Patents Assigned to Yamada Co., Ltd.
  • Patent number: 5715639
    Abstract: A metal roof board connecting structure for connecting metal roof boards includes a raised-up flat lock seam portion formed by bending flatly and seamly raised-up regions of two metal roof boards which are arranged adjacently to each other, and a cap member capped on the raised-up flat lock seam portion. A part of the raised-up region of one of the two metal roof boards forms a first cap engaging projection and a bent portion of the raised-up flat lock seam portion forms a second cap engaging projection so as to be arranged in symmetrical with the first projection. The cap member has a two elastic side walls a center portion of each of which has an engaging recess and a lower end portion of each of which is extended downwardly and outwardly to extend away from each other.
    Type: Grant
    Filed: September 6, 1995
    Date of Patent: February 10, 1998
    Assignee: Yamada Co., Ltd.
    Inventor: Yukio Yamada
  • Patent number: 4935977
    Abstract: A leaf spring includes a plate having a thickness of between approximately 5 mm and 20 mm, a width of between approximately 20 mm and 200 mm, and a given length. The plate is arcuately deformed so that it includes a central portion with a height of between 20 mm and 40 mm. The plate exhibits a predetermined resiliency for maintaining the plate in a substantially horizontal position under a load of between 5 kg and 30 kg and for preventing the plate from breaking under a load of between 50 kg and 100 kg. Further, the plate includes first and second layers made of glass-fiber or carbon-fiber and a core member made of a polyurethane foam material positioned between the first and second layers.
    Type: Grant
    Filed: June 12, 1988
    Date of Patent: June 26, 1990
    Assignee: Yamada Co., Ltd.
    Inventor: Junji Yamada
  • Patent number: 4384379
    Abstract: An expansion bed which is easily expansible and contractible along its longitudinal direction. The bed comprises a frame having at least two support links on each side which connect front and rear upstanding frame plates. Each of the pairs of support links comprises a support leg which adjustably connects the front and rear frame plates. A plurality of arms are connected to the upper end of the support links and a plurality of mounting plates are positioned upon the support arms for receiving a mattress or other bed surface. The frame plates can be provided with rollers for facilitating movement of the bed and a stopper can be provided for preventing movement of the rollers. If desired, the mounting plates can be placed upon rather than connected to the arms and can be formed so that the widths of adjacent pairs of the plates increase in the longitudinal direction of the bed.
    Type: Grant
    Filed: June 19, 1980
    Date of Patent: May 24, 1983
    Assignee: Yamada Co., Ltd.
    Inventor: Junji Yamada
  • Patent number: 4276666
    Abstract: A mattress is composed of a sponge like material which compresses by 65% of the thickness thereof under a load of 30 Kg per 314 cm.sup.2. The mattress is treated so that it subsequently is compressed by 65% of the thickness thereof under a load of 25 Kg per 314 cm.sup.2. The treatment consists of providing the upper surface of the mattress with a plurality of protuberances. The mattress may be composed of several layers of such material, each having such a plurality of protuberances on one surface. The mattress may be encased by elastic netting.
    Type: Grant
    Filed: August 20, 1979
    Date of Patent: July 7, 1981
    Assignee: Yamada Co., Ltd.
    Inventor: Junji Yamada