Patents by Inventor Yoshiki Takagi
Yoshiki Takagi 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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Publication number: 20180064885Abstract: A medical needle is provided with a needle body and a protector including a housing space which houses the needle body after venipuncture by the needle body by relative movement of the needle body in an axial direction. The protector has an annular recess in the entire circumference in the circumferential direction of an inner face in the housing space so as to accumulate blood that spatters from the needle body.Type: ApplicationFiled: March 24, 2016Publication date: March 8, 2018Applicant: TERUMO KABUSHIKI KAISHAInventors: Yuusuke Yamazaki, Noriko Naka, Yasushi Tabata, Nobukazu Akaike, Yoshiki Takagi
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Publication number: 20140070779Abstract: A switching regulator includes a coil, switching transistor, a synchronous rectifying transistor, a switching control circuit, a comparator, a first buffer circuit operated by an input voltage, and a second buffer circuit operated by an output voltage. The switching control circuit assumes control such that control signals are outputted from the first buffer circuit to a switching transistor and a synchronous rectifying transistor, respectively, in response to a power supply switching signal indicating that the output voltage is lower than the input voltage, while the switching control circuit assumes control such that the control signals are outputted from the second buffer circuit to the switching transistor and the synchronous rectifying transistor, respectively, in response to the power supply switching signal indicating that the output voltage is equal to or higher than the input voltage.Type: ApplicationFiled: September 11, 2013Publication date: March 13, 2014Applicant: RICOH COMPANY, LTD.Inventors: Yoshiki Takagi, Yuki Kashima
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Patent number: 8242760Abstract: A constant-voltage circuit converts a voltage input to an input terminal and outputs a predetermined constant voltage from an output terminal. The constant-voltage circuit includes an output transistor to output an electrical current to the output terminal in response to a control signal, a reference voltage circuit to generate a predetermined reference voltage, a control circuit to adjust a voltage proportional to the output voltage output from the output terminal to the reference voltage output from the reference voltage circuit by controlling the output transistor and a soft start circuit including a capacitor for soft start that is charged at start-up and a current control unit to control an electrical current supplied to the reference voltage circuit. The current control unit adjusts the reference voltage to a voltage determined by the capacitor for soft start at the start-up until the reference voltage reaches a desired voltage.Type: GrantFiled: August 25, 2009Date of Patent: August 14, 2012Assignee: Ricoh Company, Ltd.Inventors: Yoshiki Takagi, Kenichi Watanabe
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Patent number: 8129966Abstract: A voltage regulator circuit and control method therefor. The circuit includes input and output terminals, an output transistor to pass a current from the input terminal to the output terminal according to a control signal, a reference voltage generator unit to generate and output a reference voltage, an output voltage detector unit to detect an output voltage output from the output terminal and generate and output a proportional voltage proportional to a detected voltage, a first error amplifier unit to control the output transistor to make the proportional voltage equal to the reference voltage, and a second error amplifier unit to respond to fluctuation in the output voltage faster than the first error amplifier unit and increase the output current from the output transistor for a period of time when the output voltage rapidly drops. Current consumption of the second error amplifier unit is changed according to the output current.Type: GrantFiled: March 4, 2008Date of Patent: March 6, 2012Assignee: Ricoh Company, Ltd.Inventor: Yoshiki Takagi
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Patent number: 7847530Abstract: A voltage regulator is disclosed that includes first and second output transistors each outputting a current from the input terminal to the output terminal of the voltage regulator; and a control circuit part controlling the operations of the first and second output transistors to equalize a voltage proportional to an output voltage with a reference voltage. The control circuit part includes first and second error amplifier circuits each amplifying and outputting the difference between the proportional and reference voltages. The second error amplifier circuit consumes a smaller amount of current than the first error amplifier circuit. The control circuit part controls the output voltage by controlling the operations of the first and second output transistors using the first error amplifier circuit or controlling the operation of the second output transistor using the second error amplifier circuit in accordance with a control signal externally input to the control circuit part.Type: GrantFiled: July 27, 2007Date of Patent: December 7, 2010Assignee: Ricoh Company, Ltd.Inventor: Yoshiki Takagi
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Patent number: 7821242Abstract: A constant voltage circuit for converting an input voltage input from an input terminal, converting the input voltage to a predetermined constant voltage, and outputting the converted voltage from an output terminal is disclosed that includes an output transistor for outputting a current corresponding to a control signal from the input terminal to the output terminal, a control circuit part for controlling operation of the output transistor so that a proportional voltage proportional to the voltage output from the output terminal is equal to a reference voltage, and a pseudo-load current control circuit part for supplying a pseudo-load current from the output terminal when detecting that the output transistor is switched off according to a voltage difference between the input voltage and a voltage of a gate of the output transistor.Type: GrantFiled: May 22, 2007Date of Patent: October 26, 2010Assignee: Ricoh Company, Ltd.Inventor: Yoshiki Takagi
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Patent number: 7772817Abstract: A constant voltage circuit which is capable of quickly responding to a sudden change of an output voltage includes an output transistor, and first and second error amplifiers. The output transistor outputs a power with an output voltage and an output current to a load. The first error amplifier is configured to increase a response speed with respect to changes of the output voltage in accordance with an increase of the output current so as to control operations of the output transistor. The second error amplifier has a response speed faster than the first error amplifier with respect to changes of the output voltage, and is configured to decrease a gain thereof in response to a drain current of the output transistor.Type: GrantFiled: August 11, 2008Date of Patent: August 10, 2010Assignee: Ricoh Company, Ltd.Inventors: Yoshiki Takagi, Yusuke Minakuchi
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Publication number: 20100156367Abstract: A constant voltage circuit for converting an input voltage input from an input terminal, converting the input voltage to a predetermined constant voltage, and outputting the converted voltage from an output terminal is disclosed that includes an output transistor for outputting a current corresponding to a control signal from the input terminal to the output terminal, a control circuit part for controlling operation of the output transistor so that a proportional voltage proportional to the voltage output from the output terminal is equal to a reference voltage, and a pseudo-load current control circuit part for supplying a pseudo-load current from the output terminal when detecting that the output transistor is switched off according to a voltage difference between the input voltage and a voltage of a gate of the output transistor.Type: ApplicationFiled: May 22, 2007Publication date: June 24, 2010Inventor: Yoshiki Takagi
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Publication number: 20100052636Abstract: A constant-voltage circuit converts a voltage input to an input terminal and outputs a predetermined constant voltage from an output terminal. The constant-voltage circuit includes an output transistor to output an electrical current to the output terminal in response to a control signal, a reference voltage circuit to generate a predetermined reference voltage, a control circuit to adjust a voltage proportional to the output voltage output from the output terminal to the reference voltage output from the reference voltage circuit by controlling the output transistor and a soft start circuit including a capacitor for soft start that is charged at start-up and a current control unit to control an electrical current supplied to the reference voltage circuit. The current control unit adjusts the reference voltage to a voltage determined by the capacitor for soft start at the start-up until the reference voltage reaches a desired voltage.Type: ApplicationFiled: August 25, 2009Publication date: March 4, 2010Applicant: RICOH COMPANY, LTD.Inventors: Yoshiki TAKAGI, Kenichi Watanabe
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Publication number: 20090278518Abstract: A voltage regulator is disclosed that includes first and second output transistors each outputting a current from the input terminal to the output terminal of the voltage regulator; and a control circuit part controlling the operations of the first and second output transistors to equalize a voltage proportional to an output voltage with a reference voltage. The control circuit part includes first and second error amplifier circuits each amplifying and outputting the difference between the proportional and reference voltages. The second error amplifier circuit consumes a smaller amount of current than the first error amplifier circuit. The control circuit part controls the output voltage by controlling the operations of the first and second output transistors using the first error amplifier circuit or controlling the operation of the second output transistor using the second error amplifier circuit in accordance with a control signal externally input to the control circuit part.Type: ApplicationFiled: July 27, 2007Publication date: November 12, 2009Applicant: RICOH COMPANY, LTD.Inventor: Yoshiki Takagi
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Patent number: 7598807Abstract: A differential amplifier circuit, a voltage regulator using the differential amplifier circuit, and a method for controlling the differential amplifier circuit. The circuit includes a differential pair having a plurality of transistors, a first bias current generator circuit part to generate a first bias current to the differential pair, and a first bias current control circuit part to control a supply of the first bias current to the differential pair in response to a switching signal from outside, wherein the first bias current generator circuit part changes a current value of the first bias current in response to the switching signal.Type: GrantFiled: September 4, 2007Date of Patent: October 6, 2009Assignee: Ricoh Company, Ltd.Inventor: Yoshiki Takagi
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Patent number: 7538537Abstract: A constant-voltage circuit in which a response speed for a sudden change of an input voltage or a sudden change of a load current can be fast are disclosed. In normal operating conditions, a first control circuit (error amplifier circuit) having an excellent direct-current characteristic controls operations of an output voltage control transistor and an output voltage is made a constant voltage. When the output voltage is suddenly decreased, before the first control circuit controls the operations of the output voltage control transistor by responding to the sudden decrease of the output voltage, an amplifier circuit having a high-speed response characteristic amplifies the change of the output voltage, and when the amplified voltage obtained by the amplification is suddenly decreased, a second control circuit controls the operations of the output voltage control transistor for a predetermined period. With this, the output voltage can be a constant voltage.Type: GrantFiled: October 23, 2006Date of Patent: May 26, 2009Assignees: Ricoh Company, Ltd., Analog Research LimitedInventors: Yusuke Minakuchi, Yoshiki Takagi
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Publication number: 20090015222Abstract: A constant voltage circuit which is capable of quickly responding to a sudden change of an output voltage includes an output transistor, and first and second error amplifiers. The output transistor outputs a power with an output voltage and an output current to a load. The first error amplifier is configured to increase a response speed with respect to changes of the output voltage in accordance with an increase of the output current so as to control operations of the output transistor. The second error amplifier has a response speed faster than the first error amplifier with respect to changes of the output voltage, and is configured to decrease a gain thereof in response to a drain current of the output transistor.Type: ApplicationFiled: August 11, 2008Publication date: January 15, 2009Inventors: Yoshiki Takagi, Yusuke Minakuchi
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Publication number: 20080281247Abstract: An autonomic nervous activity monitor capable of predicting occurrence of abnormal reaction depending on autonomic nervous activity and used for medical practice and the like is provided. A blood component collecting apparatus 100 carries out frequency analysis to a pattern of heartbeat which is acquired by an ECG 300 from a donor, and calculates a high frequency component value [msec2] defined as an indicator for parasympathetic activity and a ratio value of a low frequency component to the high frequency component defined as an indicator for sympathetic activity to detect a change in these values on a time-series base. When a judgment circuit 204 predicts that abnormal reaction may occur to a donor after blood collection operation is started, a controller 200 controls a pump 9 to decrease a blood drawing or blood returning speed, or, to stop blood drawing or blood returning operation.Type: ApplicationFiled: July 11, 2008Publication date: November 13, 2008Applicants: Japanese Red Cross Society, TERUMO KABUSHIKI KAISHAInventors: Kenji Tadokoro, Fumiko Saitou, Yoshiki Takagi
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Patent number: 7429852Abstract: A constant voltage circuit which is capable of quickly responding to a sudden change of an output voltage includes an output transistor, and first and second error amplifiers. The output transistor outputs a power with an output voltage and an output current to a load. The first error amplifier is configured to increase a response speed with respect to changes of the output voltage in accordance with an increase of the output current so as to control operations of the output transistor. The second error amplifier has a response speed faster than the first error amplifier with respect to changes of the output voltage, and is configured to decrease a gain thereof in response to a drain current of the output transistor.Type: GrantFiled: April 3, 2006Date of Patent: September 30, 2008Assignee: Ricoh Company, Ltd.Inventors: Yoshiki Takagi, Yusuke Minakuchi
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Publication number: 20080224675Abstract: A voltage regulator converts a voltage from a direct current power supply into a predetermined voltage, and outputs the predetermined voltage from an output terminal thereof to supply electric power to a load. The voltage regulator includes a first power supply circuit and a second power supply circuit. The first power supply circuit supplies the electric power to the load in accordance with a switching signal, when a load current is relatively high. The second power supply circuit supplies the electric power to the load in accordance with the switching signal, when the load current is relatively low. A bias current for operating the second power supply circuit is set to be proportional to the load current during the supply of the electric power to the load by the second power supply circuit.Type: ApplicationFiled: March 11, 2008Publication date: September 18, 2008Inventor: Yoshiki Takagi
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Publication number: 20080218139Abstract: A voltage regulator circuit and control method therefor. The circuit includes input and output terminals, an output transistor to pass a current from the input terminal to the output terminal according to a control signal, a reference voltage generator unit to generate and output a reference voltage, an output voltage detector unit to detect an output voltage output from the output terminal and generate and output a proportional voltage proportional to a detected voltage, a first error amplifier unit to control the output transistor to make the proportional voltage equal to the reference voltage, and a second error amplifier unit to respond to fluctuation in the output voltage faster than the first error amplifier unit and increase the output current from the output transistor for a period of time when the output voltage rapidly drops. Current consumption of the second error amplifier unit is changed according to the output current.Type: ApplicationFiled: March 4, 2008Publication date: September 11, 2008Inventor: Yoshiki Takagi
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Patent number: 7413548Abstract: An autonomic nervous activity monitor capable of predicting occurrence of abnormal reaction depending on autonomic nervous activity and used for medical practice and the like is provided. A blood component collecting apparatus 100 carries out frequency analysis to a pattern of heartbeat which is acquired by an ECG 300 from a donor, and calculates a high frequency component value [msec2] defined as an indicator for parasympathetic activity and a ratio value of a low frequency component to the high frequency component defined as an indicator for sympathetic activity to detect a change in these values on a time-series base. When a judgment circuit 204 predicts that abnormal reaction may occur to a donor after blood collection operation is started, a controller 200 controls a pump 9 to decrease a blood drawing or blood returning speed, or, to stop blood drawing or blood returning operation.Type: GrantFiled: March 18, 2005Date of Patent: August 19, 2008Assignees: Japanese Red Cross Society, Terumo Kabushiki KaishaInventors: Kenji Tadokoro, Fumiko Saitou, Yoshiki Takagi
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Publication number: 20080138605Abstract: There are provided a process for synthesizing a diamond thin film on a glass substrate with a high coverage even when using ordinary multi-component glass having a low glass transition point (Tg) as a material of the glass substrate, and a composite article obtained by laminating the diamond thin film on the glass substrate.Type: ApplicationFiled: November 21, 2007Publication date: June 12, 2008Inventor: Yoshiki Takagi
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Publication number: 20080061881Abstract: A differential amplifier circuit, a voltage regulator using the differential amplifier circuit, and a method for controlling the differential amplifier circuit. The circuit includes a differential pair having a plurality of transistors, a first bias current generator circuit part to generate a first bias current to the differential pair, and a first bias current control circuit part to control a supply of the first bias current to the differential pair in response to a switching signal from outside, wherein the first bias current generator circuit part changes a current value of the first bias current in response to the switching signal.Type: ApplicationFiled: September 4, 2007Publication date: March 13, 2008Inventor: Yoshiki Takagi