Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
  • H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
  • H02H9/042—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage comprising means to limit the absorbed power or indicate damaged over-voltage protection device
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01C—RESISTORS
  • H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
  • H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
  • H01C7/12—Overvoltage protection resistors
  • H01C7/126—Means for protecting against excessive pressure or for disconnecting in case of failure
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/0201—Thermal arrangements, e.g. for cooling, heating or preventing overheating
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/0213—Electrical arrangements not otherwise provided for
  • H05K1/0254—High voltage adaptations; Electrical insulation details; Overvoltage or electrostatic discharge protection ; Arrangements for regulating voltages or for using plural voltages
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/09—Shape and layout
  • H05K2201/09009—Substrate related
  • H05K2201/09063—Holes or slots in insulating substrate not used for electrical connections
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
  • H05K2201/10007—Types of components
  • H05K2201/10022—Non-printed resistor
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
  • H05K2201/10007—Types of components
  • H05K2201/10181—Fuse
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
  • H05K2201/10227—Other objects, e.g. metallic pieces
  • H05K2201/1028—Thin metal strips as connectors or conductors
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/02—Details related to mechanical or acoustic processing, e.g. drilling, punching, cutting, using ultrasound
  • H05K2203/0271—Mechanical force other than pressure, e.g. shearing or pulling
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/17—Post-manufacturing processes
  • H05K2203/176—Removing, replacing or disconnecting component; Easily removable component

Definitions

• the invention relates to a device for overvoltage protection containing between the pair of connection points L/N and N/L being connected at least one varistor, which is through the thermal activation disconnectable from the protected electrical circuit, while between the pair of connection points L/N,
• the device further incorporates a basic board created as a printed circuit and containing electrically conductive layer forming at least a part of conductive connections between individual elements of the device.
• the device for overvoltage protection of the D class serves for protection of power consumers connected to the terminal equipment of electric current distribution against destructive effects of overvoltage acting upon these consumers.
• overvoltage spreads through the distributions of electric current and it is able to damage or totally destroy the connected power consumers, while the vicinity of these power consumers may be damaged, e.g. by fire or explosion caused by damage or destroy of the respective power consumer.
• the known devices for overvoltage protection of the D class contain at least one varistor, which at normal conditions does not conduct electric current, nevertheless upon voltage increase above the specified limit (overvoltage) it already conducts electric current, through which the overvoltage is limited. Nevertheless upon elimination of overvoltage the varistor is heated up, which deteriorates the same, so varistor may due to abnormal loading let through always increasing electric current even at normal operation conditions, or it may be totally destroyed and varistor does not fulfil its function at all, even it may damage the system of overvoltage protection. Therefore it is necessary upon varistor overheating to secure that varistor is disconnected from the protected electric circuit. This disconnection is being done in various manners, while the used manners of disconnection exhibit various features in dependence on their structural solution.
• the thermal disconnecting device of varistor which contains a pair of parallel side by side positioned varistors, between which there is situated a flat element provided on both its ends with one springy arm.
• This one arm is soldered to one outlet of the first varistor on one side of the equipment for overvoltage protection and the second arm is soldered to one outlet of the second varistor on the other side of the device for overvoltage protection.
• the flat element Upon occurrence of overvoltage by electric current passing through one of varistors the flat element warms up and due to this the low-fusing soldered joints of springy arms and of the cross-wise situated varistor outlets are melted, so that the springy arms are released and press on the switch, which disconnects the varistors from the protected electrical circuit.
• the whole device is placed in a plastic bushing.
• the disadvantage of this embodiment is a relatively great thickness of the device, which limits its applicability in narrow slots of terminal equipment of electric distributions, electric sockets or small wiring boxes of intermediate adaptors.
• One outlet of the first varistor and with it neighbouring one outlet of the second varistor are hereby by means of low-fusing soldered joints connected with a breaking-off body, through which they are interconnected.
• the breaking-off body is by means of a link which is heat resistant coupled with the put off means.
• the breaking-off body is by means of an electrically conductive joint, which is heat resistant and enables the breaking- off movement of the breaking-off body connected with one outlet of the aerial discharge.
• the breaking-off body is in the particular example embodiment formed by a flat metal body and it possibly contains also a calibration element situated in the direction of breaking-off movement of the breaking-off body on its backside in the area passing between both neighbouring outlets of varistors being broken-off.
• the put off means is by example formed by a spring which is by one its end positioned on the breaking-off body and by its second end it is positioned in the structure of the device.
• Electric conductive joint which is heat resistant and enables the breaking-off movement of the breaking-off body is by example formed by a flexible electric conductor, e.g. by a copper wire.
• Neighbouring outlets of a pair of varistors connected by means of a low-fusing soldered joint with the breaking-off body are in the place in which they are connected to the breaking-off body provided at least with one at least partial bending situated in the plane of the breaking-off body.
• the disadvantage of this arrangement is a relatively high complexity and the related high work difficulty which result in a relatively high production costs.
• the aim of this invention is to reduce the complexity, work difficulty and a costly acquisition of the device for overvoltage protection.
• the device for overvoltage protection whose principle consists in that the varistor is with its one contact attached to the electrically conductive layer of the basic board and in the vicinity of connection place of varistor outlet to electrically conductive layer of the basic board to the electrically conductive layer of the basic board by means of low-fusing joint is attached the electrically conductive breaking-off body, which is by means of electrically conductive heat resistant link connected to one outlet of the aerial discharge and is coupled with the put off means.
• This arrangement markedly reduces complexity and the related work difficulty of the device and it contributes to decrease in costs while the functions and reliability are preserved.
• each varistor at least with its one outlet is attached to the electrically conductive layer of the basic board, at the same time between one outlet of the first varistor and one outlet of the second varistor there is electrically conductive layer of the basic board interrupted, and in the vicinity of place of connection of outlet of the first varistor and outlet of the second varistor to electrically conductive layer of the basic board is to electrically conductive layer of the basic board by means of low-fusing joints attached the electrically conductive, breaking-off body, which is by an electrically conductive heat resistant link connected to one outlet of the aerial discharge and is coupled with the put off means.
• the electric conductive heat resistant link of the breaking-off body with one outlet of the aerial discharge designed as an essential part of the breaking-off body.
• the put off means is formed by an extension spring, which is by its one end positioned on breaking off means and by its second end it is coupled with the basic board.
• the invention is schematically illustrated in the drawing where the Fig. 1 shows wiring diagram of the device for overvoltage protection according to the invention, the Fig. 2 schematic arrangement of the joint for thermal disconnection of a pair of varistors from the protected circuit at device embodiment with a pair of varistors and the Fig. 3 schematic arrangement of the joint for thermal disconnection of varistor from the protected circuit at the device embodiment with one varistor.
• the device for overvoltage protection contains between a pair of connection points UN and N/L in series connected system of pair of varistors V1, V2 and a common thermal disconnecting device 1 of both varistors VM 1 V2, which disconnects both two varistors at the same time from the protected electrical circuit and which is in the circuit inserted between the both varistors VI, V2.
• L shows the connection point to the phase conductor of the terminal equipment of electric distribution network, e.g. of electric socket, N connection point to zero conductor of the terminal equipment of electric distribution network e.g. of electric socket and PE connection point for grounding of terminal equipment of electric distribution network, e.g. of electric socket.
• connection points L, N, PE the corresponding elements of equipment need not to be, and as a rule they are not, connected directly, but they are coupled with them via further elements of the device for overvoltage protection.
• the device for overvoltage protection contains the basic board 4, which contains electrically conductive layer, which by means of technique of printed circuits creates at least one section of individual electrical interconnection of corresponding elements of the device for overvoltage protection.
• Both varistors Vl, V2 are situated side by side. In the illustrated example of embodiment both varistor VJ-, V2 are situated in one plane. At the same time the varistors VI 1 V2 may be situated in the plane parallel with the basic board 4 or in the plane perpendicular to the basic board 4 or in the plane askew to the basic board 4.
• varistors VI, V2 are situated in various planes, which may be parallel, perpendicular or askew towards the basic board 4 , or mutually one to another, while both varistors VI, V2 overlap partially or totally, or they do not overlap at all.
• the particular shape execution and space arrangement of individual parts of the thermal disconnecting device 1 is adapted to individual mutual arrangement of both varistors VI , V2 .
• Each varistor VI, V2 contains a pair of outlets. Two neighbouring outlets Kl, K2 of the varistors VI, V2, i.e. from one varistor VJ. one outlet Kl and to this outlet Kl an adjoining one outlet K2 from the second varistor V2, are connected directly to the electrically conductive layer of the basic board 4. Between the outlet Kl of one varistor VJ. and the outlet K2 of the second varistor V2 the basic board 4 is provided with an insulation interruption of its electrically conductive layer between the outlet KJ. of one varistor VJ. and the outlet K2 of the second varistor V2. In the illustrated example of embodiment the interruption of electrically conductive layer of the basic board 4 is performed by means of a groove 40 , which may be even continuous through the basic board 4.
• aerial discharge 2 In the illustrated example of embodiment only one aerial discharge 2 is used. In the not illustrated example of embodiment instead of a single aerial discharge 2 other functionally identical means are used, e.g. created by a more complex circuit solution with several aerial discharges as it is known e.g. from the CZ patent No. 292 593. Therefore in this context in the whole text and in the patent claims under the term ,,aerial discharge" the aerial discharge itself is understood as an independent part, as well as any device fulfilling the same or an equivalent function.
• the breaking-off body 6 is with outlet of aerial discharge 2 coupled by means of heat resistant arm, which is an essential part of the breaking-off body 6, i.e. it is produced already during production of the breaking-off body 6, and which is at the side of the aerial discharge 2 connected with electrically conductive layer of the basic board 2, to which at the same time the outlet of the aerial discharge 2 is connected.
• the arm electrically connecting the breaking-off body 6 with outlet of the aerial discharge 2 is deformable sufficiently, so that it enables breaking-off movement of the breaking-off body 6 and also so that it is possible together with the breaking-off body 6 to adjust it for various modifications of particular illustrated and described arrangements of device for the overvoltage protection.
• the breaking-off body 6 is with outlet of aerial discharge 2 coupled by means of heat resistant arm, which is an essential part of the breaking-off body 6, i.e. it is produced already during production of the breaking-off body 6, and which is at the side of the aerial discharge 2 connected with electrically conductive layer of the basic board 2, to which at the same time the outlet of the
• a flexible electrical conductor e.g. copper wire conductor etc. which is by its one end by means of a heat resistant link connected with the breaking-off body 6 and with its second end it is connected with outlet of the aerial discharge 2.
• the breaking-off body 6 is coupled with the put off means 9 for putting off the breaking-off body 6 from the place of connection of its ends 60, 61 to electrically conductive layer of the basic board 4 and outlet Kl of varistor Yl and outlet K2 of varistor V2 after the low-fusing soldered joints 5, 7 loose their rigidity.
• the put off means 9 is connected with the breaking-off body 6 by means of a heat resistant link.
• the breaking-off body 6 is formed by an oblong thin metal body made of electrically conductive material, from whose one end 60 extends the heat resistant arm connected with its second end to one outlet of the aerial discharge 2, at the same time in the middle section of length of the breaking-off body 6 to the breaking-off body 6 there is attached one end of the put off means 9, while the second end of the put off means 9 is positioned on the basic board 4.
• the breaking-off body 6 may alternatively be formed by a body of another suitable shape, e.g. it may be of a triangle or square or some other suitable shape.
• the put off means 9 is formed by an extension spring, which is by its one end hooked on the middle section of the breaking-off body 6 and by its second end it is hooked on the pin 90 attached to the basic board 4.
• the extension spring is by its second end attached directly to the basic board 4.
• the put off means 9 is formed by other suitable means, e.g. by a spiral spring, torsion spring etc., or it may be formed by another suitable kind of put off means 9.
• the device for overvoltage protection contains a single varistor VI, whose second contact K2 is coupled with connection point L and the first contact Kl is connected to electrically conductive layer of the basic board 4.
• the breaking-off means 6 In vicinity of connection of the first contact Kl to electrically conductive layer of the basic board 4 in analogical manner to execution in the Fig. 2 to electrically conductive layer of the basic board 4 by a low-fusing joint 5 is attached the breaking-off means 6, which is by means of heat resistant link 8 connected with one outlet of aerial discharge 2, which is with its second outlet coupled with the connection point PE.
• the breaking-off means 6 is further coupled with the put off means 9.
• V2 Upon occurrence of overvoltage at least through one varistor V1, V2 electrical current starts to flow into grounding PE, through which the overvoltage is eliminated without negative influence to the protected electrical circuit.
• the varistor YJ. or V2 When electrical current passes through varistor Vl or V2, the varistor YJ. or V2 is heated a the heat produced is thanks to thermal conductivity guided off to electric conductive layer of the basic board 4 at contacts of the corresponding varistor VI or V2.
• Development of heat in varistors Vl or V2 is also increasing due to ageing of varistors Vl or V2.
• V1 first varistor

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• Engineering & Computer Science (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Fuses (AREA)
• Emergency Protection Circuit Devices (AREA)

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Cited By (13)

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Citations (3)

• 2006
  • 2006-03-14 CZ CZ20060166A patent/CZ2006166A3/cs unknown
• 2007
  • 2007-03-12 WO PCT/IB2007/000585 patent/WO2007105066A1/en active Application Filing

Patent Citations (3)

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