Patents by Inventor Akimasa Ishikawa
Akimasa Ishikawa 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).
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Patent number: 10133218Abstract: A phase control device includes: at least one switching element connected to an AC power source, the switching element being capable of: turning on and off at specified timings; delivering AC power to a load upon turn-on and cutting it off upon turn-off; and keeping an on-time from the start to the end of turn-on and an off-time from the start to the end of turn-off, the on-time and off-time being variable; a timing setting portion that sets a turn-on and turn-off timing for turning on and off the switching element; a judgment portion that judges whether or not the turn-on and turn-off timing are on at a phase within a first or second phase range; and a processor that starts turning on and off the switching element at the turn-on and turn-off timing, the processor being capable of adjusting the on-time and off-time depending on the judgment result.Type: GrantFiled: October 25, 2017Date of Patent: November 20, 2018Assignee: Konica Minolta, Inc.Inventors: Junichi Masuda, Mikiyuki Aoki, Toru Kasamatsu, Masahiro Nonoyama, Akimasa Ishikawa
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Publication number: 20180120742Abstract: A phase control device includes: at least one switching element connected to an AC power source, the switching element being capable of: turning on and off at specified timings; delivering AC power to a load upon turn-on and cutting it off upon turn-off; and keeping an on-time from the start to the end of turn-on and an off-time from the start to the end of turn-off, the on-time and off-time being variable; a timing setting portion that sets a turn-on and turn-off timing for turning on and off the switching element; a judgment portion that judges whether or not the turn-on and turn-off timing are on at a phase within a first or second phase range; and a processor that starts turning on and off the switching element at the turn-on and turn-off timing, the processor being capable of adjusting the on-time and off-time depending on the judgment result.Type: ApplicationFiled: October 25, 2017Publication date: May 3, 2018Inventors: Junichi MASUDA, Mikiyuki AOKI, Toru KASAMATSU, Masahiro NONOYAMA, Akimasa ISHIKAWA
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Patent number: 9503003Abstract: An image forming apparatus drives and rotates at least one of a photosensitive drum and a transport roller with use of a stepping motor in a multi-phase excitation mode. The image forming apparatus includes: a constant-voltage control unit controlling the stepping motor by applying a constant voltage for each phase; a constant-current control unit controlling the stepping motor by regulating an amount of current for each phase by a chopping control; a measuring unit measuring a chopping count of each phase on a per-step basis; a chopping count determination unit determining whether the chopping count of each phase is less than or equal to a predetermined count; and a control switching unit causing the constant-voltage control unit to control the stepping motor when the chopping count determination unit determines affirmatively, and causing the constant-current control unit to control the stepping motor when the chopping count determination unit determines negatively.Type: GrantFiled: July 16, 2014Date of Patent: November 22, 2016Assignee: KONICA MINOLTA, INC.Inventors: Takahiro Tsujimoto, Hideki Nakamura, Takeshi Ishida, Naoto Sugaya, Akimasa Ishikawa
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Patent number: 9268250Abstract: An image forming apparatus for performing laser exposure is provided. The image forming apparatus includes a driving circuit for supplying drive current to a laser light source in accordance with an image pulse signal; a pulse width expansion portion for expanding a pulse width of the image pulse signal supplied to the driving circuit; and an adjustment control portion for setting, based on state data indicating a state related to light emission start characteristics of the laser light source, a value of the bias current supplied as a part of the drive current to the laser light source and an amount of expansion of the pulse width in such a manner that laser light emission occurs in a period of time having a length equal to a length of a pulse width of each pulse in the image pulse signal.Type: GrantFiled: October 30, 2013Date of Patent: February 23, 2016Assignee: KONICA MINOLTA, INC.Inventors: Akimasa Ishikawa, Tatsuya Eguchi, Yohei Yamada
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Patent number: 9207561Abstract: An image forming apparatus that forms a color image by layering toner images of different colors includes: a photoreceptor on which an electrostatic latent image is formed through charging and exposure; an exposure unit performing exposure-scanning on the photoreceptor in accordance with image signal; an intensity determination unit determining exposure intensity according to image forming condition; and a timing determination unit determining a timing of inputting image signal for each scanning line, wherein the exposure unit has a delay duration differing depending on the exposure intensity and being from input of image signal of each pixel to be exposed to exposure of the pixel at the exposure intensity, and the timing determination unit obtains the delay duration corresponding to the exposure intensity, and determines the timing such that image signal of an initial pixel to be initially exposed is input the delay duration before the initial pixel is exposed.Type: GrantFiled: September 18, 2014Date of Patent: December 8, 2015Assignee: Konica Minolta, Inc.Inventors: Yohei Yamada, Tatsuya Eguchi, Akimasa Ishikawa
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Publication number: 20150077496Abstract: An image forming apparatus that forms a color image by layering toner images of different colors includes: a photoreceptor on which an electrostatic latent image is formed through charging and exposure; an exposure unit performing exposure-scanning on the photoreceptor in accordance with image signal; an intensity determination unit determining exposure intensity according to image forming condition; and a timing determination unit determining a timing of inputting image signal for each scanning line, wherein the exposure unit has a delay duration differing depending on the exposure intensity and being from input of image signal of each pixel to be exposed to exposure of the pixel at the exposure intensity, and the timing determination unit obtains the delay duration corresponding to the exposure intensity, and determines the timing such that image signal of an initial pixel to be initially exposed is input the delay duration before the initial pixel is exposed.Type: ApplicationFiled: September 18, 2014Publication date: March 19, 2015Applicant: KONICA MINOLTA, INC.Inventors: Yohei YAMADA, Tatsuya EGUCHI, Akimasa ISHIKAWA
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Publication number: 20150028791Abstract: An image forming apparatus drives and rotates at least one of a photosensitive drum and a transport roller with use of a stepping motor in a multi-phase excitation mode. The image forming apparatus includes: a constant-voltage control unit controlling the stepping motor by applying a constant voltage for each phase; a constant-current control unit controlling the stepping motor by regulating an amount of current for each phase by a chopping control; a measuring unit measuring a chopping count of each phase on a per-step basis; a chopping count determination unit determining whether the chopping count of each phase is less than or equal to a predetermined count; and a control switching unit causing the constant-voltage control unit to control the stepping motor when the chopping count determination unit determines affirmatively, and causing the constant-current control unit to control the stepping motor when the chopping count determination unit determines negatively.Type: ApplicationFiled: July 16, 2014Publication date: January 29, 2015Applicant: KONICA MINOLTA, INC.Inventors: Takahiro TSUJIMOTO, Hideki NAKAMURA, Takeshi ISHIDA, Naoto SUGAYA, Akimasa ISHIKAWA
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Publication number: 20140125751Abstract: An image forming apparatus for performing laser exposure is provided. The image forming apparatus includes a driving circuit for supplying drive current to a laser light source in accordance with an image pulse signal; a pulse width expansion portion for expanding a pulse width of the image pulse signal supplied to the driving circuit; and an adjustment control portion for setting, based on state data indicating a state related to light emission start characteristics of the laser light source, a value of the bias current supplied as a part of the drive current to the laser light source and an amount of expansion of the pulse width in such a manner that laser light emission occurs in a period of time having a length equal to a length of a pulse width of each pulse in the image pulse signal.Type: ApplicationFiled: October 30, 2013Publication date: May 8, 2014Applicant: Konica Minolta, Inc.Inventors: Akimasa Ishikawa, Tatsuya Eguchi, Yohei Yamada
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Publication number: 20130095991Abstract: A sheet folder includes a blade for bending a sheet, a pair of folding rollers for sandwiching the sheet bent by the blade, a heating unit for heating a folded part of the sheet sandwiched between the pair of folding rollers by the blade, a temperature detection unit for detecting a temperature of the folded part, and a control unit for keeping a state in which the sheet is sandwiched between the pair of folding rollers until at least one of a temperature change and a temperature of the folded part that are detected by the temperature detection unit satisfies a prescribed condition after the blade allows the sheet to be sandwiched between the pair of folding rollers.Type: ApplicationFiled: October 16, 2012Publication date: April 18, 2013Applicant: KONICA MINOLTA BUSINESS TECHNOLOGIES, INCInventors: Takeshi ISHIDA, Kiyohito TSUJIHARA, Takatoshi HAMADA, Hiroaki TAKATSU, Yohei YAMADA, Akimasa ISHIKAWA
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Patent number: 5751101Abstract: A cathode ray tube has a contact spring 30 which is fixed at one end to a shield cup 27 provided on an anode electrode 26 of an electron gun assembly and is pressed at the other end against an electrically conductive coating 3a applied to an inner wall of a funnel portion 3, so as to provide a reliable electrical connection between the anode electrode 26 and the electric conductive coating 3a and to hold the electron gun assembly coaxially in the neck portion 2. The contact spring 30 is made of an alloy material which is composed of 30-35 wt % nickel (Ni), 19-23 wt % chromium (Cr) and the balance of which is substantially iron (Fe), and which has a micro Vickers hardness of 250-400.Type: GrantFiled: January 28, 1997Date of Patent: May 12, 1998Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Hiroshi Takanobu, Akimasa Ishikawa