Patents by Inventor Ryokichi Yamazaki

Ryokichi Yamazaki 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: 6055780
    Abstract: A retractable stairs-like stand has rows of seats on moveable floor-bases arranged in a stair-like manner for use in an auditorium or stadium-like application. A variety of seating styles can be accommodated due to the retracted storage position used wherein the steps are shifted to all be in vertical alignment, and the seats are stored in a nested configuration with corresponding seats in vertical alignment to provide a more compact arrangement.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: May 2, 2000
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki
  • Patent number: 6000174
    Abstract: A retractable, stairs-like stand includes plural steps of floor-bases which are moved horizontally between the advanced position where the floor-bases are mutually shifted into a form of stairs and the retracted position where the floor-bases are mutually lined up along the vertical direction, and plural seats fitted onto the floor-bases. The front portions of the respective floor-bases are equipped with parallel link mechanism for parallel moving the seat sections of the seats back and forth between the use-position where the seat sections of the seats are spaced from the floor-bases and the descent position where the seat sections of the seats are adjacent the floor-bases. Fastening mechanisms are disposed for selectively fixing the seat sections to the use-position and the fastening position where releasing the sections from the use-position.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: December 14, 1999
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki
  • Patent number: 5803546
    Abstract: Disclosed is a turning mechanism for a chair seat which comprises a shaft having a square cross section and fixed to the leg of a chair having a seat, a spring disposed to the shaft with an end thereof locked to the shaft and the other end thereof engaged so as to be associated with the turning of the seat of the chair, a stopper inserted into and engaged with the shaft through a square hole defined at the center thereof, a stopper receiver having abutting portions formed thereto and abutted against projections formed to the stopper, a first bush inserted into and engaged with the shaft through a square hole defined at the center thereof; and a second bush inserted into and engaged with the shaft through a square hole defined at the center thereof, wherein the first bush, the stopper and the second bush are contained in the stopper receiver. With this arrangement, there is provided a compact turning mechanism for a chair seat which is lingt in weight and small in size and can reduce an assemblying job.
    Type: Grant
    Filed: January 7, 1997
    Date of Patent: September 8, 1998
    Assignee: Kabushiki Kaisha Kotobuki
    Inventor: Ryokichi Yamazaki
  • Patent number: 5700052
    Abstract: A chair includes a main body with a seat, openings formed in the greater part of the lower surface of the seat, a sound absorbing structure contained in the seat while facing the openings, and a louver having a series of openings defined with a number of slats that may be turned for opening and closing. The louver is located in front of the series of openings. When the seat is unoccupied, the slats of the louver are turned for opening. When the seat is occupied, the slats are turned for closing. The chair is adequate for concert halls or theaters.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: December 23, 1997
    Assignee: Yamaha Corporation
    Inventors: Ryokichi Yamazaki, Takeshi Sakai, Fukushi Kawakami
  • Patent number: 5685608
    Abstract: A seat comprises a first frame rotatable between a first position where the frame is raised from a floor surface and a second position where said frame is horizontally moved down along the floor surface, and a second frame rotatable between a raise position where the frame is raised from the floor surface and a folding position where the frame is horizontally moved down along the floor surfaces at the back of the first frame. The first and second frames are interlocked each other through arm rest. A seat cushion is rotatably supported on the first frame. A back rest is supported on the second frame to be rotatable in back and forth directions through a pivot shaft. The back rest and the first frame are interlocked each other through a link member. The link member rotates the back rest in a direction where the lower end portion of the back rest is drawn forward when the first frame is rotated to the first position.
    Type: Grant
    Filed: February 21, 1996
    Date of Patent: November 11, 1997
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki
  • Patent number: 5328238
    Abstract: A layable seat includes front and rear paired supporting legs which are layably raised on a floor at two positions separated from each other in a back-and-forth direction, a seat member pivotably connected to the front paired legs, paired link levers each of which has one end pivotably connected to the corresponding one pivotal center of the seat member and the other end pivotably connected to the corresponding rear leg. The seat member is elastically held at its half-folded position by torsion coil springs, and has paired engaging pins which project sideward therefrom and engage the lower edges of the link levers to hold the seat member at its horizontal position against a user's weight.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: July 12, 1994
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki
  • Patent number: 5328239
    Abstract: A flip-up type seat has a seat member support, a seat member, and a seat member coupling mechanism interposed between the seat member support and the seat member to couple the seat member to the seat member support in such a way that the seat member can be freely moved between its horizontal seated position and its vertical flipped-up position. The seat member coupling mechanism cause the rear end of the seat member to be moved up and down in the vertical direction and the front end thereof forward and backward in the horizontal direction when the seat member is moved between its seated position and its flipped-up position.
    Type: Grant
    Filed: June 11, 1992
    Date of Patent: July 12, 1994
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki
  • Patent number: 5087096
    Abstract: An unique apparatus for displacing an extensible/contractible board for a chair in case of an occurrence of emergency is disclosed. The apparatus includes a board support, an engagement piece, a turn guide plate, a stationary guide plate and an opposing pair of base members. The board assumes a horizontal attitude during normal use. In case of emergency, an excessive magnitude of outer force in excess of resilient force derived from Belleville springs is imparted to the board by an user's hand so that the engagement piece is disengaged from the turn guide plate via operative engagement of an eccentric projection on the board shaft with an engagement recess on the engagement piece. This causes the board to be displaced from the horizontal attitude to a vertical attitude, whereby a sufficiently wide space is provided in front of the user so as to enable him to quickly escape from his chair.
    Type: Grant
    Filed: April 18, 1990
    Date of Patent: February 11, 1992
    Assignee: Kabushiki Kaisha Kotobuki
    Inventor: Ryokichi Yamazaki
  • Patent number: 4932718
    Abstract: A coupled chair unit for conversion to a desk mode of use and to a chair mode of use comprises a plurality of legs, a beam member bridged over the legs, a plurality of armrests fixed on the beam member in a longitudinal direction of the beam member, a plurality of support posts uprightly fixed on the beam member and having first and second support portions provided in the upper and lower positions, respectively, a plurality of chair seats tiltably supported between the adjacent armrests, a plurality of chair backrests including upper and lower backrest segments, movable and fixed, which are situated above the respective chair seats, an upper backrest segment-equipped table panel which is held erect behind the support post and chair backrest in an ordinary chair mode of use and a link mechanism converting the coupled chair unit to the ordinary chair mode of use in which the table panel is held erect and to a desk mode of use in which the table panel is held substantially horizontal.
    Type: Grant
    Filed: October 4, 1989
    Date of Patent: June 12, 1990
    Assignee: Kotobuki Seating Company, Ltd.
    Inventor: Ryokichi Yamazaki
  • Patent number: RE37043
    Abstract: A layable seat includes front and rear paired supporting legs which are layably raised on a floor at two positions separated from each other in a back-and-forth direction, a seat member pivotably connected to the front paired legs, paired link levers each of which has one end pivotably connected to the corresponding one pivotal center of the seat member and the other end pivotably connected to the corresponding rear leg. The seat member is elastically held at its half-folded position by torsion coil springs, and has paired engaging pins which project sideward therefrom and engage the lower edges of the link levers to hold the seat member at its horizontal position against a user's weight.
    Type: Grant
    Filed: July 11, 1996
    Date of Patent: February 6, 2001
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki
  • Patent number: D352400
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: November 15, 1994
    Assignee: Kabushiki Kaisha Kotobuki
    Inventor: Ryokichi Yamazaki
  • Patent number: D370791
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 18, 1996
    Assignee: Kabushiki Kaisha Kotobuki
    Inventor: Ryokichi Yamazaki
  • Patent number: D396967
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: August 18, 1998
    Assignee: Kotobuki Corporation
    Inventor: Ryokichi Yamazaki