Patents Assigned to Yamauchi Corporation
  • Publication number: 20080021134
    Abstract: A hot-press cushion material is a complex comprising paper formed of a fiber material and a rubber impregnated in the paper, and the volume ratio between the fiber material and the rubber is within a range of 1/1.5 to 1/7.5, and the void ratio in the complex is within a range of 60 to 90%.
    Type: Application
    Filed: July 18, 2007
    Publication date: January 24, 2008
    Applicant: Yamauchi Corporation
    Inventor: Akira Yoshida
  • Patent number: 7243359
    Abstract: A disk device (10) comprises a case (11) for supporting the entire disk device (10), a base chassis (12) on which a spindle motor (21) for rotating the disk is set, a counterweight (13) for absorbing vibration of the base chassis (12), and a plurality of elastic bodies (14a-14d) for mutually supporting the case (11), the base chassis (12) and the counterweight (13). The case (11), the base chassis (12), and the counterweight (13) are supported by the common elastic bodies (14a-14d). As a result, there can be provided the dynamic vibration absorber in which the number of parts is not increased and a cost can be reduced, and the optical disk device (10) using the dynamic vibration absorber.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: July 10, 2007
    Assignee: Yamauchi Corporation
    Inventors: Toshio Saito, Hiroshi Ohyama
  • Patent number: 7163202
    Abstract: A sheet feeding device comprises a sheet feeding member having an outer layer thereof, a sheet loaded on a sheet loading member being depressed on a peripheral surface of the outer layer, the sheet feeding member delivering the sheet depressed to the peripheral surface, through rotation of the peripheral surface. An inclination member having a depression portion and an inclined surface, the depression portion depressing the sheet on the peripheral surface, and a leading edge of the sheet being brought in contact with the inclined surface. The outer layer of the sheet feeding member is formed of a cross-linked rubber material which has a JIS-A hardness in a range between 25 degrees and 40 degrees, a tearing strength measured with a JIS B-type specimen, which is 10 N/mm or more, and a viscoelastic characteristic expressed by a loss tangent, which is 0.045 or less.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: January 16, 2007
    Assignees: Ricoh Company, Ltd., Yamauchi Corporation
    Inventors: Toshifumi Togashi, Eiichi Hattori
  • Patent number: 7135137
    Abstract: A basic manufacturing method of a resin roll includes a procedure in which a synthetic resin outer cylinder (1) molded in the shape of a cylinder is arranged so as to cover an outer surface of a metal core (2), a clearance formed between metal core (2) and outer cylinder 1 is filled with a thermoset adhesive (3), and adhesive (3) is hardened to integrate the constituents into one piece through bonding. The manufacturing method of a resin roll has a feature in that integration of the constituents into one piece through bonding is performed by first hardening of the adhesive in a state where outer cylinder (1) is held at a first temperature and adhesive (3) is thereafter heated at a second temperature higher than the first temperature for second hardening.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: November 14, 2006
    Assignee: Yamauchi Corporation
    Inventors: Kenjiro Nakayama, Atsuo Watanabe, Tetsuya Murakami
  • Patent number: 7097741
    Abstract: A shoe press belt capable of preventing the occurrence and growth of cracks therein and is used in a paper-making press apparatus containing a press roll, a belt, and a pressure shoe for pressing a material web, wherein the shoe press belt includes a reinforcing layer, a first elastic material layer, and a second elastic material layer. A plurality of grooves are formed at an exterior peripheral surface region of the first elastic material layer. The bottom of the grooves at an axial end region of the belt corresponding to at least one of an end-proximate region in an axial direction of the pressure shoe and an end-proximate region in an axial direction of the press roll extends toward the reinforcing layer relative to the bottom of the grooves at a region other than the end region.
    Type: Grant
    Filed: April 8, 2002
    Date of Patent: August 29, 2006
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Watanabe, Takahisa Hikida, Atsushi Watanabe
  • Patent number: 7090747
    Abstract: A papermaking belt which prevents cracking and inhibits crack growth which includes a reinforcing substrate embedded in a thermosetting polyurethane layer so that the reinforcing substrate and the thermosetting polyurethane layer are integrated with each other and the outer peripheral surface and the inner peripheral surface of the belt are formed by polyurethane layers, the polyurethane layer forming the outer peripheral surface being made of a composition containing a urethane prepolymer having isocyanate groups on its ends and a hardener containing dimethylthiotoluenediamine.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: August 15, 2006
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Watanabe, Takahisa Hikida, Atsushi Watanabe
  • Patent number: 7028946
    Abstract: An expander roll that has a plurality of metallic, cylindrical roll members is constructed to obtain sufficient liquidtightness, wherein a gap-facing concave portion 19 is formed in the outer circumferential surface of a ring-shaped elastic packing 17 with which a gap 18 between adjoining, cylindrical roll members 6A and 6B is closed, in addition, a required number of concave portions 21 are formed in both side parts of the gap-facing concave portion 19 so as to form pleat-like portions 22 and the outer circumferential surface of the pleat-like portion 22 is fixed to the inner circumferential surfaces of the cylindrical roll members 6A and 6B on the same side as the side of the outer circumferential surface of the pleat-like portion 22.
    Type: Grant
    Filed: December 2, 2003
    Date of Patent: April 18, 2006
    Assignee: Yamauchi Corporation
    Inventors: Kazuhiro Katsuhara, Yoshinobu Nakamura, Isao Origuchi
  • Publication number: 20060005392
    Abstract: A method of manufacturing an elastic sleeve for a shoe press having an inner diameter gradually reduced from both ends toward a center in an axial direction, comprising the steps of stretching the sleeve formed of an uncured or imperfectly cured elastic material between two rolls, moving the two rolls in directions apart from each other while deflecting the two rolls in such directions that the center parts thereof are moved close to each other by utilizing the tension of the sleeve, and perfectly curing, in this state, the elastic material while rotating the sleeve to gradually reduce the inner diameter of the elastic sleeve from both ends toward the center in the axial direction.
    Type: Application
    Filed: August 25, 2003
    Publication date: January 12, 2006
    Applicant: Yamauchi Corporation
    Inventor: Takahisa Hikida
  • Patent number: 6983540
    Abstract: A liquid mixture containing a liquid polymeric material and a granular filler is injected into a mold (11) for centrifugal molding and subjected to centrifugal molding, thereby preparing a cylindrical body including a homogeneous dispersion layer (2) having the filler homogeneously dispersed in the polymeric material and a high-density packed bed (1), formed on the outer peripheral surface side or on the inner peripheral surface side of the homogeneous dispersion layer (2), containing the aforementioned polymeric material more densely filled with the aforementioned filler. The high-density packed bed (1) is removed for exposing the surface of the homogeneous dispersion layer (2). According to this structure, the yield of the elastic cylindrical body can be improved.
    Type: Grant
    Filed: August 13, 2001
    Date of Patent: January 10, 2006
    Assignee: Yamauchi Corporation
    Inventors: Shunsuke Kato, Mitsuru Tsunokawa, Atsuo Tanaka
  • Patent number: 6921461
    Abstract: A papermaking belt of improved durability capable of preventing a crack from progressing into the which includes a reinforcing substrate embedded in an elastic material, and the elastic material containing a surface layer, a back layer and an intermediate layer located between the surface layer and the back layer and having a thick part containing a thickness in the belt thickness direction along the belt traveling direction in the said intermediate layer. The thick part can also be exposed on the belt surface through the surface layer, the thick part is preferably made of a low-hardness elastic material and the surface layer is preferably made of a high-hardness elastic material.
    Type: Grant
    Filed: November 22, 2001
    Date of Patent: July 26, 2005
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Watanabe, Takahisa Hikida, Atsushi Watanabe
  • Patent number: 6769642
    Abstract: A pinch roller which includes a cylindrical elastic body formed of a polymer blend including acrylonitrile butadiene copolymer rubber (NBR), and at least one of a highly saturated copolymer rubber containing nitrile group obtained by hydrogenating a butadiene part of said acrylonitrile-butadiene copolymer rubber, and ethylene-&agr;-olefin type copolymer rubber, and a resin sleeve press-fitted in the elastic body. The elongation of the elastic body is set to be at least 5% and not more than 15%. A pinch roller apparatus includes this pinch roller.
    Type: Grant
    Filed: April 5, 2002
    Date of Patent: August 3, 2004
    Assignee: Yamauchi Corporation
    Inventors: Hiroyuki Yamasaki, Hitoshi Hamada, Atsushi Kato
  • Publication number: 20040110616
    Abstract: An expander roll that has a plurality of metallic, cylindrical roll members is constructed to obtain sufficient liquidtightness, wherein a gap-facing concave portion 19 is formed in the outer circumferential surface of a ring-shaped elastic packing 17 with which a gap 18 between adjoining, cylindrical roll members 6A and 6B is closed, in addition, a required number of concave portions 21 are formed in both side parts of the gap-facing concave portion 19 so as to form pleat-like portions 22 and the outer circumferential surface of the pleat-like portion 22 is fixed to the inner circumferential surfaces of the cylindrical roll members 6A and 6B on the same side as the side of the outer circumferential surface of the pleat-like portion 22.
    Type: Application
    Filed: December 2, 2003
    Publication date: June 10, 2004
    Applicant: YAMAUCHI CORPORATION
    Inventors: Kazuhiro Katsuhara, Yoshinobu Nakamura, Isao Origuchi
  • Patent number: 6514888
    Abstract: A cushioning material for forming press includes fiber material layers 31 and 32 superimposed with a bonding material layer 30 interposed, an upper rubber layer 33 positioned on an upper surface of one fiber material layer 31, a lower rubber layer 34 positioned on a lower surface of the other fiber material layer 32, an upper exudation preventing layer 35 positioned on an upper surface of the upper rubber layer 33, and a lower exudation preventing layer 36 positioned on a lower surface of the lower rubber layer 34.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: February 4, 2003
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Tanaka, Akira Yoshida
  • Patent number: 6489402
    Abstract: A rubber vibration insulator for use in a vibration insulation device integrated into precision instruments such as acoustic, computer-associated and game instruments, which insulator has a low hardness, a small compression set, a large loss tangent and a small temperature dependence and can be prepared by curing a rubber composition comprising 100 parts by weight of a partially crosslinked butyl rubber and 50 to 200 parts by weight of an extender component as well as a vulcanizing agent.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: December 3, 2002
    Assignee: Yamauchi Corporation
    Inventors: Hiroshi Ohyama, Ryo Ogawa, Hiroyuki Maruko, Hiroshi Kuramochi
  • Publication number: 20020079053
    Abstract: A method is provided for manufacturing a laminate with cushioning material for forming press made with fiber material layers 31 and 32 superimposed with a bonding material layer 30 interposed, an upper rubber layer 33 positioned on an upper surface of one fiber material layer 31, a lower rubber layer 34 positioned on a lower surface of the upper rubber layer 33, and a lower exudation preventing layer 36 positioned on a lower surface of the lower rubber layer 34.
    Type: Application
    Filed: October 29, 2001
    Publication date: June 27, 2002
    Applicant: Yamauchi Corporation
    Inventors: Atsuo Tanaka, Akira Yoshida
  • Patent number: 6391460
    Abstract: A rubber for a hot press cushioning pad having a value of loss tangent (tan &dgr;) in accordance with dynamic viscoelasticity measurement of at most 0.04, wherein the temperature condition is set at a hot press temperature ranging from 150° C. to 300° C., and the frequency condition is set to a time period of one press cycle ranging from 1 to 2×104 seconds.
    Type: Grant
    Filed: August 5, 1999
    Date of Patent: May 21, 2002
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Tanaka, Akira Yoshida
  • Patent number: 6337112
    Abstract: An endless belt in which a fibrous material is dispersed in a substantially uniform manner all over an endless elastic body layer is provided. A non-woven tape is impregnated with a polyurethane elastomer material liquid and wound and layered on a supporting belt, and then, after curing the polyurethane elastomer material liquid to form an elastic body, it is removed from supporting belt.
    Type: Grant
    Filed: April 1, 1994
    Date of Patent: January 8, 2002
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Watanabe, Kenjiro Nakayama, Takahisa Hikida
  • Patent number: 6319624
    Abstract: In the resin roll 5 for calendering a magnetic recording medium, a surface portion 3a of a thermosetting resin outer layer 3 has high storage elastic modulus (E′) of 5×1010 to 5×1011 dyn/cm2 at a temperature of 50° to 150° C. at a frequency of 10 hertz (Hz). At the surface portion of the thermosetting resin outer layer, the expression representing the relation between storage elastic modulus (E′) and the Poisson's ratio (&ngr;) is within the following range, under the same conditions: 2×10−12 cm2/dyn<(1−&ngr;2)/E′<2×10−11 cm2/dyn.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: November 20, 2001
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Watanabe, Kenjiro Nakayama, Tatsuyuki Abe
  • Patent number: 6030328
    Abstract: In a resin roll 5 for calendering a magnetic recording medium, a surface portion 3a of a thermosetting resin outer layer 3 has high storage elastic modulus (E') of 5.times.10.sup.10 to 5.times.10.sup.11 dyn/cm.sup.2 at a temperature of 50 to 150.degree. C. at a frequency of 10 hertz (Hz). At the surface portion of the thermosetting resin outer layer, the expression representing the relation between storage elastic modulus (E') and the Poisson's ratio (.nu.) is within the following range, under the same conditions:2.times.10.sup.-12 cm.sup.2 /dyn<(1-.nu..sup.2)/E'<2.times.10.sup.-11 cm.sup.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: February 29, 2000
    Assignee: Yamauchi Corporation
    Inventors: Atsuo Watanabe, Kenjiro Nakayama, Tatsuyuki Abe
  • Patent number: 5934538
    Abstract: A pinch roller apparatus fully satisfying tape running stability and bearing durability is disclosed. A roller shaft is arranged inclined such that its tip end is closer to a capstan. A plain bearing is formed of resin having a Young's modulus of 10 kgf/mm.sup.2 to 1500 kgf/mm.sup.2. Self alignment of the pinch roller is realized by elastic deformation of the plain bearing.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: August 10, 1999
    Assignees: Yamauchi Corporation, Oiles Corporation
    Inventors: Mitsuaki Hirose, Hiroyuki Yamazaki, Yukiharu Uemura