Patents by Inventor Akinori Maruyama
Akinori 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).
-
Patent number: 8687334Abstract: A controller 43 turns on a semiconductor switch 41 in a normal mode, and turns off the semiconductor switch 41 in a sleep mode. A bypass resistor 5 is connected in parallel to the semiconductor switch 41. A resistance value of the bypass resister 5 is so large as that in the sleep mode, a dark current is supplied to an electronic device 3 via the bypass resistor 5, and if an electric wire downstream of the bypass resistor is short-circuited, an electric current more than a permissive current is prevented from flowing to the electric wire.Type: GrantFiled: March 16, 2011Date of Patent: April 1, 2014Assignee: Yazaki CorporationInventors: Keisuke Ueta, Akinori Maruyama, Yoshihide Nakamura, Yoshinori Ikuta, Hideo Suganuma
-
Patent number: 8570700Abstract: There is provided a protection apparatus for a load circuit, capable of protecting the load circuit by simulating a fuse. A pseudo heat capacity Cth* smaller than a heat capacity of an electric wire used in the load circuit is set, and a temperature of the electric wire is calculated with reference to an arithmetic expression of heat generation amount of the electric wire, an arithmetic expression of heat radiation amount of the electric wire, a time counted by the count unit, and the pseudo heat capacity Cth*. Then, a semiconductor relay S1 is interrupted when the calculated temperature of the electric wire reaches an allowable temperature of the electric wire to protect the load circuit from heat generation.Type: GrantFiled: June 10, 2009Date of Patent: October 29, 2013Assignee: Yazaki CorporationInventors: Akinori Maruyama, Yoshihide Nakamura, Keisuke Ueta
-
Publication number: 20130249696Abstract: A load circuit disconnection detector includes: a current sensor (16) for detecting current flowing through a wire (W1) of a load circuit; and a protective device (100) for estimating temperature of the wire (W1) based on the detected current and forcibly turning off a semiconductor switch (Q1) if the estimated temperature of the wire reaches threshold temperature. The load circuit disconnection detector determines that there is a connection failure in the load circuit if a temperature increase calculated by a temperature calculation unit (24) is zero even a predetermined time (P1) after the semiconductor switch (Q1) is turned on.Type: ApplicationFiled: November 29, 2011Publication date: September 26, 2013Applicant: Yazaki CorporationInventors: Yoshinori Ikuta, Akinori Maruyama, Yoshihide Nakamura, Keisuke Ueta
-
Publication number: 20130253722Abstract: An electric power distribution device sets a first threshold and a second threshold for a threshold temperature of main wires, and sets a third threshold and a fourth threshold for a threshold temperature of branch wires. In the case where a temperature of each of the main wires reaches the first threshold, all of branch wire switches provided in a branch wire distributor are shut off. Thereafter, in the case where the temperature of the main wire reaches the second threshold, each of the main wire switches, which is provided a main wire distributor, is shut off. In the case where a temperature of a certain branch wire reaches the third threshold, the corresponding branch wire switch is subjected to PWM control. Thereafter, in the case where the temperature of the branch wire reaches the fourth threshold, the corresponding branch wire switch is shut off.Type: ApplicationFiled: November 30, 2011Publication date: September 26, 2013Applicant: YAZAKI CORPORATIONInventors: Yoshihide Nakamura, Akinori Maruyama, Yoshinori Ikuta, Keisuke Ueta
-
Publication number: 20130250463Abstract: A load circuit protective device calculates increasing temperature of wire of a load circuit with a first predetermined sampling period (dt1) determined by a clock signal for normal operation when a semiconductor relay (Q1) is on to estimate the temperature of the wire. The temperature of the wire is therefore estimated with high accuracy. Moreover, when the semiconductor relay (Q1) is off, the load circuit protective device calculates decreasing temperature of the wire of the load circuit with a second predetermined sampling period (dt2) to estimate the temperature of the wire. The second predetermined sampling period (dt2) is determined by a clock signal for power-saving operation and is longer than the first predetermined sampling period (dt1). Accordingly, the calculation times of the temperature can be reduced, and the power consumption is therefore reduced.Type: ApplicationFiled: November 18, 2011Publication date: September 26, 2013Inventors: Keisuke Ueta, Akinori Maruyama, Yoshihide Nakamura, Yoshinori Ikuta
-
Patent number: 8437110Abstract: A protection apparatus of a load circuit, comprises: a temperature estimation unit configured to estimate a temperature of an electric wire based on a pseudo-temperature arithmetic expression; and a breaking control unit configured to break a switch portion when the temperature estimated by the temperature estimation unit has reached an allowed temperature of the electric wire. The pseudo-temperature arithmetic expression is set in such a manner that, in a temperature arithmetic expression of the electric wire, the temperature arithmetic expression using the elapsed time counted by the timer, the current detected by the current detection unit, and a heat capacity and conductor resistance of the electric wire, a pseudo-heat capacity smaller than the heat capacity of the electric wire is assigned to the heat capacity, and a pseudo-conductor resistance larger than the conductor resistance of the electric wire is assigned to the conductor resistance.Type: GrantFiled: April 15, 2009Date of Patent: May 7, 2013Assignee: Yazaki CorporationInventors: Yoshihide Nakamura, Akinori Maruyama, Keisuke Ueta
-
Publication number: 20120081825Abstract: A protection apparatus for a load circuit is provided which can miniaturize electric wires and semiconductor switches by using a switch circuit simulating the current interruption time characteristics of fuses. A conductor resistance r and a heat resistance R used in each of a heat generation temperature calculation expression and a heat dissipation temperature calculation expression are respectively changed into a pseudo conductor resistance r* and a pseudo heat resistance R*, then the heat generation amount and the heat dissipation amount of the electric wire are calculated, and current temperature of the electric wire is estimated. When the estimation temperature reaches allowable temperature, an electronic switch S1 is turned off to thereby protect the load circuit. As a result, each of the electric wires and the semiconductor switches used in the load circuit can be protected from over heat.Type: ApplicationFiled: May 19, 2010Publication date: April 5, 2012Applicant: YAZAKI CORPORATIONInventors: Yoshihide Nakamura, Akinori Maruyama, Keisuke Ueta
-
Publication number: 20110242716Abstract: To provide a protection circuit for a load circuit which can distinguish between an overcurrent generated at a load and a rush current generated at the time of turning on a semiconductor switch or switches provided on the downstream side of the semiconductor switch and can turn the semiconductor switch off only when the overcurrent is generated to thereby protect the load circuit. A comparator CMP1 compares a detection current I1 detected by an ampere meter 15 with a threshold current Iref set in advance. When the detection current I1 reaches the threshold current Iref, the semiconductor switch 11 is turned off to thereby protect the load circuit. Further, a voltage Vd on an electric wire coupling between a battery VB and the semiconductor switch 11 is measured. When a counter electromotive force is generated and the voltage Vd reduces, the threshold current Iref is reduced according to the voltage reduction.Type: ApplicationFiled: December 24, 2009Publication date: October 6, 2011Applicant: YAZAKI CORPORATIONInventors: Keisuke Ueta, Akinori Maruyama, Yoshihide Nakamura
-
Publication number: 20110228429Abstract: A controller 43 turns on a semiconductor switch 41 in a normal mode, and turns off the semiconductor switch 41 in a sleep mode. A bypass resistor 5 is connected in parallel to the semiconductor switch 41. A resistance value of the bypass resister 5 is so large as that in the sleep mode, a dark current is supplied to an electronic device 3 via the bypass resistor 5, and if an electric wire downstream of the bypass resistor is short-circuited, an electric current more than a permissive current is prevented from flowing to the electric wire.Type: ApplicationFiled: March 16, 2011Publication date: September 22, 2011Inventors: Keisuke UETA, Akinori Maruyama, Yoshihide Nakamura, Yoshinori Ikuta, Hideo Suganuma
-
Publication number: 20110080681Abstract: There is provided a protection apparatus for a load circuit, capable of protecting the load circuit by simulating a fuse. A pseudo heat capacity Cth* smaller than a heat capacity of an electric wire used in the load circuit is set, and a temperature of the electric wire is calculated with reference to an arithmetic expression of heat generation amount of the electric wire, an arithmetic expression of heat radiation amount of the electric wire, a time counted by the count unit, and the pseudo heat capacity Cth*. Then, a semiconductor relay S1 is interrupted when the calculated temperature of the electric wire reaches an allowable temperature of the electric wire to protect the load circuit from heat generation.Type: ApplicationFiled: June 10, 2009Publication date: April 7, 2011Applicant: YAZAKI CORPORATIONInventors: Akinori Maruyama, Yoshihide Nakamura, Keisuke Ueta
-
Publication number: 20110043958Abstract: A protection apparatus of a load circuit, comprises: a temperature estimation unit configured to estimate a temperature of an electric wire based on a pseudo-temperature arithmetic expression; and a breaking control unit configured to break a switch portion when the temperature estimated by the temperature estimation unit has reached an allowed temperature of the electric wire. The pseudo-temperature arithmetic expression is set in such a manner that, in a temperature arithmetic expression of the electric wire, the temperature arithmetic expression using the elapsed time counted by the timer, the current detected by the current detection unit, and a heat capacity and conductor resistance of the electric wire, a pseudo-heat capacity smaller than the heat capacity of the electric wire is assigned to the heat capacity, and a pseudo-conductor resistance larger than the conductor resistance of the electric wire is assigned to the conductor resistance.Type: ApplicationFiled: April 15, 2009Publication date: February 24, 2011Inventors: Yoshihide Nakamura, Akinori Maruyama, Keisuke Ueta
-
Publication number: 20080186645Abstract: A relay control apparatus includes a relay contact, a relay coil which turns on the relay contact when the relay coil is electrically conducted, and a current control unit which controls a first current and a second current. The first current is larger in a current amount per unit time than the second current. The current control unit controls to flow the first current through the relay coil until a predetermined time has elapsed from a beginning of an electrical conduction of the relay coil. The current control unit controls to start to flow the second current through the relay coil on or before the predetermined time has elapsed to maintain a turn-on state of the relay contact. The predetermined time is longer than a chattering time in which a chattering in the relay contact occurs at the beginning of the electrical conduction.Type: ApplicationFiled: November 30, 2007Publication date: August 7, 2008Applicant: YAZAKI CORPORATIONInventors: Mitsuaki MORIMOTO, Akinori MARUYAMA, Akiyoshi KANAZAWA, Takashi GO HARA
-
Patent number: 6717366Abstract: An apparatus for controlling power supply for use in a vehicle causes a lamp load to blink by power supply from an in-vehicle battery or generator. The power to be supplied to the lamp load is stepwise decrease whenever a blinking time of the lamp load passes prescribed times. In this configuration a lamp load can blink for a longer time without saving power excessively.Type: GrantFiled: September 28, 2000Date of Patent: April 6, 2004Assignee: Yazaki CorporationInventor: Akinori Maruyama