Patents Assigned to TDK-Lambda Corporation
  • Publication number: 20120306386
    Abstract: An LED drive device whose power dissipation can be effectively reduced without halting current supply to an LED row as well as an LED illuminating device with the LED drive device incorporated therein. When an LED 21A making up an LED row 3A has developed a short-circuit fault, a voltage corresponding to a forward voltage which has been applied to the faulty LED 21A is impressed additionally to an FET 31A for electric power consumption thereof to increase to not less than a certain value. At this time, a power limiting circuit 6A varies a potential, being a reference value of a constant current circuit 7A, at a connecting point between voltage dividing resistors 46A, 47A and then continues to supply a certain level of a current IF1 to the LED row 3A so as to keep the remaining fault-free LEDs 22A to 26A lighting. Consequently, in the event of a short-circuit fault of the LED 21A, the adverse effect caused by discontinuing the current supply to the LED row 3A can be swept away.
    Type: Application
    Filed: June 6, 2011
    Publication date: December 6, 2012
    Applicant: TDK-LAMBDA CORPORATION
    Inventor: Kazunori Oshima
  • Patent number: 8327162
    Abstract: Even if a network setting changes due to power interruption or the like, communication for controlling the operating status of load devices of an uninterruptible power supply is enabled to continue. A network communication system (1) for the uninterruptible power supply comprises UPS member controllers (12 and 13) and a UPS group controller (11) which are connected in a network (2) to control the operating status of the load devices (3) of the uninterruptible power supply (1). The UPS group controller (11) and the UPS member controllers (12 and 13) execute data communication according to a predetermined communication protocol (Internet Protocol or the like) through the network (2), and these controllers transmit/receive data in which specific identification information issued for each of the UPS member controllers (12 and 13) is added to control data as communication data in the data communication according to the predetermined communication protocol.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: December 4, 2012
    Assignee: TDK-Lambda Corporation
    Inventors: Fujitaka Togashi, Masato Suzuki, Masataka Ookawa
  • Patent number: 8285400
    Abstract: There is provided a digital controller which can reduce a variation in output voltage as compared to the conventional digital controller at the time of abrupt changes in load and in input of a power amplifier. The digital controller is built in the power amplifier for supplying an output voltage vo to a load and is equipped with a manipulated variable calculating unit which detects the output voltage vo to calculate a manipulated variable ?1 and a signal generating unit which converts the manipulated variable ?1 into a signal for making the power amplifier operate. A feedforward function from an equivalent disturbance qy caused by the variation in the load is replaced by a feedback function from the output voltage vo and the manipulated variable ?1, thereby allowing a transfer characteristic from the disturbance qy to the output voltage vo to result in a quadratic differential characteristic.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: October 9, 2012
    Assignee: TDK-Lambda Corporation
    Inventors: Kouji Higuchi, Kazushi Nakano, Tatsuyoshi Kajikawa, Eiji Takegami, Kazushi Watanabe, Satoshi Tomioka
  • Publication number: 20110310637
    Abstract: A controller controls a voltage-source power converter and a current-source power converter based on a detection value of a rail voltage input to the voltage-source power converter and a detection value of a charging voltage output from the current-source power converter, at the time of charging operation.
    Type: Application
    Filed: June 13, 2011
    Publication date: December 22, 2011
    Applicant: TDK-LAMBDA CORPORATION
    Inventor: Eiji TAKEGAMI
  • Publication number: 20110310636
    Abstract: A DC-DC converter includes a current-source power converter that converts direct current into alternating current; a transformer that transforms the voltage of the alternating current output from the current-source power converter; a rectifier that converts the alternating current the voltage of which has been transformed by the transformer, into direct current; and a capacitor that is connected in series with winding of the transformer on the rectifier side, and blocks a direct-current component from being applied to the transformer.
    Type: Application
    Filed: June 13, 2011
    Publication date: December 22, 2011
    Applicant: TDK-LAMBDA CORPORATION
    Inventor: Kazuki IWAYA
  • Publication number: 20110305852
    Abstract: In a method of machining an electronic circuit substrate in which a sub-substrate is attached to a main substrate, an electronic circuit substrate and a method of machining the same in which the sub-substrate can be attached to the main substrate with high degree of accuracy are provided without forming the arcuate portions at corners of the outline of the substrate and corners of an insertion hole even when a router is used for machining substrates.
    Type: Application
    Filed: May 18, 2011
    Publication date: December 15, 2011
    Applicant: TDK-LAMBDA CORPORATION
    Inventor: Hiroshi SUGAYA
  • Publication number: 20110291579
    Abstract: The present invention is capable of continuously applying an optimum starting waveform to a discharge lamp using a simple-enough circuit configuration. A starting circuit is connected to output terminals of an inverter, and the starting circuit outputs to a discharge lamp an output voltage Vout capable of starting the discharge lamp that is a load, upon receiving an AC power with a high frequency from the inverter at the start of the discharge lamp. Further, the starting circuit is connected to output terminals of the inverter, and comprises two windings connected to the output terminals of the inverter and serially connected to the discharge lamp; a first capacitor connected between an output terminal of the first winding and an input terminal of the second winding; and a second capacitor connected between an input terminal of the first winding and an output terminal of the second winding.
    Type: Application
    Filed: June 1, 2011
    Publication date: December 1, 2011
    Applicant: TDK-LAMBDA CORPORATION
    Inventors: Takumi Horikawa, Akihiko Oohira, Kikuro Sasayama
  • Publication number: 20110273257
    Abstract: An edgewise coil achieves positioning of both end portions and accurate and reliable conduction with respect to a circuit board in a simple configuration, and can be downsized. The edgewise coil is usable in a conductor. The edgewise coil includes a base material and a coil member fixed at both end portions to the base material and including an external wound-wire portion placed on the base material and an internal wound-wire portion extending in the base material.
    Type: Application
    Filed: January 12, 2011
    Publication date: November 10, 2011
    Applicant: TDK-Lambda Corporation
    Inventor: Kazuki ISHIZAWA
  • Publication number: 20110266043
    Abstract: It is an object of the invention to provide a substrate which allows visual confirmation of the joint state and improvement of reliability of the joint between the components and the substrate to be mounted. The substrate is configured to mount a component having a planer terminal and include a land subjected to solder joint with respect to the terminal of the component. A substrate includes notched portions formed by notching parts of the lands in the direction away from an end surface forming the space. The each land on the substrate includes a first land formed on the substrate and a second land formed of an end surface of the notched portion in the direction of thickness of the substrate. Therefore, visibility of parts of terminals of components is secured utilizing penetration of the notched portions at the time of soldering, so that the joint state of soldering can be visually confirmed.
    Type: Application
    Filed: January 7, 2011
    Publication date: November 3, 2011
    Applicant: TDK-Lambda Corporation
    Inventors: Takeshi UESUGI, Daisuke Fujisaki
  • Publication number: 20110255315
    Abstract: A switching power supply device ensuring no voltage dip is caused by a sink current even if started with output voltage accumulated. When input voltage Vi is reapplied with output voltage Vo accumulated, supplying PWM signals to main switching element 9 and rectifying switching elements is stopped by output detection circuit 21 until a voltage produced by dividing output voltage Vo decreases to a first threshold allowable for energy caused by a sink current. Accordingly, inflow of the sink current immediately after reapplication of input voltage and the subsequent voltage dip are inhibited. Afterward, when the voltage produced by dividing the output voltage Vo decreases to the first threshold and then main switching element starts operating by PWM signal from control circuit 22, drive detection circuit 31 detects this condition to permit supplying PWM signal to rectifying switching elements 10, enabling inhibition of the subsequent inflow of the sink current.
    Type: Application
    Filed: April 15, 2011
    Publication date: October 20, 2011
    Applicant: TDK-Lambda Corporation
    Inventor: Masayoshi Ono
  • Publication number: 20110187288
    Abstract: A discharge lamp lighting device capable of preventing magnetic saturation of an inductor connected with an output of an inverter. An inverter 12 comprises a first set of switching elements 32, 33 for switching an output voltage of the inverter 12 to a positive polarity and a second set of switching elements 31, 34 for switching the output voltage thereof to a negative polarity. At the start-up of a lamp 20, each of the switching elements 31 to 34 is allowed to perform switching operations in such a pattern that after turning on and off the first set of the switching elements 32, 33 more than once, the second set of switching elements 31, 34 are allowed to turn or and off more than once. Accordingly, energy stored in the inductor 37 is discharged during a temporary off-period, thus permitting the inductor 37 to be prevented from being magnetically saturated.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 4, 2011
    Applicants: TDK-Lambda Corporation, Seiko Epson Corporation
    Inventors: Takumi Horikawa, Kikuro Sasayama, Kenichi Kitagawa
  • Patent number: 7964300
    Abstract: There is provided a risk-free and easy-to-use battery pack using battery cells 1 as a secondary battery, in which internal gases evaporated by applying overvoltage or the like thereto are processed inside a case to be prevented from leaking to the outside of the case and thereby even if the case has been led to rise in pressure due to a thermorunaway of the battery, the case is free from breaking. To realize this performance, the battery pack 10 is provided with a battery cell housing 17 for housing lithium cells 1 and a gas processor 15 for liquefying the internal gases g generated from the lithium cells 1.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: June 21, 2011
    Assignee: TDK-Lambda Corporation
    Inventors: Hiroshi Nakazawa, Katsuhiko Nakane
  • Patent number: 7859226
    Abstract: A method and device for safety protection of a secondary battery capable of preventing smoking and ignition thereof. A lithium cell 1 as a chargeable and dischargeable secondary battery, a protection circuit 11 for shutting down charging power Pc at the time of overcurrent, overvoltage, etc., and an electric power restriction circuit 20 for limiting the charging power Pc input to the lithium cell 1 are incorporated into a battery pack 10. A battery charger 12, equipped with a stabilized electric source 13 and a charging circuit 14, inputting the charging power Pc to the lithium cell 1, is connected to a previous stage of the battery pack 10. The electric power restriction circuit 20 limits the charging power Pc within a boundary value Pmax of a safety operation region for safely using the lithium cell 1, thereby permitting the lithium cell 1 to operate safely under any conditions.
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: December 28, 2010
    Assignee: TDK-Lambda Corporation
    Inventors: Hiroshi Nakazawa, Masayuki Kato, Yasuo Nagasawa
  • Publication number: 20100259856
    Abstract: A power supply control device for controlling power supply to a pair of terminals to which a load is connected, comprising a voltage measuring part for measuring a voltage which has a predetermined relationship with the voltage of the pair of terminals, a short circuit detecting part for detecting whether a short circuit exists between the pair of terminals based on the measured voltage and for making power supply to the pair of terminals stop when existence of a short circuit is detected, and a constant current supplying part for supplying a constant current though the pair of terminals; wherein the short circuit detecting part is configured to detect that the previously detected short circuit is eliminated when the voltage measured by the voltage measuring part is equal to or greater than a predetermined threshold value upon supplying the constant current through the pair of terminals.
    Type: Application
    Filed: March 25, 2010
    Publication date: October 14, 2010
    Applicants: TDK-Lambda Corporation, TDK Corporation
    Inventors: Tadao Senriuchi, Masahiko Hirokawa, Takumi Sakamoto, Hiroshi Nakazawa, Noriyuki Hirao
  • Publication number: 20100259270
    Abstract: A number of cells can be determined before control for a battery without providing cell number setting and input means. The cell number determination device comprises voltage measuring units that select an “i”th cell among cells that are connected in series and that configure a battery, and that measure a voltage value between a terminal in which the “i”th cell and an (i?1)th cell, which is in one location higher than the “i”th cell, are connected and a ground potential line, voltage comparators that determine an existence, nonexistence or normality of the cells by comparing a voltage value of an (i+1)th cell that is in one location lower than the “i”th cell with the voltage value of the “i”th cell measured by the voltage measuring units and a cell number determination unit that determines a number of assembled cells and normal cells and cell assembled locations in the battery.
    Type: Application
    Filed: March 25, 2010
    Publication date: October 14, 2010
    Applicants: TDK-Lambda Corporation, TDK Corporation
    Inventors: Tadao Senriuchi, Masahiko Hirokawa, Takumi Sakamoto, Hiroshi Nakazawa, Noriyuki Hirao
  • Publication number: 20100259222
    Abstract: A reusable period of a battery can be maintained for a long time by recharging while avoiding abnormal heating of the battery due to over discharge. A battery protection circuit comprises a control part that cuts off a discharge switch which is a discharge path to a load for a battery when a voltage value of the battery is equal to or less than a first threshold value, or when the voltage value of the battery is less than the first threshold value, wherein the control part cuts off a power switch as a power supply path to the control part itself when the voltage value of the battery is equal to or less than a second threshold value, or when the voltage value of the battery is less than the second threshold value which is lower than the first threshold value.
    Type: Application
    Filed: March 25, 2010
    Publication date: October 14, 2010
    Applicants: TDK-Lambda Corporation, TDK Corporation
    Inventors: Tadao Senriuchi, Masahiko Hirokawa, Takumi Sakamoto, Hiroshi Nakazawa, Noriyuki Hirao
  • Publication number: 20100165664
    Abstract: A primary circuit turns on switching elements and generates energy from a direct-current power supply to a secondary circuit through a transformer. The secondary circuit charges a driven element using the energy obtained from the primary circuit through the transformer, turns on a switching element, discharges the energy accumulated in the driven element, and generates the energy in the primary circuit through the transformer. The primary circuit returns the energy obtained from the secondary circuit to the direct-current power supply.
    Type: Application
    Filed: December 22, 2009
    Publication date: July 1, 2010
    Applicant: TDK-LAMBDA CORPORATION
    Inventor: Hiroto Terashi
  • Publication number: 20100114399
    Abstract: There is provided a digital controller which can reduce a variation in output voltage as compared to the conventional digital controller at the time of abrupt changes in load and in input of a power amplifier. The digital controller is built in the power amplifier for supplying an output voltage vo to a load and is equipped with a manipulated variable calculating unit which detects the output voltage vo to calculate a manipulated variable ?1 and a signal generating unit which converts the manipulated variable ?1 into a signal for making the power amplifier operate. A feedforward function from an equivalent disturbance qy caused by the variation in the load is replaced by a feedback function from the output voltage vo and the manipulated variable ?1, thereby allowing a transfer characteristic from the disturbance qy to the output voltage vo to result in a quadratic differential characteristic.
    Type: Application
    Filed: December 11, 2007
    Publication date: May 6, 2010
    Applicants: UNIVERSITY OF ELECTRO-COMMUNICATIONS, TDK-LAMBDA CORPORATION, KABUSHIKI KAISHA CAMPUSCREATE
    Inventors: Kouji Higuchi, Kazushi Nakano, Tatsuyoshi Kajikawa, Eiji Takegami, Kazushi Watanabe, Satoshi Tomioka
  • Publication number: 20100103711
    Abstract: Performance failure in an uninterruptible power supply (UPS) is determined independently by itself. A selective tripping can be done within a shorter time than one cycle of an AC output. A UPS converts a DC voltage to an AC voltage and supplies the AC voltage to a load device. A UPS has a control unit conducting a failure determination by using an instantaneous value of an internal voltage and current. It is preferred that a UPS includes an inverter unit and a trip switch. The inverter unit includes a semiconductor bridge circuit generating a sinusoidal AC voltage by modulating a DC voltage with voltage instruction values, and a filter circuit inserted between the semiconductor bridge circuit and the load device. The trip switch connects and trips a connection between the inverter unit and the load device according to the failure determination of the control unit.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 29, 2010
    Applicant: TDK-Lambda Corporation
    Inventor: Yoshihiro Komatsuzaki
  • Publication number: 20100102634
    Abstract: UPS performance failure is determined independently by itself. Selective tripping can be done within a shorter time than one cycle of an AC output. A UPS converts a DC voltage to an AC voltage and supplies the AC voltage to a load device. A UPS has a control unit identifying a resistance value of an internal resistance as an internal impedance of the UPS by using an instantaneous value of an internal voltage and current and conducting a failure determination by detecting abnormal fluctuation of the value. It is preferred that an identification of the internal impedance is done through a system identification unit.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 29, 2010
    Applicant: TDK-Lambda Corporation
    Inventor: Yoshihiro Komatsuzaki