Patents by Inventor Akihiro Asada
Akihiro Asada 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: 7575081Abstract: A work vehicle includes a traveling vehicle body and a hood provided at a front portion of the vehicle body for covering an engine room. The hood includes a front face having a plurality of first air vent holes and right and left side faces each having a plurality of second air vent holes. A radiator is mounted inside the hood, ambient air being drawn in through the first and second air vent holes toward the radiator. A vent hole area ratio of each side face of the hood determined by the second air vent holes is set smaller than a vent hole area ratio of the front face of the hood determined by the first air vent holes.Type: GrantFiled: September 17, 2004Date of Patent: August 18, 2009Assignee: Kubota CorporationInventors: Mitsuhiko Obe, Akihiro Asada, Takashi Kobayashi
-
Patent number: 7573797Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: GrantFiled: October 26, 2007Date of Patent: August 11, 2009Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Patent number: 7570564Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: GrantFiled: October 26, 2007Date of Patent: August 4, 2009Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Patent number: 7570565Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: GrantFiled: October 26, 2007Date of Patent: August 4, 2009Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Publication number: 20090073829Abstract: A hybrid LDD includes a read channel to selectively output a read current, a plurality of write channels, each to selectively output a different write current, and an oscillator channel to selectively output an oscillator current. Additionally, the hybrid LDD includes programmable LDD controller that receives the plurality of enable signals from the external controller, and based on the enable signals, controls timing of the currents output by at least the write channels. The programmable LDD controller can also control timing of the currents output by the read and oscillator channels, based on the enable signals. Further and alternative embodiments are also provided.Type: ApplicationFiled: November 25, 2008Publication date: March 19, 2009Applicant: Intersil Americas Inc.Inventors: Theodore D. Rees, Akihiro Asada, D. Stuart Smith
-
Patent number: 7499478Abstract: An optical disk apparatus uses a laser driver which can measure the frequency of the high-frequency superimposed current of the semiconductor laser simply and accurately. The apparatus includes a semiconductor laser which emits a laser beam onto the optical disk, a laser driver which drives the semiconductor laser with a current, with the high-frequency current being superimposed thereon, and measures the frequency of the high-frequency current, and a main controller which controls the frequency of the high-frequency current produced by the laser driver by using the frequency measured by the laser driver.Type: GrantFiled: September 9, 2004Date of Patent: March 3, 2009Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Makoto Nihei, Toshimitsu Kaku, Akihiro Asada, Takashi Hoshino
-
Patent number: 7492686Abstract: Embodiments of the present invention relate to systems and methods for providing flexible multipulse strategies. In specific embodiments, a plurality of multipulse location registers are dedicated to storing multipulse location information. Each of a plurality of different mark-lengths that can result in at least one multipulse is mapped to one or more bit location within the multipulse location registers, such that a unique multipulse execution strategy can be defined for each of the plurality of different mark-lengths. Each bit location within the multipulse location registers can contain a first type of bit or a second type of bit. The first type of bit is used to indicate where to execute a multipulse, and the second type of bit is used to indicate where to not execute a multipulse. This abstract is not intended to be a complete description of the various embodiments of the present invention.Type: GrantFiled: September 22, 2005Date of Patent: February 17, 2009Assignee: Intersil Americas Inc.Inventors: Miguel Gabino Perez, Alexander Fairgrieve, Akihiro Asada
-
Publication number: 20080068947Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: ApplicationFiled: October 26, 2007Publication date: March 20, 2008Applicants: HITACHI, LTD, HITACHI-LG DATA STORAGE, INC.Inventors: Akihiro ASADA, Masaaki KUREBAYASHI
-
Publication number: 20080056078Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: ApplicationFiled: October 26, 2007Publication date: March 6, 2008Applicants: HITACHI, LTD., HITACHI-LG DATA STORAGE, INC.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Publication number: 20080056090Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: ApplicationFiled: October 26, 2007Publication date: March 6, 2008Applicants: HITACHI, LTD., HITACHI-LG DATA STORAGE, INC.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Publication number: 20080008062Abstract: Provided herein are hybrid laser diode drivers (LDDs) that drive a laser diode in response to receiving enable signals from a controller. In accordance with specific embodiments, a hybrid LDD includes a read channel to selectively output a read current, one or more write channel each to selectively output a write current, and an oscillator channel to selectively output an oscillator current. Additionally, in specific embodiments the hybrid LDD includes a state machine that receives the enable signals from the controller, and based on the enable signals, controls timing of the currents output by the read, write and oscillator channels.Type: ApplicationFiled: May 16, 2007Publication date: January 10, 2008Applicant: INTERSIL AMERICAS INC.Inventors: Theodore D. Rees, Akihiro Asada
-
Publication number: 20080008066Abstract: Provided herein are hybrid laser diode drivers (LDDs) that drive a laser diode in response to receiving enable signals from a controller. In accordance with specific embodiments, a hybrid LDD includes a read channel to selectively output a read current, one or more write channel each to selectively output a write current, and an oscillator channel to selectively output an oscillator current. Additionally, in specific embodiments the hybrid LDD includes a decoder that receives the enable signals from the controller, and based on the enable signals, controls timing of the currents output by the read, write and oscillator channels.Type: ApplicationFiled: May 16, 2007Publication date: January 10, 2008Applicant: INTERSIL AMERICAS INC.Inventors: Theodore D. Rees, Akihiro Asada
-
Publication number: 20070266812Abstract: A speed changing structure for a work vehicle, comprising a travel speed changing device having a plurality of speed change positions, a manually operated speed changing lever (63), control means (64) for controlling the travel speed changing device, and a manually operable operating part (65) provided to the speed changing lever (63), wherein the control means (64) has a first speed changing mode for operating the travel speed changing device in single steps so as to follow the operation of the speed changing lever (63), and a second speed changing mode for operating the travel speed changing device without passing through intermediate speed change positions to a speed change position that corresponds to the operating position after the speed changing lever (63) has been moved from the speed change position that corresponds to the operating position prior to the speed changing lever (63) being operated; and the control means (64) operates the travel speed changing device in the first speed changing mode whenType: ApplicationFiled: March 21, 2007Publication date: November 22, 2007Applicant: Kubota CorporationInventor: Akihiro Asada
-
Patent number: 7298681Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: GrantFiled: February 23, 2006Date of Patent: November 20, 2007Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Publication number: 20060280089Abstract: Embodiments of the present invention relate to systems and methods for providing flexible multipulse strategies. In specific embodiments, a plurality of multipulse location registers are dedicated to storing multipulse location information. Each of a plurality of different mark-lengths that can result in at least one multipulse is mapped to one or more bit location within the multipulse location registers, such that a unique multipulse execution strategy can be defined for each of the plurality of different mark-lengths. Each bit location within the multipulse location registers can contain a first type of bit or a second type of bit. The first type of bit is used to indicate where to execute a multipulse, and the second type of bit is used to indicate where to not execute a multipulse. This abstract is not intended to be a complete description of the various embodiments of the present invention.Type: ApplicationFiled: September 22, 2005Publication date: December 14, 2006Applicant: Intersil Americas Inc.Inventors: Miguel Perez, Alexander Fairgrieve, Akihiro Asada
-
Publication number: 20060146679Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: ApplicationFiled: February 23, 2006Publication date: July 6, 2006Applicants: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Patent number: 7038989Abstract: An optical disk drive includes drive current generation unit for supplying a mark forming semiconductor laser drive current and a space forming semiconductor laser drive current; first high-frequency superimposition unit for superimposing a high-frequency component on the space forming semiconductor laser drive current; and high-frequency superimposition control unit for controlling the first high-frequency superimposition unit to stop the superimposition of the high-frequency component for a predetermined duration prior to a timing at which to switch from the space forming semiconductor laser drive current to the mark forming semiconductor laser drive current, eliminating positional variations on the disk of the mark leading and trailing edges due to the high frequency superimposition.Type: GrantFiled: October 28, 2002Date of Patent: May 2, 2006Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.Inventors: Akihiro Asada, Masaaki Kurebayashi
-
Patent number: 6954410Abstract: A laser waveform generation function is provided in a laser driving waveform generator 2 near a laser 3. A recording clock generator 9 is included in the laser driving waveform generator 2 to generate a clock with a frequency higher than that of a synchronizing clock 202. This allows a recording laser current (waveform) to be generated without transmission of a high frequency signal from the modulator 6. Further, because the synchronizing clock 202 is stopped upon a reproduction operation including reproduction operation in an ID unit, undesired effects on a reproduction operation such as ID reproduction can be reduced. Because the response speed of the recording clock generator 9 can be changed, a high precision clock can be generated. Thus, a high-precision recording laser current (waveform) can be generated.Type: GrantFiled: August 13, 2002Date of Patent: October 11, 2005Assignee: Hitachi, Ltd.Inventors: Takashi Hoshino, Toshimitsu Kaku, Akihiro Asada, Takehiko Sekine
-
Patent number: D527743Type: GrantFiled: August 27, 2004Date of Patent: September 5, 2006Assignee: Kubota CorporationInventors: Akihiro Asada, Junta Kuwae
-
Patent number: D538306Type: GrantFiled: August 27, 2004Date of Patent: March 13, 2007Assignee: Kubota CorporationInventors: Akihiro Asada, Junta Kuwae