Patents by Inventor Shigeki Niwa

Shigeki Niwa 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: 12053878
    Abstract: Provided is a sensing device to be applied to an actuator including a shaft that is movable in an axial direction, the shaft including a hollow part formed on at least a tip side of the shaft such that an interior of the shaft is hollow, the actuator being configured to generate a negative pressure in the hollow part to suction a workpiece to a tip of the shaft, thereby picking up the workpiece. The sensing device includes a flow sensor provided in a middle of an air passage to detect a flow rate of air flowing through the air passage, the air passage being a passage through which air sucked out from the hollow part flows when the negative pressure is applied to the hollow part, and a pressure sensor provided in a middle of the air passage, to detect a pressure in the air passage.
    Type: Grant
    Filed: August 1, 2019
    Date of Patent: August 6, 2024
    Assignee: THK CO., LTD.
    Inventors: Katsuya Fukushima, Masashi Ishii, Hiroki Niwa, Shigeki Hayashi, Akira Suzuki, Kazuto Oga, Shogo Wakuta, Satoshi Hara, Tomofumi Mizuno
  • Patent number: 12036666
    Abstract: The present invention reduces tact time for a pick-and-place operation by an actuator. In a housing of the actuator, an air passage being a passage of air when sucking air from a hollow part of a shaft is provided. Furthermore, a sucking valve that sucks air from the hollow part of the shaft through the air passage and a suction detecting sensor to detect that a workpiece is suctioned onto a tip of the shaft are provided in the air passage. Then, in the housing, the air passage is disposed at a position on a side opposite to a linear motion motor that moves the shaft in an axial direction of the shaft, via the shaft.
    Type: Grant
    Filed: August 1, 2019
    Date of Patent: July 16, 2024
    Assignee: THK CO., LTD.
    Inventors: Katsuya Fukushima, Masashi Ishii, Hiroki Niwa, Shigeki Hayashi, Akira Suzuki, Kazuto Oga, Shogo Wakuta, Satoshi Hara, Tomofumi Mizuno, Satoru Nagai
  • Patent number: 6187463
    Abstract: The present invention has been achieved by a material for a sintering appliance which comprises a base material comprising alumina×silica containing from 65 to 95% by weight of Al2O3 having formed on the surface thereof a flame-coated film comprising ZrO2 and CaO as main components, wherein the content of CaO is from 23 to 30% by weight based on the weight of the ZrO2 and CaO, the mineral composition of the main components of the coated film is calcium zirconate. Preferably the difference of thermal expansion between the base material and the flame-coated film is 0.3% or more at 1,200° C.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: February 13, 2001
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Tadashi Kimura, Hiroshi Okada, Toshiyuki Suzuki
  • Patent number: 6001470
    Abstract: A calcining tool material, comprising a flame-spray zirconia coating layer made of unstabilized zirconia and stabilized or partially-stabilized zirconia in admixture, formed on the surface of an alumina-silica-based substrate having an Al.sub.2 O.sub.3 content of not less than 65% by weight.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: December 14, 1999
    Assignee: Toshiba Ceramics Co., Ltd,
    Inventors: Shigeki Niwa, Tadashi Kimura, Hiroshi Okada, Toshiyuki Suzuki, Kenithi Urathuji, Ataru Nishikawa, Mamoru Uemura
  • Patent number: 5972529
    Abstract: The present invention has been achieved by a material for a sintering appliance which comprises a base material comprising alumina.times.silica containing from 65 to 95% by weight of Al.sub.2 O.sub.3 having formed on the surface thereof a flame-coated film comprising ZrO.sub.2 and CaO as main components, wherein the content of CaO is from 23 to 30% by weight based on the weight of the ZrO.sub.2 and CaO, the mineral composition of the main components of the coated film is calcium zirconate. Preferably the difference of thermal expansion between the base material and the flame-coated film is 0.3 or more at 1,200.degree. C.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: October 26, 1999
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Tadashi Kimura, Hiroshi Okada, Toshiyuki Suzuki
  • Patent number: 5958279
    Abstract: A refractory slide-gate plate including a refractory base plate which is designed in a ring shape or so as to have a recess portion on a surface thereof, a refractory plate member which is fixedly engaged with the inside of the ring-shaped refractory base plate or with the recess portion of the refractory slide-gate to be integrated with the refractory base plate, and an inert gas supply groove comprising a step portion which is formed in 2 to 20 mm width and in 2 to 20 depth on at least one of the inner peripheral portion of the ring-shaped refractory base plate and the inner peripheral portion of the recess portion. The refractory plate member is preferably formed of Al.sub.2 O.sub.3 --ZrO.sub.2 --C-based refractory material or ZrO.sub.2 -based refractory material.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: September 28, 1999
    Assignee: Toshiba Ceramics Co., Ltd
    Inventors: Toshio Kawamura, Kazuhide Kawai, Shigeki Niwa
  • Patent number: 5804324
    Abstract: A setting member for a heating material formed by sintering and heating a base and a coating layer at 1300.degree. to 1550.degree. C., in which the base comprises at least one selected from the group consisting of Al.sub.2 O.sub.3, MgO and ZrO.sub.2 in an amount of 70 wt % or more, the coating layer contains at least one main component selected from the group consisting of Al.sub.2 O.sub.3, MgO and ZrO.sub.2 in an amount of 80 wt % or more and 0.5 to 10.0 wt % of at least one additional component selected from Fe.sub.2 O.sub.3, TiO.sub.2, BaO, SrO, ZrO.sub.2, CaO, and MgO (different from CaO and MgO used as a stabilizer for ZrO.sub.2) excluding the same types of the additional component as used in the main component of the coating layer.
    Type: Grant
    Filed: January 18, 1996
    Date of Patent: September 8, 1998
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Hiroshi Okada, Yasuharu Okiyama, Toshiyuki Suzuki
  • Patent number: 5730892
    Abstract: The present invention provides a recycle slide gate plate, said slide gate plate being connected to a lower portion of a molten metal container and used for sliding a plate to control a flow of molten metal drained from the molten metal container, comprising an upper plate and/or a lower plate obtained by polishing a sliding surface of a slide gate plate used at least one time, at a predetermined smoothness tolerance, a tubular ring fixed to a through hole obtained by cutting out a molten metal outlet portion of the upper plate and/or the lower plate having a projecting portion on a side opposite to a sliding surface of the upper plate and/or the lower plate, said projecting portion having a total height of a sum of a height dimension substantially equal to a height of a projecting portion of a new plate before use and a thickness dimension to be reduced by polishing out the sliding surface, the projecting portion being provided with a molten metal outlet hole formed inside the projecting portion, and a cushi
    Type: Grant
    Filed: December 24, 1996
    Date of Patent: March 24, 1998
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Etsuhiro Hasebe, Kazuo Itoh, Toshihiro Indoh, Kohji Saitoh, Tamotsu Wakita, Masahiko Uchita, Hiroshi Hikima
  • Patent number: 5556568
    Abstract: A slide gate plate serving as a molten metal flow-rate control member for use in a molten metal discharging device, comprising an assembly of at least one stationary plate having a nozzle hole therein and a slide plate having a nozzle hole therein, the plates being designed so that one of the plates is thicker than the other plate by 1.5 mm or more. With this construction, the slide gate plate is reusable by polishing the sliding face off a worn plate for reuse.
    Type: Grant
    Filed: April 12, 1995
    Date of Patent: September 17, 1996
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Etsuhiro Hasebe, Kazuo Itoh, Toshihiro Indoh, Masamichi Asai
  • Patent number: 5055433
    Abstract: An alumina-zirconia electrofusing material whose chemical composition consists of about 30-75 wt. % Al.sub.2 O.sub.3 and about 25-70 wt. % ZrO.sub.2 is provided in an amount of about 5-50 wt %, and this electrofusing material is mixed with other materials, and a resultant mixture is press-shaped and fired to produce a slide gate refractory. In order to further improve resistance to corrosion and spalling, particle diameters of the electrofusing material are continuously distributed in a range from about 0.1 mm to about 2.5 mm.
    Type: Grant
    Filed: June 1, 1989
    Date of Patent: October 8, 1991
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Kazuhide Kawai, Takahumi Nishibe, Toshio Kawamura