KR20140143096A

KR20140143096A - Circuit protection device

Info

Publication number: KR20140143096A
Application number: KR1020140066861A
Authority: KR
Inventors: 엘. 모세시안 제리; 데 팔마 장-프랑소와; 에이. 라드짐 마크
Original assignee: 머센 유에스에이 뉴버리포트 - 엠에이, 엘엘씨
Priority date: 2013-06-05
Filing date: 2014-06-02
Publication date: 2014-12-15
Also published as: CA2851850A1; EP2811493A3; CN104242283A; CA2851850C; EP2811493A2; KR101634862B1; JP2014239640A; JP5847236B2

Abstract

SUMMARY OF THE INVENTION The present invention provides a voltage suppression device for voltage surge suppression in a circuit aiding device having a voltage sensitive assembly comprising a plurality of tubular shaped portions inside a tubular casing.

Description

{CIRCUIT PROTECTION DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit protection device, and more particularly, to a device for suppressing a transient current or a transient voltage surge.

BACKGROUND OF THE INVENTION Most of today's highly sensitive electronic products such as computers and computer-related equipment widely used in commercial and residential applications include transient voltage surge suppression (TVSS). These devices protect sensitive or expensive electronic circuits to prevent damage to the electronics from overvoltage failures. These transient voltage surge suppression systems are predicated on reasonable error conditions that are expected in normal use. In this respect, such a system is fabricated to suppress a relatively minor fault condition, but does not protect against a major over-voltage condition. An example of a large overvoltage condition is that the neutral point of the system is lost, ground is lost, or repetitive current pulses are generated by lightning strike. These large overvoltage conditions have a devastating effect on sensitive electronic circuits and components. BACKGROUND ART [0002] Techniques using a larger voltage surge suppression device are known in order to prevent a failure state from being damaged to an electronic circuit and electronic components and electronic equipment. Such a device may be installed in an electrical power transmission line that allows it to flow into the building, or in a power distribution system of a building that controls power surges in the wires that lead to the building, or in a wire to a particular layer of the building. This voltage surge suppressor (TVSS) mainly includes a plurality of metal oxide varistors (hereinafter simply referred to as MOVs) connected in parallel between a service power line and a ground line or a neutral line or connected in parallel between a medium line and a ground line do.

Metal oxide varistors (MOVs) are nonlinear electronic devices fabricated from ceramic-like materials, including zinc oxide particles and complex amorphous inner granular materials. Over a wide range of currents, the voltage typically stays within a narrow band called the varistor voltage. Accordingly, when the relationship between the instantaneous voltage V and the instantaneous current A is expressed by a log-log diagram, it appears as a horizontal line. It is this unique current-voltage characteristic that makes metal oxide varistors (MOVs) an ideal device to protect sensitive electronic circuits from electrical surges, overvoltages, failures, and short circuits.

Upon exposure to a voltage in excess of the voltage of the metal oxide varistor (MOV), the metal oxide varistor (MOV) becomes a highly conductive device that absorbs and dissipates the energy associated with the overvoltage, while at the same time, thereby limiting the dump current. If the overvoltage condition persists, the metal oxide varistor (MOV) will continue to be overheated, resulting in a breakdown or severe failure such as an explosion. Such severe fault conditions can destroy sensitive electronic equipment and electronic components near metal oxide varistors (MOVs). As electronic equipment or electronic components are destroyed in the electrical distribution system, power may not be supplied to the building or the floor for a long time until the corresponding electronic equipment or electronic components are replaced or repaired. Moreover, as metal oxide varistors in the surge suppression system become damaged, the system fails the sensitive electronic equipment that it was designed to protect.

A circuit protection device according to US Pat. No. 6,040,971 proposed by Martenson et al. Discloses a voltage suppression device that protects the arrangement of metal oxide varistors (MOVs) in a surge suppression system. The device could be operated to drop the entire array of metal oxides off-line when the voltage surge reached a certain level. Here, the arranged one or more metal oxides may be severely damaged. In the disclosed apparatus and system, the trigger metal oxide varistor (trigger MOV) is designed to have a lower rated voltage compared to any metal oxide in the array. Thus, if the surge condition exceeds the rated voltage of the trigger metal oxide varistor (trigger MOV), the overall arrangement may drop off-line. In some cases, however, it is desirable to drop off the metal oxide varistor only for the metal oxide varistor that senses a voltage surge that exceeds the rated voltage of the particular metal oxide varistor, while the arranged metal oxide varistor remains operational.

US 6,256,183, which Mosesian et al. Proposes, is a circuit which causes a metal oxide varistor (MOV) in the device to drop off-line when it detects a voltage surge that exceeds the rated voltage of the metal oxide varistor (MOV) Protection device. Both of the above-described devices are designed to be connected between the service line and the ground line or between the neutral line and the ground line.

The present invention provides a circuit protection device and a transient voltage surge suppression system partially included in a tubular casing in order to prevent the electrical system from being catastrophically broken due to excessive overvoltage conditions or repetitive failure conditions along the line .

According to a preferred embodiment of the present invention, there is provided a disposable voltage suppressing device for suppressing voltage surges in an electric circuit. The apparatus comprises a tubular casing made of an electrically insulating material. The first conductor is disposed so as to be attached to the first end of the casing. And the second conductor is disposed so as to stick to the second end of the casing. A voltage sensitive assembly is located within the tubular casing. The voltage sensitive assembly comprises two or more tubular sections. The voltage sensitive assembly has a first surface and a second surface and has a predetermined voltage across across the first surface and the second surface. The voltage sensitive assembly increases in temperature when a voltage applied across the first surface and the second surface exceeds the rated voltage. A first terminal is electrically connected to the first surface of the voltage sensitive assembly and the first conductor. The thermal member is electrically connected to the second surface of the voltage sensitive assembly. The heat member is in a solid state having electrical conductivity at room temperature and has a predetermined softening temperature. And the second terminal is electrically connected to the second conductor. And the second terminal has a connection that is in electrical connection with the second surface of the voltage sensitive assembly. The voltage sensitive assembly senses a voltage drop between the first conductor and the second conductor. Wherein the second terminal is maintained electrically connected to the voltage sensitive assembly by the thermal member and is biased from the voltage sensitive assembly wherein an overvoltage condition sensed by the voltage sensitive assembly is applied to the voltage sensitive assembly When the voltage sensitive assembly is heated beyond the rated voltage and above the softening point of the thermal member, the second terminal is moved in a direction in which the electrical connection with the voltage sensitive assembly is released and disconnects the energizing path. Sensitive assembly, the arc shield moves to a first position to connect the voltage sensitive assembly to the connection of the second terminal when the second terminal moves in a direction to be released from being electrically connected to the voltage sensitive assembly, To a second position located between the connection of the second terminal and the voltage sensitive assembly.

According to another aspect of the present invention, there is provided a voltage suppressing device for suppressing voltage surges in an electric circuit. The device comprises a tubular casing made of an electrically insulating material. The first conductor is disposed so as to be attached to the first end of the casing. And the second conductor is disposed so as to stick to the second end of the casing. Two or more tubular portions are provided. Each tube-shaped portion comprises a voltage sensitive member having a predetermined rated voltage. When a voltage exceeding the rated voltage is applied across the voltage sensitive member, the temperature of the voltage sensitive member rises. Terminals electrically connect the tubular portions disposed between the first conductor and the second conductor. When the thermal switch is normally closed, the thermal switch comprises an end of one of the terminals, a surface of the tubular portions, and a thermal member. The one end of the terminals being maintained in electrical contact with the surface of the tubular members by the thermal member and the thermal switch being capable of electrically connecting any one of the conductors and the tubular portions Sensitive member and the thermal switch is thermally coupled to the tubular portions such that the one of the terminals is electrically connected to the surfaces of the tubular portions Shaped portions of the tubular shaped portions from a normally closed position in which the tubular portions are in contact with the surfaces of the tubular portions when the tubular portions reach a level of softening the thermal member, One of which is moved to an open position to form a gap between the one of the terminals and the tubular portions Move. Said one of said terminals having a connecting portion and a second portion extending away from said connecting portion. When the one of the terminals moves to the open position, the non-conductive barrier operates to move to the gap. The barrier prevents arcing of line voltage surges between the one of the terminals and the tubular portions. The one second portion of the terminals is formed to extend over at least a portion of the non-conductive barrier and is formed to be bent toward the heat member such that the position of the connection portion is maintained until the heat member begins to soften, And is maintained by the heat member. Wherein the non-conductive barrier is in contact with the second portion of the one of the terminals at a location spaced from the connection, wherein a force to move toward the thermal member is applied, It is restricted to move toward the heat member.

According to another aspect of the present invention, there is provided a voltage suppressing device for suppressing voltage surges in an electric circuit. The device comprises a tubular casing made of an electrically insulating material. The device comprises a tubular casing made of an electrically insulating material. The first conductor is attached to the first end of the casing. The second conductor is attached to the second end of the casing. A tubular voltage sensitive assembly is located within the tubular casing. The voltage sensitive assembly includes two or more tubular shaped portions. The voltage sensitive assembly has a first surface and a second surface and has a predetermined voltage across the first surface and the second surface. The voltage sensitive assembly increases in temperature when a voltage applied across the first surface and the second surface exceeds the rated voltage. A first terminal is electrically connected to the first surface of the voltage sensitive assembly and the first conductor. The thermal member is electrically connected to the second surface of the voltage sensitive assembly. The heat member is in a solid state having electrical conductivity at room temperature and has a predetermined softening temperature. The second terminal is formed of a spring metal having an end electrically connected to the second surface of the voltage sensitive assembly and another end connected to the second conductor. The voltage sensitive assembly senses a voltage drop between the first conductor and the second conductor. The second terminal is bent from a normal relaxed configuration such that the thermal member remains connected to the voltage sensitive assembly. The second terminal is intended to be biased away from the voltage sensitive assembly toward the original relaxed state such that the overvoltage condition sensed by the voltage sensitive assembly exceeds a rated voltage of the voltage sensitive assembly, When the heating element is heated above the softening temperature, the second terminal is released from the electrical connection with the voltage sensitive assembly by spring force to soften and break the electrical current path. Sensitive assembly, the arc shield is moved from a first position to connect the second terminal to the voltage sensitive assembly, and the second terminal is connected to the voltage sensitive assembly when the second terminal is moved away from the electrically- Sensitive assembly to a second position located between the voltage sensitive assemblies. And the second terminal includes a connection portion and a second portion for electrically connecting with the thermal member. The second portion extends along the path of the arc shield and limits movement of the arc shield until the thermal member reaches the softening temperature.

The present invention has the advantageous effect of providing a circuit protection device that protects components and systems with sensitive circuitry from current and voltage surges.

Another advantage of the present invention is to provide a circuit protection device as described above capable of preventing the catastrophic damage of a transient voltage surge suppression (TVSS) system in a circuit in which repetitive circuit failures or failure of one excessive portion can occur It is effective.

The present invention has the advantageous effect of providing the aforementioned circuit protection device including the current suppressing device and the voltage suppressing device.

The present invention has another advantage to provide the aforementioned circuit protection device for protecting transient voltage surge suppression systems with metal oxide varistors (MOVs).

The present invention has the advantage of providing a circuit protection device as described above that includes a metal oxide varistor as a circuit breaking device.

The present invention has the advantageous effect of providing the above-described circuit protection device that can be designed in a module form and easily replaced in a circuit line.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other advantageous effects will be apparent from the following description of the preferred embodiments of the present invention with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The invention may be embodied in the form of preferred embodiments, configurations and arrangements of which are illustrated in detail in the Detailed Description and illustrated in the accompanying Drawings.
BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partial cross-sectional front view of a fuse holder having a tubular shape and partially incorporating a circular protector; Fig.
FIG. 2 is a perspective view illustrating a circuit protection device according to an embodiment of the present invention mounted on a DIN-rail fuse holder. FIG.
Figure 3 is a cross-sectional view of the circuit protection device of Figure 2 during normal operating conditions,
Fig. 4 is a sectional view showing the circuit protection device of Fig. 2 after the operation under the failure condition is performed, Fig.
FIG. 5 is an exploded perspective view of the circuit protection device shown in FIG. 2,
Fig. 6 is a cross-sectional view taken along line 5-5 of Fig. 3,
7 is a perspective view of a two-part metal oxide varistor member according to another embodiment of the present invention,
8 is a cross-sectional view of a circuit protection device showing another embodiment of the present invention with an indicator of "tripped"
9 is a sectional view showing the circuit protection device of Fig. 8 in the "tripped state &
10 is an exploded perspective view of a voltage sensitive assembly of a plurality of sections in the form of a tube for use in a circuit protection device according to the present invention,
Figure 11 is an exploded perspective view in accordance with another embodiment of the voltage sensitive assembly shown in Figure 10,
Figure 12 is an exploded perspective view in accordance with another embodiment of the voltage sensitive assembly shown in Figure 10,
Figure 13 is an exploded perspective view in accordance with another embodiment of the voltage sensitive assembly shown in Figure 10,
14 is an exploded perspective view in accordance with another embodiment of a voltage sensitive assembly for a circuit protection device.

The sensitive member (MOV) 52 is located in the casing and has a first surface 52a facing outward and a second surface 52b facing inward. In the embodiment shown in the figures, the voltage sensitive member (MOV) 52 is formed in the shape of a tube. Here, the cylindrical outer circumferential surface of the voltage sensitive member (MOV) 52 forms the first surface 52a and the cylindrical inner circumferential surface of the voltage sensitive member (MOV) 52 forms the second surface 52b. The voltage sensitive member (MOV) 52 is sized to fit within the casing 32. As will be described in greater detail below, the voltage sensitive member (MOV) 52 is formed with an axial length that is slightly smaller than the axial length of the casing 32.

According to the present invention, the voltage sensitive member (MOV) 52 is sensitive to voltage, as its name implies, and the heat is high if the voltage applied across the circuit protection device exceeds a preselected voltage. According to the present invention, the voltage sensitive member (MOV) 52 is preferably formed of a metal oxide varistor.

As in the prior art, metal oxide varistors (MOVs) are formed primarily of granules of zinc oxide sintered together. In the embodiment shown in the figures, the zinc oxide granules are sintered to form a cylindrical tube. Zinc oxide as a solid is a highly conductive material, but a fine air gap or grain boundary is present between sintered zinc oxide granules of a metal oxide varistor (MOV). The boundary between the air gap and the particle suppresses the current from flowing at a low voltage. On the other hand, at high voltages, metal oxide varistors (MOV) become highly conductive parts because the air gaps and boundaries of the metal oxide varistor (MOV) are not wide enough to block the flow of current. However, this conductivity creates very high thermal energy in the metal oxide varistor (MOV). Primarily metal oxide varistors (MOVs) are classified and defined by nominal voltage. The nominal voltage of a metal oxide varistor (MOV), typically defined as V _N ₍ _DC ₎ , is such that the device changes from an off state (i.e., the metal oxide varistor is non-conductive) to operate in a conductive mode . Above all, the nominal voltage is set at 1 mA, and the minimum voltage level (Vmin) and the maximum voltage level (Vmax) are determined by the nominal voltage. In the following, Vmin and Vmax refer to the minimum voltage level and the maximum voltage level, respectively. Looking at one example, not intended to limit the invention, the nominal voltage _{(V N} _(DC)) is 200 volts a metal oxide varistor (MOV) is a minimum voltage level (Vmin) and the maximum voltage level of 228 volts for 184 volts ( Vmax) from the non-conductive state to the conductive state. The above range of operating voltage for a metal oxide varistor having a rated nominal voltage (V _{N (} _DC ₎ ) is due to the properties of the device. In this respect, the actual voltage value of the metal oxide varistor (MOV) basically depends on the thickness of the metal oxide varistor (MOV) and the size and number of zinc oxide granules placed between the two electrode surfaces. At present, due to differences in composition and composition of metal oxide varistors (MOVs), it is absolutely impossible to produce the same device with the same operating characteristics.

Thus, even though the voltage sensitive member MOV 52 of the circuit protection device 10 has a rated nominal voltage V _{N (} _DC ₎ at 1 mA, the metal oxide varistor MOV and other metal oxide varistors MOV) change from the non-conductive state to the conductive state can be varied between the minimum voltage level (Vmin) and the maximum voltage level (Vmax) for the rated nominal voltage value. In view of the present invention, the minimum voltage level (Vmin) of the selected metal oxide varistor (MOV) is important. This will be described later.

A second conductive lining 72 is provided which is in electrical connection with the second surface 52b of the voltage sensitive member (MOV) 52. In the embodiment shown in the figures, the second conductive lining 72 is formed in a tubular shape and is positioned adjacent to the second surface 52b of the voltage sensitive member (MOV) 52 and dimensioned to contact the inner surface . The second conductive lining 72 is dimensioned such that at least a portion of the lining 72 extends along the central portion of the voltage sensitive member (MOV) 52. In the embodiment shown in the figures, the second conductive lining 72 is cylindrical in shape and formed at least as long as the length of the voltage sensitive member (MOV) 52.

A first conductive lining 62 is disposed on the first surface 52a of the voltage sensitive member (MOV) 52. In the embodiment shown in the figures, the first conductive lining 62 is formed in a tubular form and is formed of a conductive material such as a metal. According to a preferred embodiment, the first conductive lining 62 may be formed of copper. In the embodiment shown in the figures, the first conductive lining 62 is formed to have a length substantially equal to the length of the voltage sensitive member (MOV) 52. The first conductive lining 62 is formed to have an inner diameter and dimensioned to substantially coincide with the outer circumferential surface of the voltage sensitive member (MOV) 52. As a result, when the first conductive lining 62 is located on the voltage sensitive member MOV 52, the inner surface of the first conductive lining 62 is connected to the first surface 52a of the electrically sensitive element MOV 52, Electrical connection is made. The first terminal 64 is electrically connected to the first conductive lining 62. In the embodiment shown in the figure, the first terminal 64 is formed in a U-shape. A leg portion 64a of a U-shaped first terminal 64 electrically connected to the first conductive lining 62 and a leg portion 64b extending in parallel to the outer peripheral surface of the casing 32, as shown in Figs. 3 and 4, The first terminal 64 is formed with a dimension wrapping around one end of the casing 32. [ As shown in Figs. 3 and 4, the leg portion 64b is disposed adjacent to the wall surface region 38 formed at the end portion of the casing 32 with a smaller wall thickness. The leg portion 64a of the U-shaped first terminal 64 is formed to bend slightly inward and to be bent toward the other leg portion 64b so that the leg portion 64a is slightly bent Thereby forming a downwardly long base portion 64c.

Referring to FIG. 5, the second terminal 74 includes a base portion 76 and an arm portion 78. In the embodiment shown in the figures, the base portion 76 is flat and shaped like a circular plate, and the arm portion 78 is shaped like an elongated flat rectangular strip. In a normal normal configuration, the arm portion 78 is generally extended in the vertical direction from the base portion 76. The base portion 76 and the arm portion 78 are preferably made of a material such as a plate or sheet having a high rigidity and an electrically conductive property and being flat. In a preferred embodiment, the second terminal (i.e., the base portion 76 and the arm portion 78) is formed of a spring metal or a copper plate. A material such as a plate forming the base portion 76 and the arm portion 78 is made of a material such that the rigidity of the arm portion 78 is high but the free end of the arm portion 78 can be flexurally displaced with respect to the base portion 76 The thickness is determined.

The base portion 76 is formed to have a diameter approximately equal to the diameter of the casing 32. The length of the arm portion 78 is determined so that the free end of the arm portion 78 is located near the axis center of the casing 32 in a state where the circuit protection device 10 is assembled.

As shown in the figure, a bent portion 82 is formed near the free end of the arm portion 78. The bend 82 forms a connection point 82a that is in electrical communication with the inner surface of the second conductive lining 72.

The voltage sensitive member (MOV) 52 is configured such that the outer surface of the second conductive lining 62, as shown in Figures 3 and 4, for the first conductive lining 62 and the second conductive lining 72, Is dimensioned so as to be positioned inside the casing (32) in a state where it is closely fitted to the inner surface of the casing (32). In the embodiment shown in the figures, the voltage sensitive member (MOV) 52 and the first conductive lining 62 and the second conductive lining 72 are formed to have a length slightly smaller than the length of the casing 32. The U-shaped first terminal 64 is formed to have a dimension covering one end of the casing 32. The leg portion 64b of the first terminal 64 at this time extends in the direction along the outer surface of the casing 32 do. The second terminal 74 is formed to have a dimension to be inserted into the other end of the casing 32.

In order to lock the first terminal 64 and the second terminal 74 in the casing 32, end caps 92 and 94 are provided at the ends of the casing 32. Each of the caps 92 and 94 is formed to have a dimension that wraps around one end of the casing 32. In this regard, each end cap 92, 94 is formed in a cup shape and comprises a circular base wall portion 96 and a cylindrical side wall portion 98. The caps 92, 94 are engaged by fitting the open cylindrical sidewall portion 98 into the casing 32. The open ends of the side wall portions 98 of the caps 92 and 94 are configured such that the edges of the free ends of the side wall portions 98 of each of the caps 92 and 94 are connected to the casing 32 and the annular recess 42 formed on the outer surface 36 thereof.

3, the leg portion 64b of the U-shaped second terminal 64 is located between the wall surface area 38 of the casing 32 and the side wall portion 98 of the end cap 92 And is held and fixed. The leg portion 64b of the first terminal 64 is electrically connected to the side wall portion 98 of the end cap 92 made of a metal. In this regard, the end cap 92 is in electrical contact with the first surface 52a of the voltage sensitive member (MOV) 52 through the first terminal 64 and the first conductive lining 62. The first insulating disk 112 is located within the end cap 92. As shown in the figure, the first insulating disk 112 is dimensioned to be disposed on the inner surface of the base wall portion 96. The first insulating disk 112 is formed of an electrically insulating material and is provided to reliably electrically isolate the end cap 92 and the second conductive lining 72 from each other.

(MOV) 52 disposed along the inner surface of the voltage sensitive member (MOV) 52 spaced apart from the end of the casing 32 while firmly fixing the end of the voltage sensitive member (MOV) 52, The base portion 64c of the U-shaped first terminal 64 is formed in an expanded form so as to fix the lining 62 firmly. In other words, in the embodiment shown in the figures, the end of the voltage sensitive member (MOV) 52 and the end of the first conductive lining 62 are spaced from the first insulating disk 112.

The circular base portion 76 of the second terminal 74 is dimensioned to fit within the cap 94 such that the base portion 76 is electrically connected to the base wall portion 96 of the end cap 94, (96).

A second insulating disk 114 formed of an insulating material is provided so as to be positioned inside the end cap 94. The second insulating disk 114 is a flat disk having a circular outer edge that fits inside the end cap 94. The hole 116 is formed at the center of the second insulating disk 114. The hole 116 is dimensioned to such an extent that the arm portion 78 of the second terminal 74 can extend therethrough. In this regard, the second insulating disk 114 is positioned between the end of the casing 32, the end of the voltage sensitive member (MOV) 52, the end of the first conductive lining 62 and the end of the second conductive lining 72 Are arranged adjacent to the end. The second insulating disk 114 substantially isolates the ends of the first conductive lining 64 and the second conductive lining 74 from the base wall 96 of the end cap 94. 3 and 4, the base portion 76 of the second terminal 74 is held between the second insulating disk 114 and the bottom wall portion 96 of the end cap 94 do.

When the second terminal 74 is initially assembled with the casing 32, the arm portion 78 of the second terminal 74 is axially extended in the cavity 34 formed in the casing 32 . As shown in Figs. 3 and 4, the free end of the arm portion 78 of the second terminal 74 is slightly bent to form an offset portion. The arm portion 78 of the second terminal 74 is forced from the first position forcibly being in the normal position (shown in FIG. 4 or the normal relaxed position), and the bent portion 82 formed in the arm portion 78, And is transferred to a second position electrically connected to the inner surface of the conductive lining 72.

According to one embodiment of the present invention, the extended arm portion 78 of the second terminal 74 is in a second position (not shown) that provides electrical connection with the inner surface of the second conductive lining 72 by the heat member 122 3). According to a preferred embodiment, the thermal member 122 may be formed of a solder or solder material having a relatively low softening temperature or melting temperature. A metal alloy (or a ferro-alloy) having a low melting temperature or a polymer having a low softening temperature may be used. The heat member 122 is preferably a solid state at room temperature (25 캜) and a solid state even when the temperature rises to about 35 캜. Preferably, the heat member 122 has a melt temperature or softening temperature between about 70 [deg.] C and 140 [deg.] C, and more preferably between about 90 [deg.] C and 100 [deg.] C.

In one embodiment of the present invention, the heat member 122 is made of about 52% indium (IM) and about 48% tin (SM) and has a melting point of about 118 ° C.

3, in a state in which the arm portion 78 of the second terminal 74 is connected to the second conductive lining 72, the arm portion 78 of the second terminal 74 is resiliently (Different from plastic deformation) so that the arm portion 78 is in contact with the inner wall of the second conductive lining 72. However, when not limited by the heat member 122, the spring is restored to its original normal position as shown in Fig. In other words, the arm portion 78 is formed in a long elongated shape and is formed of a highly rigid metal material and has a spring-like characteristic. 3, a slot or recess 126 is formed between the contact area of the arm portion 78 and the inner surface of the second conductive lining 72, as shown in FIG.

A movable barrier member 132 is provided inside the casing 32. As will be described later, the barrier member 132 is substantially an arc shield. More specifically, the barrier member 132 is movable within the second conductive lining 72. In the embodiment shown in the figures, the barrier member 132 is a cup-shaped member having a generally planar circular base 132a and a cylindrical side wall 132b. Inside the barrier member 132, a cylindrical cavity 132c is formed. The cylindrical side wall 132b of the barrier member 132 is dimensioned so that it can freely slide within an opening formed by the second conductive lining 72. [ Preferably, the barrier member 132 is integrally formed of a non-conductive electrical insulating material. For example, rather than limiting the scope of the present invention, for example, the barrier member 132 may be formed of a polymer. The biasing member 134 exerts a force to deflect the barrier member 132 toward the arm portion 78 of the second terminal 74. The end edge (or front edge) of the sidewall 132b of the barrier member 132 is located on the inner surface of the arm portion 78 when the arm portion 78 is positioned on the inner surface of the second conductive lining 72 by the heat member 122 And the recess or slot 126 formed by the surface of the second conductive lining 72. [0064] As shown in Fig. In the embodiment shown in the drawing, the biasing member 134 is a compression spring. The dimensions of the arm portion 78 and the barrier member 132 and the compression spring 134 are such that the free end of the arm portion 78 contacts the inner wall of the second conductive lining 72, Is prevented from moving relative to the arm portion 78 by the bent portion 82 of the arm portion 78 in the second conductive lining 72. 3, the compression spring 132 exerts a biasing force on the base 132a of the cup-shaped barrier 132 which is disturbed by the bend 82 of the arm portion 78 .

As for the operation of the circuit protection device 10, one or more circuit protection devices 10 may be used to protect the electrical circuitry together against the circuit failure conditions. In the case where the circuit protection device 10 is used in a general DIN-rail fuse mount 20 as shown in Fig. 2, the circuit protection device 10 in the fuse holder 12, as shown in Fig. 1, Is preferably used. The individual can easily connect the circuit protection device 10 to the electrical system or the circuit to be protected through the fuse holder 12 without being electrically exposed to the transmission line. In other words, the fuse holder 12 allows easy and safe installation and disconnection of circuit protection devices to "live" circuits.

The caps 92 and 94 of the circuit protection device 10 are connected to the connection blades 24 of the holder 12 when the circuit protection device 10 is disposed in the holder 12 and the fuse holder 12 is in the closed position ). A circuit path is created through the circuit protection device 10 when the fuse holder 12 is coupled across the transmission line of the electrical circuit and the ground and neutral wires. More specifically, the circuit path is formed by a path from the cap 92 to the second conductive lining 62 and through the voltage sensitive member (MOV) 52 to the first conductive lining 72. The circuit path extends from the second conductive lining 72 through the arm portion 78 of the second terminal 74 (which is connected to the second conductive lining 72 by the thermal member 122) 94). In other words, when the fuse holder 12 is located on the mounting rail (not shown) and the circuit protection device 10 is electrically connected to the connection blade 24, the conductive path is between the transmission line and the ground line or the neutral line Is formed through the circuit protection device (10). Even if the positions of the end caps 92, 94 are inverted with respect to each other, the conductive path is set to pass through the circuit protection device 10.

As described above, one or more circuit protection devices may be used to protect the electrical circuitry. The circuit protection system may comprise N circuit protection devices 10 connected in parallel with transmission lines and ground lines or neutral lines. In such a "multi-device system", and the circuit protection device 10 has the same rated "nominal voltage (V _{N (DC))"} and the peak surge current rating (rating). The total amount of current surge protection provided by such a multiple device system is approximately N times the peak current surge of the circuit protection device 10 used in the system. For example, if each circuit protection device 10 has a peak current surge rating of 10,000 A (amps), then the total amount of current surge protection of the assembly is (10,000 * N) A (amps). As noted above, even though each circuit protection device 10 has the same "rated nominal voltage ",the" rated nominal voltage "of each MOV in circuit protection device 100 is the minimum voltage level Vmin and the maximum voltage level Vmax) of the circuit protection device 10. As a result, the current surge experienced by each circuit protection device 10 may not be generated at the same time as described later.

In the case of an overvoltage condition or a repetitive pulse condition, the voltage sensitive member (MOV) 52 of the circuit protection device 10 will experience an overvoltage condition. This overvoltage condition causes a voltage difference across the first surface 52a and the second surface 52b of the voltage sensitive member MOV 52 between the first conductive lining 62 and the second conductive lining 72, (Bias) is generated. When a voltage deviation occurs, thermal energy is generated by the surge current, and each tube-shaped voltage sensitive member (MOV) 52 absorbs the energy and dissipates the absorbed energy into heat. As the voltage deviation of the voltage sensitive member (MOV) 52 increases, the electrical conductivity of the voltage sensitive member (MOV) 52 rises and accordingly as much heat is generated. As described above, since the actual characteristics of each voltage sensitive member (MOV) 52 are not identical, the voltage-sensitive member (MOV) 52 arranged in series has a lower energy rating, . Thus, the various voltage sensitive elements (MOV) 52 will be heated faster in the multi-device system as compared to the other voltage sensitive elements (MOV) 52. If the failure condition is severe enough, the voltage sensitive member (MOV) 52 of the one or more circuit protection devices 10 is heated to reach the melting temperature of the low temperature solder material of the thermal member 122. When the melting temperature of the low temperature solder material is reached, the arm portion 78 of the second terminal 74 is no longer held in the first position (shown in Fig. 3). When the heat member 122 is melted, the metallic material forming the second terminal 74 tries to return to the normal planar shape due to the elastic restoring force, which is the mechanical force inside the second terminal 74, 78 are freed from the inner surface 52a of the voltage sensitive member (MOV) 52 without restraint.

According to an aspect of the invention, the second surface (inner surface, 52b) of the voltage sensitive member (MOV) 52 is heated faster than the first surface (outer surface, 52a). This is because the second surface 52b is smaller in diameter than the first surface 52a and has a smaller surface area. Due to the smaller surface area, the current density per unit area is consequently higher than joule heat per unit area along the second surface 52b compared to along the first surface 52a. As the second surface 52b is heated faster, the thermal member 122 can be melted under fault conditions.

When the arm portion 78 is moved away from the voltage sensitive member (MOV) 52, the conductive path through the circuit protection device 10 is broken and the circuit protection device 10 becomes "offline ".

When one circuit protection device 10 becomes "off-line ", the current surge rating of the other circuit protection devices 10 in the multiple device system is reduced. Using the above example, when one current protection device 10 becomes "off-line ", the system loses the surge ability of 10,000 A (amps), but when replacing the circuit protection device 10 in the off- , The current surge rating of (10,000 * (N-1)) A (amps) is still held.

Thus, the present invention provides a circuit protection device 10 that may be used as a unit and form part of a circuit protection system to be used with other devices. If the voltage spike seriously exceeds the rated nominal voltage of the circuit protection device 10, then the circuit protection device 10 is able to suppress voltage spikes in the circuit and lower it to an off-line state to prevent fatal damage of the device It is a stand-alone unit.

8 and 9, a circuit protection device 210 according to another embodiment of the present invention is shown. The circuit protection device 210 is the same in many respects as the circuit protection device 10 described above. In this respect, the components of the circuit protection device 210 similar to those of the circuit protection device 10 are given the same reference numerals. The circuit protection device 210 according to the present embodiment is different from the circuit protection device 10 described above in that the pin 232 extending long in the axial direction is provided from the flat circular base 132a of the cylindrical barrier member 132, . 8, when the barrier member 132 is held in the first position with respect to the biasing member 134 by the arm portion 78 of the second terminal 74, the first insulating disk 112 And an opening 234 formed through the base wall 96 of the end cap 92. The pin 234 of the end cap 92 is connected to the base end of the end cap 92, 8, the end 232a of the pin 232 is connected to the base wall 96 of the end cap 92 when the circuit protection device 210 is in its normal operating configuration. . As the deflection member 134 forces the barrier member 132 to the "trip position" when a failure condition that causes the circuit protection device 210 to "tripped" And the inner wall 232a of the casing 32 is retracted into the inner hole 34 of the casing 32. Therefore, whether the circuit protection device 210 is in the " tripped state "or not can be determined depending on whether or not the end portion 232a of the pin 232 extends out of the end cap 92. [ Accordingly, the circuit protection device 210 can quickly grasp the state even with a simple configuration by an indicator that makes it easy to know the state.

It should be noted that the detailed description of the invention described above is intended to illustrate certain embodiments of the invention, and that there are numerous modified embodiments by those of ordinary skill in the art to which the present invention pertains. For example, the configuration of a voltage sensitive member (MOV) 52 made of one piece has been described in the embodiment. However, instead of the voltage sensitive member (MOV) 52 in the circuit protection device 10, a voltage sensitive member 152 consisting of the two divided parts 154 and 156 shown in Fig. 7 may be used. The first conductive lining 62 and the second conductive lining 72 are formed in the desired tubular shape within the circuit protection device 10 such that each of these portions 154, 156 can be positioned.

Previously, the circuit protection device 10 described a configuration with a voltage sensitive member 152 comprised of one elongated tubular member or two semi-cylindrical portions 154, 156. In accordance with another aspect of the present invention, Figures 10-14 illustrate an alternative embodiment of a circuit protection device 10, represented by reference numerals 252, 252A, 252B, 252C, and 352, Sensitive assembly of N short tube-shaped varistor parts, which can be used.

Figure 10 shows a voltage sensitive assembly 252 comprised of short tubular sections 262, 264, 266, 268 (tubular sections). In the embodiment shown in the figures, the tubular portions 262, 264, 266, 268 are formed to have essentially the same or similar inner and outer diameters. Each tube-shaped portion 262, 264, 266, 268 is made of the same or similar varistor material. 10, the voltage sensitive component in the circuit protection device 10 may be comprised of two or more tubular portions 262, 264, 266, 268. [ In this regard, the formation of a plurality of elongated voltage sensitive members 52 of the shorter tubular shaped portions 262, 264, 266, 268 results in the formation of a voltage sensitive member 52 It is easier and more economical than doing it. Moreover, according to another aspect of the disclosed embodiments, by fabricating the voltage sensitive assembly 252 with a plurality of short tubular portions 262, 264, 266, 268, It becomes possible to produce the voltage suppressing device 10 having different operating characteristics. All of the tubular portions 262, 264, 266, 268, 268, 264, 262, 264, 262, 264, 262, The operation characteristics of the circuit protection device 10 can be simply changed. For example, by removing one tube-shaped portion, the amount of metal oxide varistor (MOV) material in the circuit protection device 10 is reduced by 25%. Thus, the operating characteristics of the circuit protection device 10 are reduced in accordance with the amount of metal oxide varistor (MOV) material from which the tubular portion 268 is removed.

FIG. 11 shows a voltage sensitive assembly 252A that changes the voltage sensitive assembly 252 of FIG. The voltage sensitive assembly 252A of Figure 11 is essentially the same as the voltage sensitive member 252 of Figure 10 except that the tubular portion 266 is replaced with a tubular nonconductive insulator 276 . The non-conductive insulator 276 is formed to have the same dimensions as the tubular portion 266.

The non-conductive insulator 276 is inserted into the location of the tubular portion 266 to maintain the overall structural form of the circuit-protector 10. Since the inner circumferential surface and the outer circumferential surface of the portions of the tubular portions 262, 264 and 268 respectively contact the inner circumferential surface of the first conductive lining 62 and the outer circumferential surface of the second conductive lining 72, May be in any position within the space defined between the first conductive lining 62 and the second conductive lining 72. [ In other words, the non-conductive insulator 276 may be located at the end of the tubular portions 262, 264, 268 and may be located at 262 May be located between the portion of the tube shape shown and the portion of the tube shape indicated by reference numeral 264 and may be located between the portion of the tube shape indicated by reference numeral 264 and the portion of the tube shape indicated by reference numeral 268 You may.

Referring to FIG. 12, another variation of voltage sensitive assembly 252 is shown. The voltage sensitive assembly 252B shown in Figure 12 is similar to the voltage sensitive assembly 252B in that the tubular portion 264 of the voltage sensitive assembly 252 of Figure 10 is a varistor material that forms tubular portions 262, 266, Sensitive assembly 252 of FIG. 10, except that a portion 284 of tubular shape made of another metal oxide varistor (MOV) material is substituted. By varying the components of one or more tubular portions within the circuit protection device 10, the overall operating characteristics of the voltage sensitive assembly 252B can be varied.

By just changing the number and / or type of tubular portions 262, 264, 266, 268 disposed in the circuit protection device 10 from the foregoing, the operating characteristics of the circuit protection device 10 And how it can be changed.

As will be appreciated by those skilled in the art, the respective dimensions of the tubular portions 262, 264, 266, 268 (i.e., the volume and mass of the material forming these portions) Determine the operating characteristics of the parts. Figure 13 illustrates that the dimensions of the tubular part can additionally affect the changing operating conditions of the tubular part. A voltage sensitive assembly 252C having a tubular portion 294 with an inner portion 294a made of a varistor material and an outer portion 294b made of a conductive material is shown in FIG. As shown in the figure, the medial portion 294a of the tubular portion 294 is tubular in shape and has a smaller wall thickness than the tubular portions 262, 264, 266, 268 described above Dimension. The outer portion 296b is tubular in shape and dimensioned to maintain electrical contact with the inner circumferential surface of the first conductive lining 62 of the current protection device 10. [ Shaped portion 294 having a conductive outer portion 294b and a tubular inner portion 294a formed of a varistor material is provided so that the operating characteristics of the voltage and current of the tubular portion 294 are controlled by the metal oxide varistor Shaped portions 262, 264, 266 and 268 made of only MOV material.

13, a tubular portion 296 having a tubular portion 296 having an inner portion 296a made of a conductive material and an outer portion 296b made of a metal oxide varistor (MOV) .

In this respect, when formed of different materials, they cause differences in the ability to deliver voltage and current in the tubular portion. The above-described circuit protection device 10 may use a tubular part made of a material similar to a varistor or a tubular part made of another material.

14 shows a voltage sensitive assembly 352 of cylindrical tube shaped portions 362, 364, 366, 368 as another embodiment of the present invention. The tubular portions 362, 364, 366, and 368 are all formed to have the same or similar inner and outer diameters, while the axial lengths of the tubular portions 366 and 368 are different, and reference numerals 362, Which is also different from the axial length of the tubular portions designated 364. Figure 14 illustrates how tubular portions of different lengths may be used to form a voltage sensitive assembly in accordance with the present invention. As discussed above with respect to the voltage sensitive assembly 252A, one or more tubular portions may be removed or replaced with tubular insulators to alter the operating characteristics of the voltage sensitive assembly within the circuit protection device 10. It will be apparent to those skilled in the art that different components may be combined from the voltage sensitive assembly disclosed in Figures 10-14 in accordance with the present invention.

All such modifications as are contemplated are within the scope of the claims or equivalents of the claims of the present invention.

10: circuit protection device 12: fuse holder
32: casing 34: cavity
38: wall area 52: voltage sensitive member (MOV)
62: first conductive lining 64: first terminal
72: second conductive lining 74: second terminal
76: base portion 78: arm portion
92, 94: end cap 122: heat member
132: barrier member 134: biasing member
252, 252A, 252B: voltage sensitive assembly

Claims

A tubular casing made of an electrically insulating material;
A first conductor disposed on a first end of the casing;
A second conductor disposed on a second end of the casing;
A first surface and a second surface, said tubular casing having at least two tubular sections, said tubular casing having a first surface and a second surface, A voltage sensitive assembly having a rated voltage and rising in temperature when a voltage applied across the first surface and the second surface exceeds the rated voltage;
A first terminal electrically connected to the first surface of the voltage sensitive assembly and the first conductor;
A thermal element electrically connected to the second surface of the voltage sensitive assembly and having an electrically conductive solid state at room temperature and having a predetermined softening temperature;
A second terminal electrically connected to the second conductor and having a connection portion electrically connected to the second surface of the voltage sensitive assembly;
Sensitive assembly senses a voltage drop between the first conductor and the second conductor and the second terminal remains electrically connected to the voltage sensitive assembly by the thermal member Sensitive assembly, wherein when the overvoltage condition sensed by the voltage sensitive assembly exceeds a rated voltage of the voltage sensitive assembly and the voltage sensitive assembly is heated to a temperature above the softening point of the thermal member, Sensitive assembly moves in a direction in which the electrical connection with the voltage sensitive assembly is released, thereby disconnecting the energizing path,
Sensitive assembly, the voltage-sensitive assembly comprising: a first terminal for connecting the connection of the second terminal to the voltage sensitive assembly when the second terminal moves from a state of being electrically connected to the voltage sensitive assembly; An arc shield movable to a second position located between the sensitive assemblies;
Voltage-surge-suppressing device for suppressing voltage surges in an electric circuit.

The method according to claim 1,
Wherein the voltage sensitive assembly comprises a plurality of tubular metal oxide varistors (MOVs).

The method according to claim 1,
Wherein the tubular portions of the voltage sensitive assembly are of the same shape.

The method according to claim 1,
Wherein the tubular portions of the voltage sensitive assembly are formed with the same dimensions.

The method according to claim 1,
Wherein at least one of the tubular portions of the voltage sensitive assembly is formed in a different dimension.

The method according to claim 1,
Wherein the tubular portions of the voltage sensitive assembly are formed of the same material.

The method according to claim 1,
Wherein at least one of the tubular portions comprises a medial side and an outer side.

8. The method of claim 7,
Wherein at least one of the inner portions of the tube-shaped portions is formed of a metal oxide varistor material, and at least one of the outer portions of the tube-shaped portions is formed of an electrically conductive material.

8. The method of claim 7,
Wherein at least one of the outer portions of the tubular portions is formed of a metal oxide varistor material and at least one of the inner portions of the tubular portions is formed of an electrically conductive material.

8. The method of claim 7,
Wherein at least one of said medial and lateral portions of said tubular portions is tubular in shape.

The method according to claim 1,
Wherein the tube-shaped portions are disposed adjacent to each other in mutual contact in the tubular casing.

The method according to claim 1,
Wherein the tubular portions are spaced apart from each other in the tubular casing.

13. The method of claim 12,
Characterized in that a non-conductive insulator is interposed between said tubular portions spaced apart from each other.

A tubular casing made of an electrically insulating material;
A first conductor disposed on a first end of the casing;
A second conductor disposed on a second end of the casing;
Two or more tubular shaped portions each having a predetermined rated voltage and each made of a voltage sensitive member whose temperature rises when a voltage exceeding the rated voltage is applied;
Terminals for electrical connection with the tubular portions disposed between the first conductor and the second conductor;
A thermostat comprising a tip in the normally closed state, an end of one of the terminals, a surface of the tubular portions, and a thermal member;
Wherein one end of the terminals is held in electrical contact with the surface of the tubular portions by the thermal member, and the thermal switch is configured such that one of the conductors and the tube- Wherein said heat switch is thermally coupled to said tubular portions such that said one of said terminals is in electrical contact with said surface of said tubular portions Shaped portions of the tubular shaped portions from a normally closed position where the tubular shaped portions are maintained in an electrically connected state when the tubular shaped portions reach a level of softening the thermal member, The one of the terminals moving to form a gap between the one of the terminals and the tubular portions A room location, the movement of said one terminal, and;
Said one of said terminals having a connection portion and a second portion extending away from said connection portion;
A non-conductive barrier operative to move to said gap when said one of said terminals moves to an open position and to prevent arcing of line voltage surges between said one of said terminals and said tubular portions ;
Further included,
The one second portion of the terminals being formed extending over at least a portion of the non-conductive barrier and being bent toward the heat member such that the position of the connection portion is substantially parallel to the heat Is maintained by a member;
Wherein the non-conductive barrier is in contact with the second portion of the one of the terminals at a position spaced apart from the connecting portion while a force to move toward the heating element is applied, until the heating element is softened Wherein the movement of the heating member toward the heating member is limited.

15. The method of claim 14,
Wherein the thermal switch has a terminal held in electrical connection with the tubular portions by the thermal member, the terminal moving away from the tubular portions.

16. The method of claim 15,
Wherein the thermal member is a solder material having a low melting temperature.

15. The method of claim 14,
Wherein the tubular portions are made of a metal oxide varistor (MOV) material.

15. The method of claim 14,
Wherein the tubular portions are of the same shape.

The method according to claim 1,
Wherein the tube-shaped portions are formed to have the same dimensions.

15. The method of claim 14,
Wherein at least one of the tubular portions is formed in a different dimension.

15. The method of claim 14,
Wherein the tube-shaped portions are formed of the same material.

15. The method of claim 14,
Wherein at least one of the tubular portions comprises a medial side and an outer side.

23. The method of claim 22,
Wherein at least one of the inner portions of the tube-shaped portions is formed of a metal oxide varistor material, and at least one of the outer portions of the tube-shaped portions is formed of an electrically conductive material.

23. The method of claim 22,
Wherein at least one of the outer portions of the tubular portions is formed of a metal oxide varistor material and at least one of the inner portions of the tubular portions is formed of an electrically conductive material.

23. The method of claim 22,
Wherein at least one of said medial and lateral portions of said tubular portions is tubular in shape.

15. The method of claim 14,
Wherein the tube-shaped portions are disposed adjacent to each other in mutual contact in the tubular casing.

15. The method of claim 14,
Wherein the tubular portions are spaced apart from each other in the tubular casing.

28. The method of claim 27,
Characterized in that a non-conductive insulator is interposed between said tubular portions spaced apart from each other.

A tubular casing made of an electrically insulating material;
A first conductor disposed on a first end of the casing;
A second conductor disposed on a second end of the casing;
A tubular casing having a first surface and a second surface, wherein the tubular casing comprises tubular sections of at least two tubular sections, said tubular sections having a first surface and a second surface, A voltage sensitive assembly having a predetermined rated voltage and having a temperature rising when a voltage applied across the first surface and the second surface exceeds the rated voltage;
A first terminal electrically connected to the first surface of the voltage sensitive assembly and the first conductor;
A thermal element electrically connected to the second surface of the voltage sensitive assembly and having an electrically conductive solid state at room temperature and having a predetermined softening temperature;
A second terminal formed of a spring metal having an end electrically connected to the second surface of the voltage sensitive assembly and another end connected to the second conductor;
Sensitive assembly senses a voltage drop between the first conductor and the second conductor and the second terminal is bent from a normal relaxed configuration, Sensitive assembly and the second terminal is intended to be deflected away from the voltage sensitive assembly to the normal relaxed state so that an overvoltage condition sensed by the voltage sensitive assembly is sensed by the voltage sensitive assembly, Sensitive assembly, when the voltage sensitive assembly heats the thermal member above the softening temperature, the second terminal is released from the electrical connection with the voltage sensitive assembly to be softened by spring force, Disconnect the current path,
Sensitive assembly, said second terminal and said voltage sensitive assembly, when said second terminal and said voltage sensitive assembly move from a state of being electrically disconnected from said voltage sensitive assembly, And an arc shield movable between a first position and a second position,
Wherein the second terminal includes a connection portion and a second portion for electrically connecting to the thermal member and the second portion extends along a path of the arc shield portion, And the movement of the arc shielding portion is restricted.