision even in such cases of fastening of members that a tightening work of bolt is carried out several times, that the members are fixed after repetition of fine adjustment of the fixing position of the member to be fixed, and so on. A screw hole for fixing according to the present invention is shaped so that on a fixing surface of the stationary member provided with the screw hole a region of an annular recess is continuous from the screw hole and annular in the external edge part of the opening portion of the screw hole, and so that when an inside diameter of the through hole, in the fastened member is &phgr;a and a nominal diameter of the screw hole is b, a width c of the recess in the radial direction of the screw hole satisfies the relation of 0.5×(&phgr;a−b)<c≦2.0×(&phgr;a−b).
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: October 15, 2002
    Assignee: NSK Ltd.
    Inventors: Soichiro Kato, Hideyuki Tajimi, Yoshinori Mizumura
  • Patent number: 6435720
    Abstract: A linear guide device is provided with a plurality of rolling elements. A guide rail extending in an axial direction thereof and including a plurality of rolling element rolling grooves in two side portions thereof is provided in the device, wherein the rolling grooves extend in an axial direction of the guide rail. A slider includes a plurality of rolling element rolling grooves respectively opposed to the rolling element rolling grooves of the guide rail, wherein the slider is supported on the guide rail in such a manner that the slider is movable along the axial direction of the guide rail through the rolling movements of the rolling elements respectively inserted between the rolling element rolling grooves of the slider. The slider includes a rolling element endless circulation track along which the rolling elements are allowed to circulate endlessly; and a plurality of separators, each interposed between the adjoining rolling elements in the circulation direction of the rolling elements.
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: August 20, 2002
    Assignee: NSK Ltd.
    Inventors: Shiroji Yabe, Soichiro Kato, Nobumitsu Takahashi, Ryoichi Sato, Yoshinori Mizumura, Hiroki Yamaguchi
  • Publication number: 20020088294
    Abstract: In a ball screw device comprising a screw shaft and a nut which make relative movement to each other through a multiplicity of balls, as well as in a linear motion device comprising an outer member and an inner member which make the relative movements to each other through the multiplicity of balls, a spacer having two concave surfaces facing respectively to balls, is disposed between the balls adjacent to each other. A section of each of the concave surfaces of the spacer is formed of two circular arcs of which central positions deviate from each other to form a Gothic arch. The spacer has such a configuration that the balls adjacent to each other come into contact with outer edges thereof or portions vicinal to the outer edges. The spacer also has such a configuration that the balls adjacent to each other come into contact with at least three or more outer edge portions thereof or portions vicinal to the outer edges. The spacer may have a through-hole formed in a thinnest portion thereof.
    Type: Application
    Filed: January 8, 2002
    Publication date: July 11, 2002
    Applicant: NSK Ltd.
    Inventors: Kazuo Miyaguchi, Takeshi Nakazawa, Yoshinori Mizumura
  • Patent number: 6371648
    Abstract: In order to reduce the amount of play of balls in a circulation path in a linear guide device to thereby reduce the noise during the running of the linear guide device and improve the quality and productivity of the device, the communicating portion of the straight portion of a ball circulation path in a slider body and the curved portions of ball circulation paths in end caps is constituted by faucet-fitting comprising a cylindrical convex portion provided so as to extend the curved portions relative to the communicating portion and a cylinder concave portion corresponding to the cylindrical convex portion provided in the straight portion.
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: April 16, 2002
    Assignee: NSK Ltd.
    Inventors: Soichiro Kato, Shiroji Yabe, Yoshinori Mizumura, Hiroki Yamaguchi, Nobumitsu Takahashi, Ryoichi Sato
  • Patent number: 6347558
    Abstract: In a ball screw device comprising a screw shaft and a nut which make relative movement to each other through a multiplicity of balls, as well as in a linear motion device comprising an outer member and an inner member which make the relative movements to each other through the multiplicity of balls, a spacer having two concave surfaces facing respectively to balls, is disposed between the balls adjacent to each other. A section of each of the concave surfaces of the spacer is formed of two circular arcs of which central positions deviate from each other to from a Gothic. The spacer has such a configuration that the balls adjacent to each other come into contact with outer edges thereof or portions vicinal to the outer edges. The spacer also has such a configuration that the balls adjacent to each other come into contact with at least three or more outer portions thereof or portions vicinal to the outer edges. The spacer may have a through-hole formed in a thinnest portion thereof.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: February 19, 2002
    Assignee: NSK Ltd.
    Inventors: Kazuo Miyaguchi, Tsutomu Ohkubo, Takeshi Nakazawa, Shirouji Yabe, Soichiro Kato, Nobumitsu Takahashi, Ryouichi Sato, Hiroki Yamaguchi, Yoshinori Mizumura
  • Patent number: 5871283
    Abstract: An intermediate cover is used to cover the surface of a guide rail existing between first and second sliders arranged on the guide rail of a linear guide device. The intermediate cover is structured such that it includes on the two ends thereof two mounting portions respectively for mounting the two ends of the cover onto the two sliders, and it also includes a body portion having a U-shaped section and including an upper surface and two side surfaces located adjacent to the upper surface and two side surfaces of the guide rail.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: February 16, 1999
    Assignee: NSK Ltd.
    Inventors: Rinzo Isobe, Toru Tsukada, Yoshinori Mizumura
  • Patent number: 4986508
    Abstract: An attaching device for a bellows type dust cover of a linear guide apparatus includes a plate-shape main body and a bellows attaching plate portion integral with the plate-shape main body. The plate-shape main body has fitting plate portions which are formed by bending lower edge portions of both lateral side plate portions respectively inwardly at right angles so that both the fitting plate portions horizontally oppose each other. The fitting plate portions are respectively fitted into ball rolling grooves formed in both lateral sides of a guide rail, or into retainer relief grooves formed in groove bottoms of the ball rolling grooves. Thus, the plate-shape main body straddles an upper surface of the guide rail and sandwiches both lateral sides of the guide rail so that it is securely held to the guide rail. The bellows attaching plate portion is provided at one axial end of the plate-shape main body perpendicularly to the upper surface of the plate-shape main body.
    Type: Grant
    Filed: November 21, 1989
    Date of Patent: January 22, 1991
    Assignee: Nippon Seiko Kabushiki Kaisha
    Inventors: Nobuyuki Osawa, Yoshinori Mizumura