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WO1993021677A1 - Systeme de protection contre les surcharges - Google Patents

Systeme de protection contre les surcharges Download PDF

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Publication number
WO1993021677A1
WO1993021677A1 PCT/SE1993/000324 SE9300324W WO9321677A1 WO 1993021677 A1 WO1993021677 A1 WO 1993021677A1 SE 9300324 W SE9300324 W SE 9300324W WO 9321677 A1 WO9321677 A1 WO 9321677A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrodes
pressure
elastomeric
electrically conductive
abutment
Prior art date
Application number
PCT/SE1993/000324
Other languages
English (en)
Inventor
Per Olov KARLSTRÖM
Original Assignee
Karlstroem Per Olov
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Karlstroem Per Olov filed Critical Karlstroem Per Olov
Priority to DE69314671T priority Critical patent/DE69314671D1/de
Priority to EP93909127A priority patent/EP0725993B1/fr
Priority to JP5518245A priority patent/JPH07505757A/ja
Priority to FI944831A priority patent/FI944831L/fi
Publication of WO1993021677A1 publication Critical patent/WO1993021677A1/fr
Priority to NO943817A priority patent/NO943817L/no

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H77/00—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting
    • H01H77/02—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting in which the excess current itself provides the energy for opening the contacts, and having a separate reset mechanism
    • H01H77/10—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting in which the excess current itself provides the energy for opening the contacts, and having a separate reset mechanism with electrodynamic opening
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01C—RESISTORS
    • H01C10/00—Adjustable resistors
    • H01C10/10—Adjustable resistors adjustable by mechanical pressure or force
    • H01C10/106—Adjustable resistors adjustable by mechanical pressure or force on resistive material dispersed in an elastic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/02—Contacts characterised by the material thereof
    • H01H1/021—Composite material
    • H01H1/029—Composite material comprising conducting material dispersed in an elastic support or binding material

Definitions

  • the present invention relates to a protective device for protecting against overcurrents in electric circuits, said device comprising at least one electrically conduc ⁇ tive body and two electrodes which function to supply circuit current through said conductive body and which lie against the body at corresponding positions either directly or through the medium of an intermediate part, and further comprising pressure means for generating an abutment pressure.
  • the device is primarily intended for use in low voltage systems having an operating voltage of at most 1000 V.
  • short circuiting protectors are mainly comprised of fuses and circuit-breakers which most often possess current limiting properties.
  • the technigue is known to the art and several standards, such as IEC 269 concerning fuses, and ⁇ IEC 947-2 concerning circuit-breakers, have been insti ⁇ tuted.
  • the short-circuiting protector is excited by the short circuiting currents flowing therethrough.
  • the shortcircuiting protector is excited in accordance with two main principles and is therefore divided here into the following groups l and 2:
  • Arc-based, current limiting cut-outs for instance circuit-breakers are excited directly, through the conversion of magnetic energy to mechanical energy, by electrodynamic current forces occurring on the electrical contact system included in the circuit- breaker, or indirectly through the medium of a separate excitation device comprised of an electro ⁇ magnetic release device, a so-called "plunger or schlagstif an onion", which is also excited by the main current.
  • An armature included in a magnetic circuit acts on the electrical contact system and/or on a spring mechanism release device which performs an on/off-function.
  • Remote control is also used, for instance in contactors, for maintaining two stable mechanical states of equilibrium, on and off respectively.
  • Electrical contact systems in which electrodynamic current forces act directly on the electrical contacts are earlier known to the art, for instance from Patent Specifications GB 1,519,559, GB 1,489,010, GB 1,405,377.
  • Hybrids in which the two principles are used are dis ⁇ closed in Patent Specification GB 1,472,412 and in the article "A New PTC Resistor for Power Applications" by R.S. Perkins, et al, published in the journal IEEE Transactions on Components, Hybrids and Manufacturing Technology, Vol. CHMT-5, No. 2, June 1982, pages 225-230 and publications U.S. 3,249,810 and DE 35 446 47, among others .
  • the mass iner ⁇ tia As a result of the mass iner ⁇ tia, the arc is delayed on the electrical contacts in arc-based circuit-breakers, and consequently the arc voltage, important in achieving current limitation, will not reach the values at which the otherwise monotonously growing short circuit current is limited until a rela ⁇ tively long delay time (ms) has lapsed. Furthermore, a very high contact pressure, proportional to the square of the rated or nominal current of the apparatus, is required in order for the electrical contacts to be able to carry rated current under normal operating currents. This also prevents the electrical contacts from separat ⁇ ing quickly, since the contact pressure is opposed to the electrodynamical repelling and separating forces.
  • short-circuiting protectors based on the principles disclosed in categories 1 and 2 above are less suited as short-circuiting protectors or current transient protectors for thyristors or electronic equip ⁇ ment, since they are sensitive to both high current derivatives and high short-circuiting currents can also occur in capacitive circuits or inductive motor circuits with high presumptive short-circuiting currents.
  • Typical values of presumptive short-circuiting currents are
  • Ik 50-100 kA and corresponding current time deriva ⁇ tives from 22-44 kA/ms. With a rated current of 100 A, a conventional fuse will then allow a current peak of
  • a self-restoring short-circuiting protector is mainly comprised of so-called thermistors.
  • the expression PTC- element is an accepted designation of thermistors whose resistivity has a Positive Temperature Coefficient.
  • PTC-elements One problem with PTC-elements is that when heated by the current flowing therethrough and the temperature is reached at which the PTC-elements become self-adjusting, the voltage is taken over by a fragment of the PTC- element and the fragment is subjected to very high stresses, which are liable to destroy the PTC-ele ent.
  • PTC-embodiments in which this problem is eliminated are known, for instance, from European Patent EP 0,038,716.
  • PTC-elements for overload protectors are often construc ⁇ ted of a polymeric material, for instance high-pressure polyethylene, containing particles of an electrically conductive material, for instance lamp black or carbon black, and exhibit a resistivity with high positive temperature coefficient.
  • Ceramic thermistors which exhibit PTC-characteristics are known from Patent Publication GB-A-1,570,138. The most common ceramic thermistors are based on BaTiO or
  • the polymer-based thermistor in comparison with the ceramic thermistor is that its resistance increases monotonously with temperature. It is also relatively cheap to produce.
  • commer ⁇ cially available polymer-type thermistors are designed for relatively low rated or nominal voltages and cannot therefore be used readily in distribution networks for instance.
  • the configuration and electrode connections of the thermistors are normally such that the thermistors are subjected to large repulsion forces at high short-circuiting currents, as a result of anti- parallel current paths, therewith tearing the electrodes apart.
  • polymer-based thermistors have not hitherto been used to any appreciable extent in practice within electric power technology, but have mainly only been used to protect electronic equipment, although the thermal inertia limits the fields of possible appli ⁇ cation.
  • thermoistors will self-restore after a short-cir ⁇ cuit, i.e. thermistors can be reused after a short- circuit, which also applies to circuit-breakers.
  • Elastomers are comprised of all polymers that exhibit elastic properties which are similar to those exhibited by natural rubber. Elastomers can be compressed or stretched within a relatively large permitted elastic area, and return to their original state when the load is removed.
  • Electrically conductive elastomers are a class of rubber and plastics which have been made elec ⁇ trically conductive, either by the addition of metal mixtures or by orientating metal fibres under the influ ⁇ ence of electric fields, or by the addition of different carbon mixtures, or ceramics, for instance V203-material dispersed in the manner described in the article "V203
  • Electrically conductive elastomer are used as pressure transducers within transducer technology. The electrical properties are changed when electrically conductive elastomers are deformed, for instance as a result of being subjected to pressure or tension, which manifests in a change in resistance.
  • Electrically conductive elastomers can be given very low resistances, for instance resistances of 2 mOhmcm or lower, by admixing metal powder.
  • One advantage afforded by elastomers is that they are very soft in comparison with carbon-filled polyethylene and polypropylene, even when containing large quantities of electrically conduc ⁇ tive filler.
  • Such elastomers will have a typical Shore number of between 20-80, according American Standard ASTM D2240 (Q/C).
  • the object of the present invention is to provide a relatively simple and inexpensive overload protector which is able to limit the highest short-circuiting currents that occur in a low voltage network, even at very high current derivatives, and the release charac ⁇ teristic of which, i.e. its response sensitivity, can be adapted readily to the object to be protected.
  • This object is achieved in accordance with the invention with a protective device having the characteristic features set forth in the following Claim 1.
  • the device can replace both conventional fuses and so-called automatic circuit-breakers (MCB) , and possesses the advantages afforded by both of these types of circuit-breaker without suffering their disadvantages, such as the limited length of life of the fuse and the limited circuit breaking ability of the automatic circuit-break ⁇ er on short-circuiting occurrences.
  • MBC automatic circuit-breakers
  • the device which functions as a current limiting element includes at least one electrically conductive elastomer- ic body and two electrodes.
  • the polymer composition of the elastomeric body may be of any known kind and forms no part of the present invention. Examples of suitable elastomers in this respect are particularly butyl, natural, polychlorpropene , neoprene, EPDM and silicone rubber.
  • the electroconductive powder material is prefer ⁇ ably comprised of silver, nickel, cobalt, silver-plated copper, silver-plated nickel, silver-plated aluminium, lampblack, conductive soot or carbon black.
  • the powder material will suitably have a particle size of 0.01-10 micro-meters and the powder filler is suitably present in an amount corresponding to 40-90% of the combined weight of the powder filler and elastomeric material.
  • the resistivity of the electric elastomeric body will preferably lie within the range of 0.1 mohmcm-10 Ohmcm.
  • the bodies may be made of mutually the same or mutually different elastomers and then with mutually the same or mutually different fill ⁇ ers and resistivity.
  • the electrodes are of a convention- al kind, for instance silver-plated copper.
  • the elec ⁇ trodes are preferably orientated so that repulsion forces will occur between the electrodes when high currents pass therethrough.
  • the pressure achieved on the electrodes for instance with a known pressure device described in U.S. 3,914,727, or by a conventional spring mechanism for the on/off function of an electric switch, deforms the convex abutment surface of the elastomeric body, when the device includes such an abutment surface. This deformation will preferably reach at least 5%. A deformation of 5-30% is particularly preferred, as defined with a starting point from the distance between the bodies that borders on a considered elastomeric body, i.e.
  • elastomeric bodies are those which have a hardness between 30-50 IRHD in accord with British Standard BS903/A26, although materials having both a lower and a higher hardness may conceivably be used.
  • the pressure device is provided with pressure exerting means which have spring properties.
  • a spring device of this preferred construction greatly facilitates separation and therewith reduction of the transition area between the convex abutment surface of the elastomer bodies, when such an abutment surface is included, and bordering body.
  • one elastomeric body is stacked on another elastomeric body in accordance with the invention, in the same pressure device.
  • the elastomeric body is cavitary and can be deformed by much more than 30%, the extent of deformation depending on the diameter of the cavity.
  • One conceivable reason for the result achieved by the present invention may be as follows: With the normal passage of current, a low transition resistance is maintained between those elements which are in contact with one another through the transition surface which is formed when the body having a convex abutment surface or the bodies, when more than one such body is included, are deformed by an external pressure device. When high short-circuiting currents occur, the electrodes will separate as a result of current forces. Furthermore, so- called striction forces occur in the transition between the convex abutment surface of the elastomer bodies, when one such abutment surface is included, and border ⁇ ing bodies, due to the configuration of the preferred abutment surface.
  • the current density is greatest along the symmetry line of the cross-sectional surface between the electrodes, meaning that the material is under the greatest stress in this region, therewith preventing the formation of cracks and bubbles in the cross-section at right angles to the current direction.
  • the following advantages are ob ⁇ tained in a current limiting device when the physical properties described in the Background Art are combined, for instance such properties as pressure response of electrically conductive elastomers, transition surfaces, the electrodynamic repulsion effect that is achieved by suitable geometric configuration of electrically conduc ⁇ tive elastomeric bodies and electrodes, together with a suitable choice of electrode material:
  • the device can be made very low-ohmic, because of deformation of the contact transition between elec ⁇ trically conductive elastomeric body and electrode.
  • the element returns to its initial resistance after passing from a low-resistive state to a high-resis ⁇ tive state.
  • Figures la-c are central sectional views of three pre ⁇ ferred embodiments of one part of the invention, this part mainly comprising electrically conductive elastomeric bod ⁇ ies and electrodes;
  • Figure 2 illustrates the resistance R as a func ⁇ tion of the distance d between two elec ⁇ trodes between which an electrically con ⁇ ductive elastomeric body of semi-cylin ⁇ drical cross-section of radius r is com ⁇ pressed;
  • Figure 3 illustrates one embodiment of an inven ⁇ tive current limiting element connected in an electric circuit
  • Figure 4 illustrates the course of the current in the event of a short-circuit with an ele- ment according to Figure 3;
  • Figure 5 shows a comparison between / i dt curves for an inventive current limiting element and a conventional protector, such as a fuse and circuit-breaker, MCCB;
  • Figures 6-7 are central sectional views of an inven ⁇ tive elastomeric body and associated el ⁇ ectrodes, and also a repulsion means;
  • Figures 8-19 illustrate further variants of inventive current limiting elements.
  • FIG. 6 illustrates a current limiting element in accordance with an arrangement analogous with the ar ⁇ rangement illustrated in Figure lb.
  • the current limiting element includes a centrally mounted body (10) in the form of a homogenous cylinder having a diameter of 3 mm and length of 10 mm and being made of a deformable electrically conductive elastomer material, for instance comprising 80 percent by weight silver powder and 20 percent by weight silicone plastic, and two mutually parallel electrodes (11, 12) which are tangential to the body (10) on opposite sides thereof.
  • the elastomeric body (10) has a Shore number of 40 according to BS 903/A26.
  • the elec ⁇ trodes (11, 12) are comprised of angled, silver-coated copper plates having a thickness of 0.7 mm.
  • the elec- trodes are held in abutment with the body (10) with the aid of a spring device (14) which exerts pressure on the electrodes (11, 12) in a known manner and therewith deform the abutment surfaces (10', 10") of the body against respective electrodes, this deformation being about 30%.
  • the sensitivity or response of the arrange ⁇ ment can be enhanced by including a repulsion device (13) of the kind described, for instance, in GB 1,519,559 or GB 1,489,010, or the electrodes may be constructed so that they themselves will give rise to repelling electrodynamic current forces.
  • the repulsion device (13) may be a self- activating magnetic circuit of the kind earlier des ⁇ cribed in U.S. 4,513,270, which is intended to act solely on one electrode and which is directed so that the electrodes will separate from one another under the action magnetic forces or electrodynamic current forces.
  • the resistance across the device is 2 mOh .
  • the device is subjected to high short-circuiting currents, preferably currents above 50 A, and more particularly above 500 A, the current density will increase in the deformed abutment surfaces (10', 10"), wherewith the resistance in the element will increase to 100 mOhm or more. This is sufficient to limit short-circuiting currents in low voltage systems, which through the agency of the preferred arrangement in Figure 6 and the circuit illustrated in Figure 3 limits the short- circuiting currents and produces the current-time dia ⁇ gram shown in Figure 4.
  • Figure 7 illustrates a current limiting element which is similar to the element illustrated in Figure 6 and Figure lc with the exception that the elastomeric body (20) is not an homogenous body.
  • the body of the Figure 7 embodiment includes a cavity (9) which enables deformation of the elastomeric body to be increased to 30% or more, depending on the dimensions of the cavity. This enables a material of relatively high Shore number to be used, for instance a Shore number of 80.
  • the body (20) is preferably deformable so that the resultant convex abutment surface (9') will be in physical contact with the abutment surface (9").
  • Figure 8 illustrates an embodiment of the invention in which two electrically conductive elastomeric bodies (10a, 10b) have been stacked one upon the other, whereas the electrically conductive elastomeric bodies (10a, 10b) of the Figure 9 embodiment have been placed side- by-side.
  • Figures lOa-b illustrate an inventive device in which an electrically conductive elastomeric body (10) according to Figure 7 is placed between two electrodes (11, 12) which extend longitudinally parallel with the body (10).
  • the pressure applied to the electrodes and the elasto ⁇ meric body abutment surfaces (10', 10") is obtained through the agency of the earlier described resilient pressure device.
  • Figure 11 illustrates an inventive device in which an electrically conductive elastomeric body (10) is placed between two electrodes (11, 12) according to Figures lOa-b.
  • a ferromagnetic repulsion circuit (13) surrounds the longitudinally extending electrodes (11, 12) and the elastomeric body (10), and amplifies the repulsion effect of electrode (11) when overcurrents flow through the current limiting element.
  • Pressure is applied to the electrodes and the elastomeric body abutment surfaces (10', 10") by the aforedescribed resilient pressure device.
  • Figure 12 illustrates a device which is analogous with the device shown in Figures lOa-b with the exception that the electrically conductive elastomeric body (10)- is semi-cylindrical in shape and may be firmly anchored to the electrode (12) by means of an electrically con ⁇ ductive adhesive, or may lie free.
  • Figure 13 illustrates an inventive device in which two electrically conductive elastomeric bodies (10a, 10b) are placed between two electrodes (11, 12), between which a further two elastomeric bodies (10c) and (lOd) respectively have been placed, these further bodies surrounding the electrodes (11, 12) .
  • Pressure is applied to the electrodes, and particularly to the elastomeric bodies provided with convex end-surfaces, by the afore ⁇ said, known pressure device.
  • Figure 14 illustrates a further embodiment of the inven ⁇ tion according to the Figure 12 and Figure 9 embodi ⁇ ments, in which the elastomeric bodies (10c, 16a) and (lOe, 16b) respective surrounding electrodes (11, 12) are comprised respectively of electrically conductive elastomer material (10c, lOe) and electrically insulat ⁇ ing elastomeric material (16a, 16b).
  • the respective elastomeric bodies (10c, 16a) and (lOe, 16b) are advan ⁇ tageously moulded in a two-part mould, so that the elastomeric bodies will be mutually joined, and the electrodes are electrically insulated.
  • the electrical connections to the electrodes are not shown in the Figure.
  • Figure 15 illustrates an inventive device according to Figures 6 and 7, in which two electrically insulating, polyethylene bodies (15a, 15b) are disposed parallel with an electrically conductive elastomeric body (10) .
  • the body (10) When the device is subjected to pressure, as symbolized by the force F acting on the electrodes (11, 12) , the body (10) is deformed and will therewith lie against the defining surfaces (15a ⁇ ) and (15b') of the electrically- insulating bodies.
  • an electric insulation which prevents flashover in the event of a short-circuit, at the same time as the elec- trically conductive elastomeric body will not flow outwards, which is otherwise a common problem.
  • Figure 16 illustrates an inventive device in which the electrically conductive elastomeric body (10) includes several convex deformable abutment surfaces (10a', 10b', IOC, 10d'), comprising several integrated elastomeric bodies according to earlier Figures.
  • the elastomeric body (10) is coherent and homogeneous.
  • Figure 17 illustrates an inventive device in which the electrically conductive elastomeric body (10) has a convex deformable abutment surface in a "spline configu ⁇ ration", comprising several integrated elastomeric bodies according to earlier Figures.
  • the elastomeric body (10) is thus coherent and several convex surfaces can be activated, for instance by in ⁇ creasing the pressure with the aid of the pressure device (14).
  • Figures 18a-b illustrate an inventive device which is comprised of two electrically conductive elastomeric bodies (20a, 20b) having convex deformable abutment surfaces (20a', 20b"), and two electrodes (11, 12).
  • the electrodes are surrounded by concentrical, electrically conductive elastomeric bodies (20a, 20b) whose abutment surfaces (20a', 20b') are in physical abutment with one another.
  • the abutment surfaces (20a', 20b') are deformed by pressure exerted by a pressure device (14).
  • the electrodes (11, 12) are provided with electrical con ⁇ necting means (31) and (32) respectively.
  • Figure 19 illustrates an inventive device in which the electrically conductive elastomeric bodies (lOal, 10a2, 10a3, 10a4) have convex-defining surfaces which are orientated perpendicularly to the convex-defining sur- faces of the electrically conductive bodies (lObl, 10b2, 10b3, 10b4).
  • the device includes two electrodes (11, 12) for conducting current therethrough, electrodes on which a pressure device exerts pressure such as to deform the abutment surfaces (lOal...lObl...) .

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Adjustable Resistors (AREA)
  • Fuses (AREA)
  • Emergency Protection Circuit Devices (AREA)
  • Thermistors And Varistors (AREA)
  • Amplifiers (AREA)
  • Centrifugal Separators (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Crushing And Grinding (AREA)
  • Control Of Multiple Motors (AREA)
  • Control Of Eletrric Generators (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

Un protecteur contre les surcharges comprend au moins un corps (10) fabriqué en matériau élastomère électroconducteur, et deux électrodes. La surface de contour (10') du corps élastomère est conçue pour reposer et être déformée contre une surface d'au moins un autre corps (11, 12). Un dispositif de pression (14) est prévu pour exercer une pression sur le corps (10). Le dispositif de pression est de préférence élastique. De cette façon, le protecteur contre les surcharges passera très rapidement d'un état faiblement résistif résistance à un état fortement résistif si des surcharges de courant se produisent, après quoi le protecteur contre les surcharges reviendra à sa résistance initiale et pourra être réutilisé.
PCT/SE1993/000324 1992-04-16 1993-04-14 Systeme de protection contre les surcharges WO1993021677A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
DE69314671T DE69314671D1 (de) 1992-04-16 1993-04-14 Überlastschutz
EP93909127A EP0725993B1 (fr) 1992-04-16 1993-04-14 Systeme de protection contre les surcharges
JP5518245A JPH07505757A (ja) 1992-04-16 1993-04-14 過負荷保護システム
FI944831A FI944831L (fi) 1992-04-16 1993-04-14 Ylikuorman suojajärjestelmä
NO943817A NO943817L (no) 1992-04-16 1994-10-10 Vern for beskyttelse mot overströmmer i elektriske kretser

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9201223A SE470118C (sv) 1992-04-16 1992-04-16 Anordning för skydd mot överström i elektriska kretsar
SE9201223-6 1992-04-16

Publications (1)

Publication Number Publication Date
WO1993021677A1 true WO1993021677A1 (fr) 1993-10-28

Family

ID=20385990

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1993/000324 WO1993021677A1 (fr) 1992-04-16 1993-04-14 Systeme de protection contre les surcharges

Country Status (10)

Country Link
EP (1) EP0725993B1 (fr)
JP (1) JPH07505757A (fr)
AT (1) ATE159385T1 (fr)
CZ (1) CZ238694A3 (fr)
DE (1) DE69314671D1 (fr)
FI (1) FI944831L (fr)
HU (1) HUT73373A (fr)
NO (1) NO943817L (fr)
SE (1) SE470118C (fr)
WO (1) WO1993021677A1 (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995034931A1 (fr) * 1994-04-22 1995-12-21 Seldim I Västerås Aktiebolag Dispositif de protection contre les courants de surcharge dans les circuits electriques
WO1998049694A3 (fr) * 1997-04-14 1999-01-28 Asea Brown Boveri Resistance electrique variable
US5929744A (en) * 1997-02-18 1999-07-27 General Electric Company Current limiting device with at least one flexible electrode
US5977861A (en) * 1997-03-05 1999-11-02 General Electric Company Current limiting device with grooved electrode structure
US6124780A (en) * 1998-05-20 2000-09-26 General Electric Company Current limiting device and materials for a current limiting device
US6133820A (en) * 1998-08-12 2000-10-17 General Electric Company Current limiting device having a web structure
US6191681B1 (en) 1997-07-21 2001-02-20 General Electric Company Current limiting device with electrically conductive composite and method of manufacturing the electrically conductive composite
US6290879B1 (en) 1998-05-20 2001-09-18 General Electric Company Current limiting device and materials for a current limiting device
US6323751B1 (en) 1999-11-19 2001-11-27 General Electric Company Current limiter device with an electrically conductive composite material and method of manufacturing
US6373372B1 (en) 1997-11-24 2002-04-16 General Electric Company Current limiting device with conductive composite material and method of manufacturing the conductive composite material and the current limiting device
US6535103B1 (en) 1997-03-04 2003-03-18 General Electric Company Current limiting arrangement and method
FR2996638A1 (fr) * 2012-10-08 2014-04-11 Univ Haute Alsace Capteur de pression flexible

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018008367A1 (fr) * 2016-07-06 2018-01-11 アルプス電気株式会社 Appareil de détection

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2752558A (en) * 1953-04-22 1956-06-26 Ernest M Kane Electric transducer
US3509296A (en) * 1967-10-23 1970-04-28 Ncr Co Resilient variable-conductivity circuit controlling means
US4163204A (en) * 1977-12-30 1979-07-31 Shin-Etsu Polymer Co., Ltd. Pressure-sensitive resistors
EP0267544A2 (fr) * 1986-11-12 1988-05-18 Richter, Dietrich H. Capteur de pression
WO1990013800A1 (fr) * 1989-05-03 1990-11-15 Ab Elektronik Gmbh Palpeur electronique de pression

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2752558A (en) * 1953-04-22 1956-06-26 Ernest M Kane Electric transducer
US3509296A (en) * 1967-10-23 1970-04-28 Ncr Co Resilient variable-conductivity circuit controlling means
US4163204A (en) * 1977-12-30 1979-07-31 Shin-Etsu Polymer Co., Ltd. Pressure-sensitive resistors
EP0267544A2 (fr) * 1986-11-12 1988-05-18 Richter, Dietrich H. Capteur de pression
WO1990013800A1 (fr) * 1989-05-03 1990-11-15 Ab Elektronik Gmbh Palpeur electronique de pression

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995034931A1 (fr) * 1994-04-22 1995-12-21 Seldim I Västerås Aktiebolag Dispositif de protection contre les courants de surcharge dans les circuits electriques
US5929744A (en) * 1997-02-18 1999-07-27 General Electric Company Current limiting device with at least one flexible electrode
US6535103B1 (en) 1997-03-04 2003-03-18 General Electric Company Current limiting arrangement and method
US5977861A (en) * 1997-03-05 1999-11-02 General Electric Company Current limiting device with grooved electrode structure
US6292338B1 (en) 1997-04-14 2001-09-18 Abb Ab Electric coupling device, electric circuit and method in connection therewith
WO1998049694A3 (fr) * 1997-04-14 1999-01-28 Asea Brown Boveri Resistance electrique variable
US6191681B1 (en) 1997-07-21 2001-02-20 General Electric Company Current limiting device with electrically conductive composite and method of manufacturing the electrically conductive composite
US6373372B1 (en) 1997-11-24 2002-04-16 General Electric Company Current limiting device with conductive composite material and method of manufacturing the conductive composite material and the current limiting device
US6540944B2 (en) 1997-11-24 2003-04-01 General Electric Company Current limiting device with conductive composite material and method of manufacturing the conductive composite material and the current limiting device
US6290879B1 (en) 1998-05-20 2001-09-18 General Electric Company Current limiting device and materials for a current limiting device
US6124780A (en) * 1998-05-20 2000-09-26 General Electric Company Current limiting device and materials for a current limiting device
US6366193B2 (en) 1998-05-20 2002-04-02 General Electric Company Current limiting device and materials for a current limiting device
US6133820A (en) * 1998-08-12 2000-10-17 General Electric Company Current limiting device having a web structure
US6323751B1 (en) 1999-11-19 2001-11-27 General Electric Company Current limiter device with an electrically conductive composite material and method of manufacturing
US6711807B2 (en) 1999-11-19 2004-03-30 General Electric Company Method of manufacturing composite array structure
FR2996638A1 (fr) * 2012-10-08 2014-04-11 Univ Haute Alsace Capteur de pression flexible
WO2014056932A1 (fr) * 2012-10-08 2014-04-17 Université De Haute Alsace Capteur de pression flexible

Also Published As

Publication number Publication date
HU9402967D0 (en) 1995-02-28
SE9201223D0 (sv) 1992-04-16
NO943817D0 (no) 1994-10-10
DE69314671D1 (de) 1997-11-20
EP0725993B1 (fr) 1997-10-15
NO943817L (no) 1994-10-10
SE9201223L (sv) 1993-10-17
JPH07505757A (ja) 1995-06-22
CZ238694A3 (en) 1995-01-18
FI944831A0 (fi) 1994-10-14
SE470118B (sv) 1993-11-08
SE470118C (sv) 1998-02-23
ATE159385T1 (de) 1997-11-15
HUT73373A (en) 1996-07-29
FI944831A7 (fi) 1994-12-14
FI944831L (fi) 1994-12-14
EP0725993A1 (fr) 1996-08-14

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