Patents by Inventor Koichi Saeda

Koichi Saeda 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: 5910692
    Abstract: To prevent a ball-threaded shaft from slipping out of a linear actuator, a linear actuator 10 has an output shaft 18 threaded in a nut 16 for moving forward and backward linearly with respect to an outer tube 22 secured to a housing 20. Linear reciprocating movement of the nut 16 is effected by a ball-threaded shaft 14 rotated normally and reversely by a driving motor 12. The shaft is held against axial displacement by a bearing assembly 8 having an axial disk 32 secured to a proximal end 24 of the ball-threaded shaft 14. On the nut side of the disk within the assembly are disposed a first tension receiving rotational body 36, a thrust bearing 45 and a second tension receiving rotational body 58. The assembly 8 is retained by a tension stopper 62 spread and inserted into an annular central groove 60 in the tube 22.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: June 8, 1999
    Assignee: Tsubakimoto Chain Co.
    Inventors: Koichi Saeda, Minoru Komada, Kenichiro Nakamura, Toshio Mitsuyama
  • Patent number: 5669264
    Abstract: An apparatus for preventing urging rotation of a ball screw shaft in a linear working machine includes a housing. A compressive force stopper and a tensile force stopper is contained in an outer casing of the housing. The compressive force stopper and the tensile force stopper are pressed against the compressive force receptive rotation member and the tensile force receptive rotation member respectively. A coil spring is strictly wound around an outer periphery of the compressive force receptive rotation member and the tensile force receptive rotation member. Urging rotation of the ball screw shaft by external force in an axial direction is prevented by the compressive force receptive rotation member, the tensile force receptive rotation member and the coil spring.
    Type: Grant
    Filed: October 24, 1995
    Date of Patent: September 23, 1997
    Assignee: Tsubakimoto Chain, Co.
    Inventors: Shunji Sakura, Koichi Saeda, Hiroto Sunaba, Naoto Shibata
  • Patent number: 5412174
    Abstract: A safety structure, for use in a work rotating apparatus for a laser beam machine having a manually rotatable shaft and work holder supported by a frame, comprises a pin and a pair of stops. The stops are separately located along a circular arc which is coaxial with the shaft. The stops contact the pin to limit the angle of rotation of the shaft which prevents the rotatable work holder, and the workpiece held by said work holder, from colliding with the frame.
    Type: Grant
    Filed: May 10, 1994
    Date of Patent: May 2, 1995
    Assignee: Tsubakimoto Chain, Co.
    Inventors: Koichi Saeda, Shunji Sakura
  • Patent number: 5239160
    Abstract: In a laser beam machine tool, the problems of power losses, misalignment, high cost, and other problems associated with moving laser heads are eliminated by using a five-axis table in which a biaxial work holder, capable of rotating and tilting a workpiece is mounted on a three-axis table mechanism. In the three-axis table mechanism, an X-axis table is supported on linear motion bearings in overlapping relationship on a Y-axis table, which is, in turn, supported on linear motion bearings on a vertically movable Z-axis table, which is also supported in linear motion bearings. The X-axis, Y-axis and Z-axis tables are driven by servo motors through ball screws so that backlash is avoided.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: August 24, 1993
    Assignee: Tsubakimoto Chain Co.
    Inventors: Shunji Sakura, Tatsuya Hirai, Koichi Saeda, Takashi Makino, Hiroshi Kawanaka, Masayuki Tamura
  • Patent number: 5224716
    Abstract: In a workpiece support for use with a laser beam machine tool, in which the workpiece is rotated about an axis tiltable through 90.degree. or more to either side of a vertical condition, the workpiece is held by a chuck driven through a right-angle speed reducer by a servomotor. The chuck, reducer and motor are all supported on a shaft rotatably mounted in bearings on a frame. The shaft is coupled to a disc having angle markings and lockable at discrete rotational positions on the frame. Fine adjustment of the rotational position of the shaft relative to the disc is effected by engagement of an offset protrusion on the end of the shaft by a screw-shifted operating member on the disc. Two such operating members are provided in opposed relationship on opposite sides of the protrusion so that they can be used to lock the shaft and disc securely together.
    Type: Grant
    Filed: October 8, 1991
    Date of Patent: July 6, 1993
    Assignee: Tsubakimoto Chain Co.
    Inventors: Koichi Saeda, Shunji Sakura, Tatsuya Hirai
  • Patent number: 5221824
    Abstract: A work rotating apparatus for laser machining has a reduction unit with input and output shafts, and a motor for rotating the input shaft. The output shaft is a hollow shaft having an axial through hole. A work holder, mounted on the output shaft, also has a through hole aligned with the through hole of the output shaft. A long workpiece can be held in the work holder with a part of the workpiece extending through the through hole of the work holder and into or through the through hole of the hollow output shaft. This enables the workpiece to be held more stably and securely, and allows the portion of the workpiece which is being machined to be positioned close to the work holder.In one version, the reduction unit is supported by mounting legs, enabling the work to be positioned close to the laser machine table and farther from the laser head.
    Type: Grant
    Filed: June 1, 1992
    Date of Patent: June 22, 1993
    Assignee: Tsubakimoto Chain Co.
    Inventors: Koichi Saeda, Shunji Sakura, Tatsuya Hirai, Yuko Sanada
  • Patent number: 5214980
    Abstract: A work rotating apparatus, for use in conjunction with a laser machine tool, comprises a frame, a rotatable shaft mounted on the frame for rotation on an axis, and a work mounting chuck supported by the shaft. A first disc is fixed to and rotates with the shaft. A second, stationary, disc is mounted on the frame in opposed relation to the rotatable disc. Recesses, formed on one of the discs, are positioned in circumferentially spaced relationship to one another, in a circle centered on the axis of the rotatable shaft. A spring-loaded ball detent is provided on the other disc for engagement with selected ones of the recesses. The work can be easily moved to each of several preset angles of inclination. A lock lever is provided to lock the shaft not only at the preset positions, but at any other desired position, so that any desired angle of inclination of the work can be achieved.
    Type: Grant
    Filed: June 1, 1992
    Date of Patent: June 1, 1993
    Assignee: Tsubakimoto ChainCo.
    Inventors: Koichi Saeda, Shunji Sakura, Tatsuya Hirai, Yuko Sanada
  • Patent number: 5204507
    Abstract: A work rotating device for a laser beam machine utilizes a work-supporting bed rotatable by a speed reducer mounted on a frame adapted to rest on a table of the laser beam machine. In a first embodiment, the speed reducer is fixed to the frame, and the frame has two orthogonal surfaces alternatively engageable with the table so that the axis of rotation of the work can be either vertical or horizontal. In a second embodiment, the speed reducer is manually tiltable in the frame by direct manual rotation of a shaft on which the speed reducer is mounted. In a third embodiment, the speed reducer through which the work is rotated is mounted on a shaft which is connected to a handwheel through another speed reducer. In a fourth embodiment, the speed reducer through which the work is rotated is tilted by a servo motor operating through a speed reducer.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: April 20, 1993
    Assignee: Tsubakimoto Chain Co.
    Inventors: Koichi Saeda, Shunji Sakura, Hiroshi Kawanaka, Tatsuya Hirai, Hisakazu Sakamoto, Hisaharu Terashima, Takashi Makino, Masayuki Tamura
  • Patent number: 5174586
    Abstract: A work rotating device for use with a laser beam machine tool comprises an L-shaped frame from which a servo motor, speed reducer, and a rotatable work holder are supported in cantilever fashion by a shaft rotatable in bearings provided in a hole in the frame. The shaft has an end plate haivng a spring-loaded indexing pin engageable with any selected one of several indexing holes in an indexing plate fixed to the frame. The angle of inclination of the axis of rotation of the work is read from a scale on the end plate, by means of an indexing mark on the indexing plate. The indexing plate and end plate exert axial pressure respectively on outer and inner rings of the bearings to eliminate play.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: December 29, 1992
    Assignee: Tsubakimoto Chain Co.
    Inventors: Koichi Saeda, Shunji Sakura, Tatsuya Hirai
  • Patent number: 5156382
    Abstract: In a workpiece support, a servomotor, a right-angle speed reducer and a work gripping device are supported on a horizontal shaft which is rotatable on bearings in a frame to tilt the axis of rotation of the workpiece. The shaft is locked against rotation by a lever-operated screw, which exerts a lateral force on the shaft through a lock ring. The lock ring is held against rotation by a pin which is fixed to the frame and which extends into a hole in the lock ring along an axis parallel to the axis of the screw. Fixing the lock ring against rotation prevents unintended movement of the shaft caused by tightening of the lever-operated screw. The inner surface of the lock ring is provided with an axial extending V-shaped groove which engages a spacer ring fixed on the shaft along two lines of contact for secure locking of the shaft against rotation.
    Type: Grant
    Filed: October 8, 1991
    Date of Patent: October 20, 1992
    Assignee: Tsubakimoto Chain Co.
    Inventors: Koichi Saeda, Shunji Sakura, Tatsuya Hirai