Patents by Inventor Takeki Shirai

Takeki Shirai 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: 8511896
    Abstract: A rolling device having high silencing effect and requiring no positional alignment working to the seal is provided. The rolling device includes an inner member, an outer member and a number of rolling members disposed between these inner and outer members to thereby allow the outer member to carry out relative rotational motion with respect to the inner member. In such rolling device, an end plate 24 is mounted to each end portion of the outer member. This end plate 24 is provided with an end plate body 24a, a packing member 24c disposed on an abutting surface to the outer member and a seal member 24b slidably contacting the inner member with substantially no clearance. The end plate body 24a, the packing member 24c and the seal member 24b are integrally formed.
    Type: Grant
    Filed: August 20, 2008
    Date of Patent: August 20, 2013
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Soshi Miyahara, Hideki Fujii, Kentaro Hikomoto
  • Patent number: 8302498
    Abstract: A linear actuator unit has a slide plate which is allowed to freely move along the outer rail while causing a cover to retreat. The linear actuator unit includes: an outer rail, which is formed into a cylindrical shape, and includes the slit-opening portion formed along an axial direction thereof; the slide plate (3), which is coupled to an inner block in the hollow portion through the slit-opening portion; a cover belt, which is tensioned between both ends in a longitudinal direction of the outer rail so as to cover the slit-opening portion; a belt-guiding member, which separates the cover belt from the outer rail correspondingly to movement of the slide plate; and a seal member, which seals between the belt-guiding member and the cover belt and between the belt-guiding member and the outer rail.
    Type: Grant
    Filed: September 10, 2008
    Date of Patent: November 6, 2012
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Katsuya Iida, Soshi Miyahara, Ryuji Furusawa
  • Patent number: 8220353
    Abstract: A screw device manufacturing method ensures high productivity and adequate nut strength. The disclosed screw shaft manufacturing method includes: a groove forming step of forming a loaded ball rolling groove in a flat plate; and a nut forming step of bending the flat plate into a ring to form a nut. As the groove forming step of forming of the loaded ball rolling in the flat plate is followed by the nut forming step of bending the flat plate into a ring, sufficient strength of the nut can be easily achieved. Besides, a high compression stress is left in the loaded ball rolling groove in the inner surface of the nut.
    Type: Grant
    Filed: July 4, 2006
    Date of Patent: July 17, 2012
    Assignee: THK Co., Ltd.
    Inventors: Akihiro Teramachi, Takeki Shirai, Yuji Tachikake
  • Patent number: 8166838
    Abstract: An actuator has a hollow track rail 6 having a slit 8 extending in an axial direction thereof, a movable block 7 disposed inside the track rail 6 to be movable along the track rail, and a ball screw mechanism for moving the movable block 7 along the axial direction of the track rail 6. The track rail has, in a section perpendicular to the axial direction of the track rail, a guide portion 9 for guiding movement of the movable member 7 and an extension 11 extending from the guide portion 9 so as to cover the movable member, and a width W1 of the slit 8 of the track rail formed between the opposed extensions 11 is narrower than a width W2 of the movable member. Accordingly, the actuator can provide a high rigidity in spite of compact outer dimension.
    Type: Grant
    Filed: November 15, 2004
    Date of Patent: May 1, 2012
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Masashi Konomoto
  • Patent number: 8132477
    Abstract: A ball screw device having a novel ball circulation structure suitable for a screw shaft with a large lead, optimum for downsizing and weight saving of a nut member, capable of being manufactured at low cost, and capable of exhibiting high reliability even under severe use conditions. In a ball screw device where a screw shaft and a nut member are screwed to each other through an intermediation of a large number of balls, a no-load ball path which forms an infinite circulation path for the balls is constituted by a no-load ball groove spirally formed in an inner peripheral surface of a through-hole of the nut member and by a pair of direction change grooves which communicatively couple a load rolling groove and the no-load ball groove to each other so as to complete the infinite circulation path as a closed loop.
    Type: Grant
    Filed: March 19, 2007
    Date of Patent: March 13, 2012
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Yuji Tachikake, Soshi Miyahara, Masahiko Yoshino, Takashi Sakuyama, Lina Teng, Tsutomu Togashi
  • Patent number: 8123407
    Abstract: Provided is a ball spline device, in which an outer diameter of a nut member can be downsized to the maximum while sufficiently performing an original function, and which can keep reliability while being capable of being simply manufactured at lower cost without involving time and effort in assembly, in which a nut member has a track groove which is formed on an inner peripheral surface facing a spline shaft, the balls circulating in the track groove, the track groove comprises: a linear load groove formed so as to face the ball rolling groove of the spline shaft; a linear non-load groove provided parallel to the linear load groove; and a pair of ball deflection grooves for communicably coupling the linear load groove and the linear non-load groove with each other so as to allow the balls to intercommunicate therebetween, and the ball deflection grooves forcibly change an advancing direction of the balls rolling in the ball rolling groove and cause the balls to depart from the ball rolling groove with use of
    Type: Grant
    Filed: November 13, 2007
    Date of Patent: February 28, 2012
    Assignee: THK Co., Ltd.
    Inventor: Takeki Shirai
  • Patent number: 8016486
    Abstract: A rolling guiding device makes it possible to easily provide a movement block with an endless circulation path for the balls. In one surface of a movement block opposed to a rolling groove of a raceway rail, there is formed a track groove through which balls makes an endless circulation. The track groove is includes a load straight-line groove which allows, between the track groove and the rolling groove of the raceway rail, the balls to roll while bearing a load. It also includes a pair of ball deflection grooves respectively provided at both ends of the load straight-line groove and adapted to release the balls having rolled through the straight-line groove from the load and to change their rolling direction, and a non-load straight-line groove for transferring the ball in a non-load state from one deflection groove to the other ball deflection groove.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: September 13, 2011
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Katsuhito Imai, Shinji Izumi, Yuji Tachikake
  • Publication number: 20110126648
    Abstract: A linear actuator unit has a slide plate which is allowed to freely move along the outer rail while causing a cover to retreat. The linear actuator unit includes: an outer rail, which is formed into a cylindrical shape, and includes the slit-opening portion formed along an axial direction thereof; the slide plate (3), which is coupled to an inner block in the hollow portion through the slit-opening portion; a cover belt, which is tensioned between both ends in a longitudinal direction of the outer rail so as to cover the slit-opening portion; a belt-guiding member, which separates the cover belt from the outer rail correspondingly to movement of the slide plate; and a seal member, which seals between the belt-guiding member and the cover belt and between the belt-guiding member and the outer rail.
    Type: Application
    Filed: September 10, 2008
    Publication date: June 2, 2011
    Applicant: THK CO., LTD.
    Inventors: Takeki Shirai, Katsuya Iida, Soshi Miyahara, Ryuji Furusawa
  • Patent number: 7942579
    Abstract: Provided is a rolling guide device which can be produced easily and inexpensively by achieving a reduction in the number of parts constituting a slide member (2) and a reduction in machining worker-hours therefor.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: May 17, 2011
    Assignee: THK Co., Ltd.
    Inventor: Takeki Shirai
  • Patent number: 7870935
    Abstract: A traction drive power transmission device, where a lubrication oil can be stably and continuously applied for a long period to portions at which rollers and a shaft are in contact with each other, shortage of the lubrication oil does not occur at the contact portions, the lubrication oil is not wasted, and which does not impair work environment by contaminating floor surface etc. A traction drive power transmission device has at least one drive roller (12a), a follower roller (12b), and a circular cylinder-like shaft (11). The shaft (11) is held between the drive roller (12a) and the follower roller (12b). When the drive roller (12a) is rotated, rotational force by the rotation is transmitted to the shaft (11) to drive it in its axial direction. The device has a lubrication oil-delivering portion (20) with application bodies (22-1, 22-2) for applying a lubrication oil only to portions where the shaft (11) is in contact with the drive roller (12a) and the follower roller (12b).
    Type: Grant
    Filed: December 26, 2003
    Date of Patent: January 18, 2011
    Assignees: THK Co., Ltd., Mitutoyo Corporation
    Inventors: Daisuke Yatsushiro, Takeki Shirai, Hidekazu Michioka, Takahiro Kawaguchi, Haruo Kusakabe, Mitsuru Fukuda, Seiichi Otsubo
  • Patent number: 7845854
    Abstract: A motion guide device 10 includes a track rail 11 as a track member and a movable member 13 mounted to the track rail 11 via a plurality of balls 12. The plural balls 12 of the motion guide device 10 are disposed in an endless circulation passage 20 composed of a loaded rolling passage 15 formed between the track rail 11 and the movable member 13, and a non-loaded rolling passage formed to the movable member 13 so as to connect one and another ends of the loaded rolling passage 15. A portion of the track rail 11 or movable member 13 in the vicinity of the rolling member rolling surface thereof contacting to the plural balls 12 is formed of a metal material, and the other portion thereof is formed of an FRP. According to such structure, there can be provided a motion guide device 10 having a high strength and a high rigidity as well as a reduced weight.
    Type: Grant
    Filed: December 19, 2005
    Date of Patent: December 7, 2010
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Toshikazu Yoshii
  • Publication number: 20100242652
    Abstract: Provided is a ball screw device having a novel ball circulation structure suitable for a screw shaft with a large lead, optimum for downsizing and weight saving of a nut member, capable of being manufactured at low cost, and capable of exhibiting high reliability even under severe use conditions. In a ball screw device (1) where a screw shaft (2) and a nut member (3) are screwed to each other through an intermediation of a large number of balls (4), a no-load ball path (50) which forms an infinite circulation path for the balls (4) is constituted by a no-load ball groove (33a) spirally formed in an inner peripheral surface of a through-hole (30) of the nut member (3) and by a pair of direction change grooves (34) which communicatively couple a load rolling groove (20a) and the no-load ball groove (33a) to each other so as to complete the infinite circulation path as a closed loop.
    Type: Application
    Filed: March 19, 2007
    Publication date: September 30, 2010
    Applicant: THK CO., LTD.
    Inventors: Takeki Shirai, Yuji Tachikake, Soshi Miyahara, Masahiko Yoshino, Takashi Sakuyama, Lina Teng, Tsutomu Togashi
  • Publication number: 20100242651
    Abstract: Provided is a rolling-element screw device in which a recess can be easily formed in an outer diameter portion of a nut main body for receiving a circulation member. At both ends of a straight passage 5 of the nut main body 2, a pair of circulation members 8 is provided respectively, in each of which a direction change passage 6 is formed for connecting the straight passage 5 to a loaded rolling-element rolling passage 3. The circulation members 8 in a pair are fit in a pair of recesses 15, respectively, formed in the outer diameter portion of the nut main body 2. The direction change passage 6 of each circulation member 8 has a curve passage 22 which is connected to the loaded rolling-element rolling passage 3. The curve passage 22 is formed in such a way that, when seen in the axial direction of the nut main body 2, the track of the center of each rolling element 7 moving in the curve passage takes the shape of an arc.
    Type: Application
    Filed: March 25, 2010
    Publication date: September 30, 2010
    Applicant: THK CO., LTD.
    Inventors: Takeki Shirai, Katsuya Iida, Soshi Miyahara, Tsutomu Togashi
  • Publication number: 20100192711
    Abstract: A rolling device having high silencing effect and requiring no positional alignment working to the seal is provided. The rolling device includes an inner member, an outer member and a number of rolling members disposed between these inner and outer members to thereby allow the outer member to carry out relative rotational motion with respect to the inner member. In such rolling device, an end plate 24 is mounted to each end portion of the outer member. This end plate 24 is provided with an end plate body 24a, a packing member 24c disposed on an abutting surface to the outer member and a seal member 24b slidably contacting the inner member with substantially no clearance. The end plate body 24a, the packing member 24c and the seal member 24b are integrally formed.
    Type: Application
    Filed: August 20, 2008
    Publication date: August 5, 2010
    Applicant: THK CO., LTD.
    Inventors: Takeki Shirai, Soshi Miyahara, Hideki Fujii, Kentaro Hikomoto
  • Publication number: 20100101343
    Abstract: A spindle driving mechanism 5 for a machine tool includes a screw shaft 11 formed with a spiral thread groove 11a in the outer peripheral surface thereof; a ball screw nut 12 that is provided with a spiral nut groove corresponding to the thread groove 11a in the inner surface thereof, and that is configured so as to perform reciprocating motion in the axis direction of the screw shaft 11 with the rotational motion of the screw shaft 11 around the axis; a hollow motor 21 including a cylindrical inner rotor 22 fixedly provided on the outer peripheral surface of the ball screw nut 12 to serve as a field flux producing source, and a cylindrical outer stator 23 for generating a rotating magnetic field for giving a rotational driving force to the inner rotor 22; a cylindrical casing 31 on one end side of which the outer stator 23 is fixedly provided and on the other end side of which a spindle 51 for the machine tool is fixedly provided; and an outer cylinder 41 for guiding the reciprocating motion of the casing 31
    Type: Application
    Filed: March 12, 2008
    Publication date: April 29, 2010
    Inventors: Takeki Shirai, Tomozumi Murata
  • Publication number: 20100101348
    Abstract: A method of producing a screw device, having high productivity and capable of achieving sufficient strength of a nut. The method of producing a screw device has a groove forming step for previously forming a load ball rolling groove in a flat plate, which step is followed by a nut forming step for forming a nut by bending the flat plate into a ring. Since the method has, after the groove forming step in which the load rolling groove is formed in the flat plate, the nut forming step in which the flat plate is bent into a ring, sufficient strength of the nut can be easily achieved, and in addition, high compression stress is left in the load ball rolling groove in the inner diameter surface of the nut.
    Type: Application
    Filed: July 4, 2006
    Publication date: April 29, 2010
    Applicant: THK CO., LTD.
    Inventors: Akihiro Teramachi, Takeki Shirai, Yuji Tachikake
  • Publication number: 20100098358
    Abstract: Provided is a ball spline device, in which an outer diameter of a nut member can be downsized to the maximum while sufficiently performing an original function, and which can keep reliability while being capable of being simply manufactured at lower cost without involving time and effort in assembly, in which a nut member has a track groove which is formed on an inner peripheral surface facing a spline shaft, the balls circulating in the track groove, the track groove comprises: a linear load groove formed so as to face the ball rolling groove of the spline shaft; a linear non-load groove provided parallel to the linear load groove; and a pair of ball deflection grooves for communicably coupling the linear load groove and the linear non-load groove with each other so as to allow the balls to intercommunicate therebetween, and the ball deflection grooves forcibly change an advancing direction of the balls rolling in the ball rolling groove and cause the balls to depart from the ball rolling groove with use of
    Type: Application
    Filed: November 13, 2007
    Publication date: April 22, 2010
    Applicant: THK CO., LTD.
    Inventor: Takeki Shirai
  • Patent number: 7600918
    Abstract: Provided is a linear guidance device in which a track groove (30, 70) serving as an endless circulation path for balls (3) can be formed through cutting or grinding with high precision and with ease at low cost.
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: October 13, 2009
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Shigeru Ebina, Shinji Izumi, Yuki Hayashi
  • Patent number: 7592768
    Abstract: A robot joint structure ? is composed of a metacarpal member 30 and a proximal member 40 swingably connected through a hinge 31 to a side end portion of the metacarpal member 30. The proximal member 40 includes a linear guide device 44 for an MP joint having a moving member movable in association with a self swing motion thereof, and by connecting a rod 32a and the moving member through a link mechanism 50, a driving force of an air-cylinder 32 is transmitted to the proximal member 40. On the other hand, a second robot joint structure ? is also provided with linear guide devices 48, 66, 74 and link mechanisms 69, 75, to which a driving force of the air-cylinder 62 is transmitted through a drive shaft 63 in association with a rod 62a. A robot finger is constructed by the first and second robot joint structures. According to such structures, smooth joint motion can be realized, and the robot joint structure and the robot finger having improved gripping force can be provided.
    Type: Grant
    Filed: November 1, 2005
    Date of Patent: September 22, 2009
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Kaoru Hoshide, Koji Ozawa
  • Patent number: D664169
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: July 24, 2012
    Assignee: THK Co., Ltd.
    Inventors: Takeki Shirai, Katsuya Iida, Soshi Miyahara, Ryuji Furusawa