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81. 发明专利

JPS63276916A SWITCHING CONTROLLER 失效
公开(公告)号：JPS63276916A
公开(公告)日：1988-11-15
申请号：JP11075187
申请日：1987-05-08
申请人： HITACHI LTD
发明人： NARITA HIROSHI , KUROTAKI YOSHIMI , NAKAMURA KIYOSHI
IPC分类号： H02M1/088 , H03K17/10 , H03K17/16 , H03K17/64
摘要： PURPOSE:To simplify the circuit constitution by selecting the off-current to be a value taking the dispersion in the turn-off time of a switch main circuit into account and making the overdrive current at turn-on the same as the off- current in a signal drive circuit for switch elements connected in series. CONSTITUTION:Power transistors(TRs) 41, 42 connected in series are driven by on/off signal drive circuits 15, 17 turned on/off by a high frequency oscillator 13. Since the dispersion in the turn-off time of the TRs 41, 42 is allowed within a range, it is no required to cause an off-signal current to flow over a required value. Moreover, in selecting the overdrive current of the on-signal current the same as the off-signal current, the dispersion in the turn-on time is sufficiently decreased. Thus, since the circuits 15 and 17 comprising FETs 151, 171, transistor switches 162, 165 and 182, 185 are constituted to be the same, then the circuits are simplified.

82. 发明专利

JPS63202264A CHOPPER DEVICE 失效
公开(公告)号：JPS63202264A
公开(公告)日：1988-08-22
申请号：JP3330487
申请日：1987-02-18
申请人： HITACHI LTD
发明人： AKIYAMA HIROYUKI , TSUZUKI YOZO , NARITA HIROSHI , JINBO YOSHIJI
IPC分类号： B60L15/28 , H02M3/135
摘要： PURPOSE:To increase chopping frequency by employing the same element, by a method wherein a plurality of GTO thyristors are accommodated in one cooling vessel while the GTO thyristors are put ON alternately by a specified regulation. CONSTITUTION:Circuits, consisting of GTO thyristors, are connected in parallel and the main part of these circuits is accommodated in one set of cooling vessel (the range of the main part is shown by broken lines in a diagram). Two thyristors are operated alternately. According to this constitution, watt loss, generated in the same cooling vessel, becomes the loss corresponding to the loss of two sets of GTO thyristors, therefore, the loss, generated in one element, becomes one half of the loss generated when only one set of the thyristor is operated when the liquid temperature of refrigerant is the same as a case so far whereby as temperature rise between the liquid temperature and a junction temperature may be restrained to a reduced temperature rise.

83. 发明专利

JPS63190504A CHOPPER APPARATUS 失效
公开(公告)号：JPS63190504A
公开(公告)日：1988-08-08
申请号：JP1843287
申请日：1987-01-30
申请人： HITACHI LTD
发明人： NARITA HIROSHI
IPC分类号： B60L15/28 , H02P7/298
摘要： PURPOSE:To obtain a low-priced field switching part by making the voltage capacity of a switching element performing no chopping operation lower than that of another switching element performing chopping operation. CONSTITUTION:Electric current of a motor shunt field 10 is controlled by a field switching part where four sets of switching elements 11-14 are bridge- connected. Said switching elements 11-14 are composed of a snubber circuit consisting of GTO 111-141 and free-wheel diodes 112-142, diodes 123-143, capacitors 117-144, and resistances 118-145. In this case, free-wheel diodes 112 and 132 of switching elements 11 and 13 performing no chopping operation are provided as fast diodes with small recovery charge quantity, and said snubber circuit as a composite snubber circuit capable of making spike voltage smaller.

85. 发明专利

JPS6216002A CONTROLLER FOR INVERTER ELECTRIC ROLLING STOCK 失效
公开(公告)号：JPS6216002A
公开(公告)日：1987-01-24
申请号：JP15226385
申请日：1985-07-12
申请人： HITACHI LTD
发明人： NARITA HIROSHI
IPC分类号： B60L9/18 , B60L9/16
摘要： PURPOSE:To omit a switching means having large conduction capacitance by initially charging a filter capacitor by an auxiliary charging equipment. CONSTITUTION:When a power running command or a braking command is outputted, a chopper CH and a thyristor ThC for an auxiliary charging equipment Amux.Chg are controlled,and a capacitor CF for a filter is charged until terminal voltage VCF approximately reaches trolley voltage VS. Voltage is charged to the capacitor CF, and a switching means L1 is closed while gates for the chopper CH and the thyristor ThC are stopped. The voltage VC of the capacitor for the filter is approximately the same as trolley voltage VS at that time, thus generating vibration by a reactor Lr and the filter capacitor CF is not generated.

86. 发明专利

JPS6117203B2 JPS6117203B2 - 失效
公开(公告)号：JPS6117203B2
公开(公告)日：1986-05-06
申请号：JP3329079
申请日：1979-03-23
申请人： Hitachi Ltd
发明人： TSUBOI TAKASHI , OKAMATSU SHIGETOSHI , TAKATSU EIJI , IBAMOTO MASAHIKO , NARITA HIROSHI
IPC分类号： B60L9/12 , B60L9/16 , B60L15/20
CPC分类号： Y02T10/7258

88. 发明专利

JPS6035881B2 失效
公开(公告)号：JPS6035881B2
公开(公告)日：1985-08-17
申请号：JP2321476
申请日：1976-03-05
申请人： HITACHI LTD
发明人： NARITA HIROSHI , HORIUCHI MICHIMASA
IPC分类号： H02P3/14 , B60L7/12 , B60L15/02 , B60L15/28 , H02P7/29 , H02P7/291 , H02P7/298

89. 发明专利

JPS60102070A HEAD OUTPUT SWITCHING CIRCUIT 失效
公开(公告)号：JPS60102070A
公开(公告)日：1985-06-06
申请号：JP20908883
申请日：1983-11-09
申请人： HITACHI LTD
发明人： NARITA HIROSHI
IPC分类号： G11B5/02 , G11B15/14 , H04N5/783 , H04N5/93
摘要： PURPOSE:To attain power saving while decreasing the load of a recording amplifier and also to improve the recording and reproducing picture quality by inserting a transistor (TR) via a rotary transformer, conducting the TR at reproduction and breaking it at recording. CONSTITUTION:An HIGH voltage is fed to a base of TR32 at reproduction and TRs 30, 31, 32 are turned on. Thus, the emitter of a switching TR11 is grounded via the rotary transformer 5 in terms of AC and DC, and an output of a head 2 is fed by applying the HIGH voltage to a base (d). On the other hand, a LOW voltage is applied to a terminal (a) at recording and the TRs 30, 32 are turned off. Since the HIGH voltage is applied to terminals (b), (c), the load of the recording amplifier 25 is heads 1, 2 only, the power consumption is reduced and the frequency characteristic is also improved.

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