Circuit protection arrangements using ground fault interrupter for
overcurrent and overvoltage protection
    1.
    发明授权
    Circuit protection arrangements using ground fault interrupter for overcurrent and overvoltage protection 失效
    使用接地故障断路器进行过流保护和过电压保护的电路保护装置

    公开(公告)号:US5745322A

    公开(公告)日:1998-04-28

    申请号:US563321

    申请日:1995-11-28

    CPC分类号: H02H3/334 H02H3/105

    摘要: An electrical protection system which uses a ground fault interrupter (GFI) to protect a circuit from (A) ground faults and (B) overcurrents and/or overvoltages. For overcurrent protection, a control element may be coupled in series with the line or return input to the GFI, and a bypass element may be coupled in parallel with the control element and the GFI. In case of an overcurrent, the control element causes current to be diverted through the bypass element, thereby creating a current imbalance in the GFI circuitry causing the GFI to open the circuit. For overvoltage protection, a bypass element (e.g. a varistor) may be coupled between, e.g., the line sense input of the GFI and the return sense input of the GFI. In case of an overvoltage, the bypass element conducts current, thereby creating a current imbalance in the GFI circuitry causing the GFI to open the circuit.

    摘要翻译: 一种使用接地故障中断器(GFI)来保护电路免受(A)接地故障和(B)过电流和/或过电压的电气保护系统。 对于过电流保护,控制元件可以与GFI的线路或返回输入串联耦合,并且旁路元件可以与控制元件和GFI并联耦合。 在过电流的情况下,控制元件使电流通过旁路元件转移,从而在GFI电路中产生电流不平衡,导致GFI打开电路。 对于过电压保护,旁路元件(例如变阻器)可以耦合在例如GFI的线路感测输入和GFI的返回检测输入之间。 在过压的情况下,旁路元件导通电流,从而在GFI电路中产生电流不平衡,导致GFI打开电路。

    Overcurrent protection circuits comprising combinations of PTC devices
and switches
    2.
    发明授权
    Overcurrent protection circuits comprising combinations of PTC devices and switches 失效
    包括PTC器件和开关组合的过电流保护电路

    公开(公告)号:US5864458A

    公开(公告)日:1999-01-26

    申请号:US564465

    申请日:1995-11-29

    摘要: Electrical circuit protection arrangements with PTC devices and mechanical switches. The combinations of this invention permit the use of mechanical switches and PTC devices to switch voltages and currents in normal circuit operations, wherein the voltage and/or current ratings of the mechanical switches and PTC devices are much less than the normal operating voltages and currents of the circuits. This feature permits the use of smaller and less expensive mechanical switches and PTC device than would otherwise be required in such circuits. The arrangements of switches and PTC devices also permit the PTC devices to limit the magnitude of the fault current passed to the circuit.

    摘要翻译: 带PTC器件和机械开关的电路保护装置。 本发明的组合允许使用机械开关和PTC装置在正常电路操作中切换电压和电流,其中机械开关和PTC装置的电压和/或电流额定值远低于正常工作电压和 电路。 该特征允许使用比在这样的电路中要求的更小和更便宜的机械开关和PTC装置。 开关和PTC器件的布置也允许PTC器件限制传递到电路的故障电流的大小。

    Frequency-selective circuit protection arrangements
    3.
    发明授权
    Frequency-selective circuit protection arrangements 失效
    频率选择电路保护装置

    公开(公告)号:US06437955B1

    公开(公告)日:2002-08-20

    申请号:US09536905

    申请日:2000-03-28

    IPC分类号: H02H316

    摘要: A conventional ground fault circuit interrupter (GFCI) is modified to provide frequency-selective current protection. A control element is connected in series with the line path (or return path) of the GFCI, and a bypass element is connected in parallel with the combination of the control element and the line path (or return path) of the GFCI. Under normal conditions, little or no current flows through the bypass element. However, frequency response characteristics of the control and/or bypass elements are such that a frequency-selective component of the current (i.e. high-pass, low-pass or band-pass) is diverted through the bypass element. When the magnitude of the frequency-selective component reaches a predetermined value, the bypass current flow causes sensing of a resulting current imbalance and tripping of the GFCI.

    摘要翻译: 传统的接地故障电路断续器(GFCI)被修改以提供频率选择电流保护。 控制元件与GFCI的线路(或返回路径)串联连接,并且旁路元件与控制元件和GFCI的线路径(或返回路径)的组合并联连接。 在正常条件下,很少或没有电流流经旁路元件。 然而,控制和/或旁路元件的频率响应特性使得电流(即,高通,低通或带通)的频率选择分量被转移通过旁路元件。 当频率选择分量的幅度达到预定值时,旁路电流将导致感测到的电流不平衡和GFCI的跳闸。

    Voltage sensing overcurrent protection circuit

    公开(公告)号:US5666254A

    公开(公告)日:1997-09-09

    申请号:US564457

    申请日:1995-11-29

    摘要: An overcurrent protection system which will give a rapid response to overcurrents which cause a reduction in the voltage across the load, e.g. a partial or complete short across the load, and is particularly suitable for protecting circuits against relatively small overcurrents, comprising: a circuit interruption element which, in the operating circuit, is connected in series between the electrical power supply and the electrical load, and which has (1) a closed state which permits the flow of a normal current, I.sub.NORMAL, through the circuit interruption element, and (2) an open state which permits the flow of at most a reduced current, substantially less than I.sub.NORMAL, through the circuit interruption element; a control element which, in the operating circuit, is connected in parallel with the load, and which has (1)(i) an on state, when the voltage across the control element is a normal voltage, V.sub.NORMAL, and (ii) is converted to an off state, when the voltage across the control element falls to a value V.sub.FAULT, or less, and (2) is functionally linked to the circuit interruption element so that when the control element is in the on state, the circuit interruption element is in the closed state, and when the control element is in the off state, the circuit interruption element is in the open state; and a bypass element which (1) is connected in parallel with the circuit interruption element, and (2) has (i) a start-up state such that, if the circuit interruption element is in the fault state and a current I.sub.NORMAL is passed through the bypass element, the voltage across the control element is greater than V.sub.FAULT, and (ii) a stopped state such that if the circuit interruption element is in the fault state as a result of the voltage across the control element having fallen to a value V.sub.FAULT or less, the current through the bypass element is such that the voltage across the control element remains at a value of V.sub.FAULT or less.

    Overcurrent protection circuit
    5.
    发明授权
    Overcurrent protection circuit 失效
    过流保护电路

    公开(公告)号:US5689395A

    公开(公告)日:1997-11-18

    申请号:US564831

    申请日:1995-11-29

    CPC分类号: H02H3/025 H02H9/026

    摘要: An overcurrent protection system which will give a rapid response to relatively small overcurrents. The system, which can be connected between an electrical power supply and an electrical load to form an operating circuit, and which when so connected protects the circuit from overcurrents, has a normal operating condition and a fault condition, and comprises: a circuit interruption element having, (1) a normal state which permits the flow of a normal current, I.sub.NORMAL, when the system is in the normal operating condition, and (2) a fault state which permits the flow of at most a reduced current, substantially less than I.sub.NORMAL, when the system is in the fault condition; and a control element, connected in series with the circuit interruption element, the control element having a variable resistance which (1) is low when the current in the system does not exceed the normal current, I.sub.NORMAL, by a predetermined current amount, and (2) increases by at least a predetermined resistance amount when the current in the system exceeds the normal current, I.sub.NORMAL, by the predetermined current amount; the circuit interruption element changing from its normal state to its fault state, thereby causing the system to change from its normal operating condition to its fault condition, when the resistance of the control element has increased by the predetermined resistance amount.

    摘要翻译: 一种过电流保护系统,能够对相对较小的过电流进行快速响应。 可以连接在电源和电负载之间以形成操作电路的系统,以及当连接保护电路免受过电流时的系统具有正常操作条件和故障状况,并且包括:电路中断元件 具有(1)当系统处于正常操作状态时允许正常电流(INORMAL)流动的正常状态,以及(2)允许至多减少电流流动的故障状态,基本上小于 INORMAL,当系统处于故障状态时; 以及与所述电路中断元件串联连接的控制元件,所述控制元件具有可变电阻(1)当系统中的电流不超过正常电流(INORMAL)预定电流量时(1)为低,并且( 2)当系统中的电流超过正常电流INORMAL预定电流量时,增加至少预定电阻量; 电路中断元件从其正常状态变为其故障状态,从而当控制元件的电阻增加预定电阻量时,使系统从其正常工作状态变为其故障状态。

    Two-terminal transistor PTC circuit protection devices
    6.
    发明授权
    Two-terminal transistor PTC circuit protection devices 有权
    两端晶体管PTC电路保护器件

    公开(公告)号:US06188556B1

    公开(公告)日:2001-02-13

    申请号:US09177666

    申请日:1998-10-22

    IPC分类号: H02H504

    摘要: The present invention provides a two-terminal, transistor-PTC, circuit protection device that has a reduced size and weight and is particularly suitable for use, for example, in portable electronic devices and high density electronic circuits. According to one embodiment of the present invention, a circuit protection device comprises a positive coefficient temperature (PTC) element and a bipolar transistor having base, collector, and emitter terminals. The PTC element is connected between the base and collector terminals of the transistor. The PTC element may be thermally coupled to the transistor and packaged with the transistor as a hybrid device. An electrical load may be connected to the collector terminal of the transistor. According to another embodiment of the present invention, a circuit protection device comprises a PTC element and a Darlington circuit having base, collector and emitter terminals. The PTC element is connected between the base and collector terminals of the Darlington circuit. The PTC element may be thermally coupled to the Darlington circuit and packaged with the Darlington circuit as a hybrid device. An electrical load may be connected to the collector terminal of the Darlington circuit. The Darlington circuit may also be a complementary Darlington circuit.

    摘要翻译: 本发明提供一种具有减小尺寸和重量的双端子晶体管PTC电路保护器件,并且特别适用于例如便携式电子设备和高密度电子电路中。 根据本发明的一个实施例,电路保护装置包括正系数温度(PTC)元件和具有基极,集电极和发射极端子的双极晶体管。 PTC元件连接在晶体管的基极和集电极端子之间。 PTC元件可以热耦合到晶体管并且与晶体管一起作为混合器件封装。 电负载可以连接到晶体管的集电极端子。 根据本发明的另一实施例,电路保护装置包括PTC元件和具有基极,集电极和发射极端子的达林顿电路。 PTC元件连接在达林顿电路的基极和集电极端子之间。 PTC元件可以热耦合到达林顿电路并与达林顿电路一起作为混合器件封装。 电负载可以连接到达林顿电路的集电极端子。 达林顿电路也可以是互补的达林顿电路。

    Electrical switches comprising arrangement of mechanical switches and
PCT device
    7.
    发明授权
    Electrical switches comprising arrangement of mechanical switches and PCT device 失效
    电气开关包括机械开关和PCT装置的布置

    公开(公告)号:US5737160A

    公开(公告)日:1998-04-07

    申请号:US564495

    申请日:1995-11-29

    申请人: Hugh Duffy

    发明人: Hugh Duffy

    摘要: An electrical switch arrangement, comprising a first mechanical switch, a second mechanical switch and a PTC device, with (a) the PTC device and second switch connected in parallel and the parallel combination connected in series with the first switch, or (b) the PTC device and first switch connected in series and the series combination connected in parallel with the second switch. The arrangement can interrupt a current and voltage higher than the rated currents and voltages of each of the switches and the PTC devices. The parallel switch can be rated to interrupt the rated interrupt current of the electrical switch arrangement at a voltage below the rated voltage of the electrical switch arrangement, and the series switch can be rated to interrupt a current below the rated interrupt current of the electrical switch arrangement at the rated voltage of the electrical switch arrangement.

    摘要翻译: 一种电开关装置,包括第一机械开关,第二机械开关和PTC装置,其中(a)并联连接的PTC装置和第二开关以及与第一开关串联连接的并联组合,或(b) PTC器件和第一开关串联连接,串联组合与第二开关并联。 该装置可以中断高于每个开关和PTC装置的额定电流和电压的电流和电压。 并联开关可以额定为在电气开关装置的额定电压以下的电压下中断电气开关装置的额定中断电流,并且串联开关可以额定值中断低于电气开关额定中断电流的电流 在电气开关装置的额定电压下进行布置。

    Transistor-PTC circuit protection devices
    8.
    发明授权
    Transistor-PTC circuit protection devices 失效
    晶体管 - PTC电路保护器件

    公开(公告)号:US06181541B2

    公开(公告)日:2001-01-30

    申请号:US09177795

    申请日:1998-10-22

    IPC分类号: H02H504

    摘要: A circuit protection device for protecting an electrical load includes a three-terminal switch element such as a bipolar, or junction or metal-oxide-semiconductor field effect, transistor and a positive temperature compensation (PTC) resistor. In several embodiments the PTC resistor is in series with the current-carrying electrodes of the transistor. In other embodiments the PTC resistor, or a second PTC resistor, is connected to a control element of the transistor. Both DC and AC load-protection circuits are described.

    摘要翻译: 用于保护电负载的电路保护装置包括诸如双极或结或金属氧化物半导体场效应的三端开关元件,晶体管和正温度补偿(PTC)电阻器。 在几个实施例中,PTC电阻器与晶体管的载流电极串联。 在其他实施例中,PTC电阻器或第二PTC电阻器连接到晶体管的控制元件。 描述直流和交流负载保护电路。

    Electrical heaters
    9.
    发明授权
    Electrical heaters 失效
    电加热器

    公开(公告)号:US4822983A

    公开(公告)日:1989-04-18

    申请号:US938659

    申请日:1986-12-05

    CPC分类号: H05B3/56 H05B3/146

    摘要: Apparatus for automatically disconnecting a conductive polymer heater if an arcing fault occurs. A sensor conductor is incorporated into the heater, so that if an arcing fault occurs, the current through the sensor conductor increases and triggers a safety circuit to disconnect the heater. The sensor conductor is preferably insulated by an organic polymer which pyrolyses if an arcing fault occurs and thus permits current to flow between the sensor conductor and an electrode of the heater.

    摘要翻译: 如果出现电弧故障,则自动断开导电聚合物加热器的装置。 传感器导体被并入到加热器中,使得如果发生电弧故障,则通过传感器导体的电流增加并触发安全电路以断开加热器。 传感器导体优选由有机聚合物绝缘,如果发生电弧故障则热分解,从而允许电流在传感器导体和加热器的电极之间流动。