Patents by Inventor Takao Maruyama

Takao Maruyama 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).

  • Publication number: 20050286371
    Abstract: A disk drive apparatus drives, by means of a motor, a disk mounted thereon so as to reproduce signals recorded in the disk. The disk drive apparatus has an edge detecting unit for generating an edge signal XEG indicating a timing of phase switching, in accordance with a plurality of signals CU, CV and CW induced when the motor is driven. The disk drive apparatus further has a drive voltage controlling unit for controlling, in accordance with the edge detection signal XEG, the maximum value of a drive voltage VS for driving said motor. This arrangement implements optimal motor control, while reducing circuit scale and cost and, at the same time, enhancing adaptability of the disk drive apparatus.
    Type: Application
    Filed: August 31, 2005
    Publication date: December 29, 2005
    Inventors: Seiryu Takayama, Ryo Ando, Takao Maruyama
  • Patent number: 6904331
    Abstract: The present invention is characterized in that in a simulation for predicting a steam pressure setpoint after grade change, an initial moisture percentage is evaluated from differences between bone-dry basis weights and between machine speeds before and after grade change; the bone-dry coated weight of a size is evaluated from the flow rate and concentration thereof; and then the dryer inlet moisture percentage of a web after a size press is calculated from the coated weight. Thus, the invention intends to improve the quality of products through precise dryer control, as well as reduce the time required for grade change, by precisely predicting the web's initial moisture percentage at the dryer inlet after grade change and precisely and quickly controlling dryer steam pressure during grade change.
    Type: Grant
    Filed: January 28, 2002
    Date of Patent: June 7, 2005
    Assignee: Yokogawa Electric Corporation
    Inventors: Takashi Sasaki, Kenichiro Yahiro, Takao Maruyama, Yoshitatsu Mori, Takahiro Ishizaki, Kenji Takao, Hirofumi Shimizu
  • Patent number: 6605185
    Abstract: A method and apparatus for manipulating dryer steam pressure in a paper machine during grade change, wherein change in moisture percentage is determined from a change in production amount during grade change, dryer stream pressure is manipulated so as to cancel the change in the moisture percentage, and production amount during grade change is calculated from basis weight and machine speed before and after grade change, whereby moisture percentage is kept constant during grade chagne so that sheet breaks are avoided and downtime is reduced.
    Type: Grant
    Filed: July 5, 2001
    Date of Patent: August 12, 2003
    Assignee: Yokogawa Electric Corporation
    Inventors: Takashi Sasaki, Takao Maruyama, Kenichiro Yahiro
  • Patent number: 6597140
    Abstract: A sensorless motor starting system of a simplified structure is capable of starting a sensorless spindle motor under optimal target starting conditions with low power consumption in accordance with the motor type and the kind of an optical disc to be driven, by executing manual fine adjustment of start parameters in response to any abnormal rotation caused at the start time. In this system, a rotation frequency signal is outputted from an edge detector on the basis of position signals in a start acceleration mode, and then is compared with a reference frequency signal by a comparator. And if the result of the decision therefrom signifies abnormal rotation, a switch is turned to its another terminal to select a manual setting mode. An operator performs manual fine adjustments of a phase switching time, a phase switching number and a drive voltage in order while monitoring phase switching control signals and position signals to thereby normalize the start state of the sensorless spindle motor.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: July 22, 2003
    Assignee: Sony Corporation
    Inventors: Seiryu Takayama, Takao Maruyama
  • Patent number: 6559504
    Abstract: To increase the withstand voltage and reduce ON-state resistance, a semiconductor device provided with a gate electrode formed on a semiconductor substrate via a gate insulating film, an LP layer (a P-type body region) formed so that the LP layer is adjacent to the gate electrode, an N-type source region and a channel region respectively formed in the LP layer, an N-type drain region formed in a position apart from the LP layer and an LN layer (a drift region) formed so that the LN layer surrounds the drain region is characterized in that the LP layer is formed up to the side of the drain region through an active region under the gate electrode and an SLN layer is formed from the drain region to a part before the active region.
    Type: Grant
    Filed: January 4, 2002
    Date of Patent: May 6, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Eiji Nishibe, Shuichi Kikuchi, Takao Maruyama
  • Patent number: 6547930
    Abstract: The present invention relates to improvement in a method for estimating a setting value of a dryer steam pressure after papermaking exchange according to simulation in a papermaking machine and an apparatus therefor, where a steam pressure setting value after papermaking exchange is estimated accurately by determining an in-hood air dry-bulb temperature on the basis of a difference between an in-drum steam temperature which has been just measured and an initial value of an in-drum steam temperature, thereby reducing a papermaking exchange time as well as reducing broke and improving the rate of operation.
    Type: Grant
    Filed: August 4, 2001
    Date of Patent: April 15, 2003
    Assignee: Yokogawa Electric Corporation
    Inventors: Takashi Sasaki, Takao Maruyama, Kenichiro Yahiro
  • Publication number: 20030007433
    Abstract: The present invention provides a disk driving apparatus which includes an interpolating edge circuit for generating an interpolating signal in accordance with a cycle of an edge detection signal, and a phase switching unit for performing phase switching by both the timing signal and the interpolating signal when a period for which the edge detection signal is normally generated reaches a predetermined value.
    Type: Application
    Filed: July 8, 2002
    Publication date: January 9, 2003
    Inventors: Seiryu Takayama, Takao Maruyama, Ryo Ando
  • Publication number: 20020198621
    Abstract: The present invention is characterized in that in a simulation for predicting a steam pressure setpoint after grade change, an initial moisture percentage is evaluated from differences between bone-dry basis weights and between machine speeds before and after grade change; the bone-dry coated weight of a size is evaluated from the flow rate and concentration thereof; and then the dryer inlet moisture percentage of a web after a size press is calculated from the coated weight. Thus, the invention intends to improve the quality of products through precise dryer control, as well as reduce the time required for grade change, by precisely predicting the web's initial moisture percentage at the dryer inlet after grade change and precisely and quickly controlling dryer steam pressure during grade change.
    Type: Application
    Filed: January 28, 2002
    Publication date: December 26, 2002
    Inventors: Takashi Sasaki, Kenichiro Yahiro, Takao Maruyama, Yoshitatsu Mori, Takahiro Ishizaki, Kenji Takao, Hirofumi Shimizu
  • Publication number: 20020186631
    Abstract: A disk drive apparatus drives, by means of a motor, a disk mounted thereon so as to reproduce signals recorded in the disk. The disk drive apparatus has an edge detecting unit for generating an edge signal XEG indicating a timing of phase switching, in accordance with a plurality of signals CU, CV and CW induced when the motor is driven. The disk drive apparatus further has a drive voltage controlling unit for controlling, in accordance with the edge detection signal XEG, the maximum value of a drive voltage VS for driving said motor. This arrangement implements optimal motor control, while reducing circuit scale and cost and, at the same time, enhancing adaptability of the disk drive apparatus.
    Type: Application
    Filed: May 16, 2002
    Publication date: December 12, 2002
    Inventors: Seiryu Takayama, Ryo Ando, Takao Maruyama
  • Publication number: 20020124982
    Abstract: The present invention relates to improvement in a method for estimating a setting value of a dryer steam pressure after papermaking exchange according to simulation in a papermaking machine and an apparatus therefor, where a steam pressure setting value after papermaking exchange is estimated accurately by determining an in-hood air dry-bulb temperature on the basis of a difference between an in-drum steam temperature which has been just measured and an initial value of an in-drum steam temperature, thereby reducing a papermaking exchange time as well as reducing broke and improving the rate of operation.
    Type: Application
    Filed: August 4, 2001
    Publication date: September 12, 2002
    Inventors: Takashi Sasaki, Takao Maruyama, Kenichiro Yahiro
  • Publication number: 20020104636
    Abstract: The present invention provides a method of manipulating dryer steam pressure in a paper machine during grade change. In the method, a change in the moisture percentage is determined from a change in the production mount during grade change, dryer steam pressure is manipulated so as to cancel the change in the moisture percentage, and the production amount in the course of grade change is calculated from basis weight and machine speed before and after the grade change.
    Type: Application
    Filed: July 5, 2001
    Publication date: August 8, 2002
    Inventors: Takashi Sasaki, Takao Maruyama, Kenichiro Yahiro
  • Publication number: 20020106860
    Abstract: To increase the withstand voltage and reduce ON-state resistance, a semiconductor device provided with a gate electrode formed on a semiconductor substrate via a gate insulating film, an LP layer (a P-type body region) formed so that the LP layer is adjacent to the gate electrode, an N-type source region and a channel region respectively formed in the LP layer, an N-type drain region formed in a position apart from the LP layer and an LN layer (a drift region) formed so that the LN layer surrounds the drain region is characterized in that the LP layer is formed up to the side of the drain region through an active region under the gate electrode and an SLN layer is formed from the drain region to a part before the active region.
    Type: Application
    Filed: January 4, 2002
    Publication date: August 8, 2002
    Applicant: Sanyo Electric Co., Ltd., a Japan corporation
    Inventors: Eiji Nishibe, Shuichi Kikuchi, Takao Maruyama
  • Patent number: 6399468
    Abstract: To increase the withstand voltage and reduce ON-state resistance, a semiconductor device provided with a gate electrode formed on a semiconductor substrate via a gate insulating film, an LP layer (a P-type body region) formed so that the LP layer is adjacent to the gate electrode, an N-type source region and a channel region respectively formed in the LP layer, an N-type drain region formed in a position apart from the LP layer and an LN layer (a drift region) formed so that the LN layer surrounds the drain region is characterized in that the LP layer is formed up to the side of the drain region through an active region under the gate electrode and an SLN layer is formed from the drain region to a part before the active region.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: June 4, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Eiji Nishibe, Shuichi Kikuchi, Takao Maruyama
  • Publication number: 20020003412
    Abstract: A sensorless motor starting system of a simplified structure is capable of starting a sensorless spindle motor under optimal target starting conditions with low power consumption in accordance with the motor type and the kind of an optical disc to be driven, by executing manual fine adjustment of start parameters in response to any abnormal rotation caused at the start time. In this system, a rotation frequency signal is outputted from an edge detector on the basis of position signals in a start acceleration mode, and then is compared with a reference frequency signal by a comparator. And if the result of the decision therefrom signifies abnormal rotation, a switch is turned to its another terminal to select a manual setting mode. An operator performs manual fine adjustments of a phase switching time, a phase switching number and a drive voltage in order while monitoring phase switching control signals and position signals to thereby normalize the start state of the sensorless spindle motor.
    Type: Application
    Filed: July 9, 2001
    Publication date: January 10, 2002
    Inventors: Seiryu Takayama, Takao Maruyama
  • Publication number: 20010031533
    Abstract: To increase the withstand voltage and reduce ON-state resistance, a semiconductor device provided with a gate electrode formed on a semiconductor substrate via a gate insulating film, an LP layer (a P-type body region) formed so that the LP layer is adjacent to the gate electrode, an N-type source region and a channel region respectively formed in the LP layer, an N-type drain region formed in a position apart from the LP layer and an LN layer (a drift region) formed so that the LN layer surrounds the drain region is characterized in that the LP layer is formed up to the side of the drain region through an active region under the gate electrode and an SLN layer is formed from the drain region to a part before the active region.
    Type: Application
    Filed: February 20, 2001
    Publication date: October 18, 2001
    Inventors: Eiji Nishibe, Shuichi Kikuchi, Takao Maruyama
  • Patent number: 5555147
    Abstract: In a combined thin film magnetic head comprising reading and recording parts which are formed on a main surface of a non-magnetic substrate for magnetically reading and recording information on a magnetic recording medium, the reading part comprises an under shield pattern, an upper shield pattern, and a magneto-resistive element formed between the under and the upper shield patterns. The under and the upper shield patterns have restricted areas which are much smaller than the main surface of the non-magnetic substrate. The recording part comprises a conductor member with a coil pattern. An outer periphery portion of the coil pattern is out of a forming area which is for forming the reading part.
    Type: Grant
    Filed: September 23, 1994
    Date of Patent: September 10, 1996
    Assignee: NEC Corporation
    Inventor: Takao Maruyama
  • Patent number: 5471349
    Abstract: A circuit for driving a dual-element magnetic head assembly made up of a magnetoresistive (MR) readback head and a recording head for recording and reproducing data out of a magnetic recording medium. When the head assembly ends a recording operation, the last recording magnetic field is oriented in a direction for deepening the bias to a MR element at all times. A bias electric field for the MR element is continuously applied even during recording operation. The circuit, therefore, stabilizes the bias to the MR element at the end of a recording operation, reduces noise during readback operation, and prevents the readback output from fluctuating every time a recording operation is performed.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: November 28, 1995
    Assignee: NEC Corporation
    Inventor: Takao Maruyama
  • Patent number: 5235484
    Abstract: In a magnetic transducer assembly for magnetic recording disks, a magnetic slider body has two laterally spaced apart longitudinal rails each having a floating surface and a groove formed between them. A thin-film magnetic core assembly is mounted on an end wall of each of the rails and a magnetic gap is formed on each floating surface. A suspension element has one end secured to the bottom surface of the groove for maintaining the slider assembly in a constant position with respect to the surface of the disk. Preferably, the longitudinal rails are bridged bya laterally extending block to create negative pressure between the rails by relative movement between the assembly and the surface of the disk, and the suspension element exerts pressure in a direction away from the surface of the disk.
    Type: Grant
    Filed: March 7, 1991
    Date of Patent: August 10, 1993
    Assignee: NEC Corporation
    Inventor: Takao Maruyama
  • Patent number: 5140484
    Abstract: A magnetoresistive playback head for a small magnetic disk. Electrodes connected to an MR element each has a linear portion extending over a length which is more than ten times greater than the width of the MR element. The electrodes each extends from the MR element at an angle less than 14 degrees. This allows only a single magnetic domain to exist in the MR element and frees the magneto-resistive response from distortions or hysteresis. As a result, signals reproduced from a magnetic recording medium do not include any distortion or noise.
    Type: Grant
    Filed: March 26, 1991
    Date of Patent: August 18, 1992
    Assignee: NEC Corporation
    Inventor: Takao Maruyama
  • Patent number: 4954920
    Abstract: A thin film magnetic head has a layer of soft magnetic material formed on a substrate. The layer is formed into two yoke pieces and a magnetic return path, which form a gap at ends of the yoke pieces. The opposite ends of the yoke pieces are joined to the magnetic return path by overlaying magneto-resistive pieces to which an electrical bias is applied.
    Type: Grant
    Filed: November 30, 1987
    Date of Patent: September 4, 1990
    Assignee: NEC Corporation
    Inventors: Kazuhiko Yamada, Takao Maruyama