Patents by Inventor Tadashi Sakurai

Tadashi Sakurai 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: 4840847
    Abstract: A conjugate fiber obtained by melt spinning (A) a crystalline poly-.alpha.-olefin and (B) an ethylene copolymer containing from 40 to 95% by weight of an ethylene unit and from 5 to 60% by weight of at least one dialkylaminoalkylacrylamide comonomer unit represented by formula (I): ##STR1## wherein R.sub.1 represents a hydrogen atom or a methyl group; R.sub.2 and R.sub.3 each represents an alkyl group having from 1 to 4 carbon atoms; and n represents an integer of from 2 to 5, said ethylene copolymer having a melt index of from 10 to 1000 g/10 min as measured according to JIS K-6760, either by aligning the components (A) and (B) in parallel or by aligning the component (A) as a core and the component (B) as a sheath. The conjugated fiber is excellent in thermal adhesion, absorptivity by an acid aqueous solution, and dyeability and can easily be fabricated into a nonwoven fabric or nonwoven molding suited for various applications including separators of lead accumulators.
    Type: Grant
    Filed: May 2, 1988
    Date of Patent: June 20, 1989
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tadayuki Ohmae, Tadashi Sakurai, Kouichiro Asao
  • Patent number: 4840029
    Abstract: Several embodiments of exhaust systems including reflective valve means interposed between the engine exhaust ports and an expansion chamber for improving performance at mid range and under low speeds. The reflective means comprise a plurality of rotatably supported members that are affixed to different shafts and the shafts are coupled together for simultaneous rotation. In some embodiments, the shafts are coupled by a linkage system and in another by means of a gear system. The shafts are journaled in either the same or separate valve housings and the valve members may be positioned on different horizontal planes or at an angle to each other to suit a variety of exhaust pipe configurations.
    Type: Grant
    Filed: March 6, 1987
    Date of Patent: June 20, 1989
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Tadashi Sakurai, Wataru Fuchigami
  • Patent number: 4831095
    Abstract: A novel ethylene copolymer and a process for producing said copolymer are disclosed. This ethylene copolymer contains from 40 to 95% by weight of ethylene, from 60 to 5% by weight of at least one dialkylaminoalkyl acrylamide comonomer represented by formula (A): ##STR1## wherein the symbols are as defined in the appended claims, and 0 to 20% by weight of at least one ethylenically unsaturated comonomer, and has a number average molecular weight of from 5,000 to 50,000.
    Type: Grant
    Filed: January 19, 1988
    Date of Patent: May 16, 1989
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tadayuki Ohmae, Kentaro Mashita, Noboru Yamaguchi, Kouichiro Asao, Hisao Tanaka, Tadashi Sakurai
  • Patent number: 4816739
    Abstract: A first converter which includes a switching element operating on a comparatively lower threshold voltage and generating a first output voltage, a second converter which includes a switching element operating on a threshold voltage higher than that of the first conversion unit and generating a second output voltage higher than the first output voltage, and a level shift circuit which provides the switching signal for activating the switching element of the second converter in accordance with generation of the first output voltage.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: March 28, 1989
    Assignee: Motorola, Inc.
    Inventors: Tadashi Sakurai, Masahiro Kojima
  • Patent number: 4795420
    Abstract: An improved valve for use in an exhaust system to increase the performance of the engine throughout the entire engine and load speed ranges by providing reflective areas that cooperate with the individual exhaust pipes of the engine to reduce pressure pulses in the combustion chamber during valve overlap periods. A number of embodiments of compact valve constructions are shown that employ relatively short journaling shafts for minimizing the effects of thermal expansion.
    Type: Grant
    Filed: March 6, 1987
    Date of Patent: January 3, 1989
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Tadashi Sakurai, Wataru Fuchigami, Hideaki Kitta
  • Patent number: 4765137
    Abstract: Several embodiments of exhaust systems for motorcycles that improve the engine performance by positioning reflective valve members between an expansion chamber and the exhaust ports of the engine. In each embodiment, there are provided separate valve bodies with separate valve supporting shafts that are all controlled by means of a common controller either through a single or multiple servo motors.
    Type: Grant
    Filed: March 6, 1987
    Date of Patent: August 23, 1988
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Tadashi Sakurai, Wataru Fuchigami
  • Patent number: 4499432
    Abstract: An operational power amplifier having a bootstrap power output stage is designed to provide maximum dynamic range over a wide range of supply voltages. A control circuit in the form of a switched current mirror is added to the amplifier biasing circuit. At supply voltage higher than a predetermined threshold, the amplifier bias is adjusted to provide one half of this voltage at the output terminal. For supply voltages less than the threshold value, the output voltage is made less than half supply voltage.
    Type: Grant
    Filed: November 4, 1982
    Date of Patent: February 12, 1985
    Assignee: National Semiconductor Corporation
    Inventors: William H. Gross, Tadashi Sakurai
  • Patent number: 4466127
    Abstract: A radio receiver having a counter which generates a count value corresponding to the frequency of a station to be received which value is stored in a memory through a load enable signal produced when a ramp voltage reaches a value corresponding to a comparison voltage set to correspond to the frequency. The stored count value controls a programmable divider of a phase lock loop circuit to cause the oscillator of the circuit to produce the correct local oscillator frequency to be received. An N-nary counter permits only every Nth count value to be stored in the memory to correspond to the frequency spacing between stations.
    Type: Grant
    Filed: May 16, 1979
    Date of Patent: August 14, 1984
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsutomu Ohgishi, Tadashi Sakurai
  • Patent number: 4352204
    Abstract: The reference signal output from a reference oscillator is applied to a counter where the reference signal is counted to provide a count output as a changeable digital value. A saw-tooth wave generator is provided so as to generate a saw-tooth wave such that the saw-tooth wave is changeable of the waveform in synchronism with the count output. A comparison voltage generator is also provided which may typically comprise a variable resistor. A load enable signal generator is provided to receive the saw-tooth wave output from the saw-tooth wave generator and the comparison voltage output as set in the comparison voltage generator. The load enable signal generator is structured to compare the saw-tooth wave output and the comparison voltage output to provide a load enable signal whenever both outputs coincide with each other.
    Type: Grant
    Filed: September 27, 1979
    Date of Patent: September 28, 1982
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsutomu Ohgishi, Tadashi Sakurai
  • Patent number: 4236251
    Abstract: A digital frequency synthesizer radio receiver, comprising a scan memory for storing a digital value data concerning a broadcasting frequency; a digital value data entry device for selectively entering a digital value concerning a broadcasting frequency; a preset memory having a plurality of storing locations, each adapted for storing a digital value concerning a specified broadcasting frequency, a channel selector coupled to said preset memory for selecting one of said storing locations thereof, said preset memory being responsive to said channel selector and said digital value data entry device for loading the entered digital value data in the location of the preset memory selected by the channel selector; and a phase locked loop selectively and operatively coupled to either of said scan memory and said preset memory for providing an oscillation frequency signal the frequency of which is associated with the digital value data loaded in the selected one of said scan memory and the preset memory.
    Type: Grant
    Filed: September 29, 1977
    Date of Patent: November 25, 1980
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsutomu Ohgishi, Toru Akiyama, Tadashi Sakurai
  • Patent number: 4201945
    Abstract: A lock detecting circuit of a phase locked loop, comprising a phase comparator for receiving a reference frequency signal and a signal being compared with the reference frequency signal, a charging/discharging circuit which is charge/discharge controlled responsive to the output of the phase comparator and either of the above described two signals, and a delay flip-flop responsive to the output of the charging/discharging circuit and in synchronism with the signal applied to the charging/discharging circuit for assuming one storing state for providing an output representative of the phase difference between the above described two signals.
    Type: Grant
    Filed: May 8, 1978
    Date of Patent: May 6, 1980
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsutomu Ohgishi, Toru Akiyama, Tadashi Sakurai
  • Patent number: 4179628
    Abstract: A flip-flop having a reset preferential function, comprising a set input terminal, a reset input terminal, a clock signal source operatively coupled through a field effect transistor to the set input terminal, a capacitance formed at the gate electrode of the field effect transistor, a charge control transistor controllable responsive to the clock signal for precharging the capacitance prior to the clock signal, a discharge control transistor controllable responsive to the reset signal for discharging the capacitance, whereby the capacitance is precharged prior to the clock signal and is discharged responsive to the reset signal, the field effect transistor being rendered conductive as a function of the electric charge of the capacitance, the clock signal source being operatively coupled to the set input terminal as a function of the conduction state of the field effect transistor, whereby the flip-flop is set responsive to the leading edge of the clock signal and is reset responsive to the reset signal in pr
    Type: Grant
    Filed: November 21, 1977
    Date of Patent: December 18, 1979
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsutomu Ohgishi, Toru Akiyama, Tadashi Sakurai