NO161028B

NO161028B - HANGING DEVICE FOR INSTALLATION IN GALVANIC CONTACT WITH THE LEADER TO A THIN PLASTIC LAYER ISOLATED AIR CONDITION.

Info

Publication number: NO161028B
Application number: NO842383A
Authority: NO
Inventors: Keijo Erkki Matikainen; Arto Ilpo Antero Hinkkuri; Keijo Juhani Niemelae
Original assignee: Nokia Oy Ab
Priority date: 1983-06-15
Filing date: 1984-06-14
Publication date: 1989-03-13
Also published as: SE8403185D0; FI69537B; SE460446B; SE8403185L; FI832181L; NO842383L; NO161028C; FI832181A0; FI69537C

Description

Overstrømsrele for trefasestrømkretser med termisk utløsning. Overcurrent relay for three-phase circuits with thermal release.

Foreliggende oppfinnelse angår et overstromsrelé av den art som angis i innledningen til hovedkravet. The present invention relates to an overcurrent relay of the type stated in the introduction to the main claim.

OverstrSmsreléer av denne art har den fordel at de ved feil i en av trefaseledningene eller ved usymmetrisk belastning Overvoltage relays of this type have the advantage that in the event of a fault in one of the three-phase lines or in the event of an asymmetrical load

reagerer umiddelbart og ikke forst etter oppnåelse av reacts immediately and not until after the achievement of

den overbelastningsverdi for hvilken reléet ved symmetrisk belastning er innstilt. Ved tidligere kjente utforelser av sådan-ne reléer har manovreringsorganene bestått av sleider, som har utfSrt en lineær forskyvningsbevegelse. Ved en sådan konstruk-sjon fins en betydelig fare for driftsforstyrrelser p.g.a. the overload value for which the relay is set for symmetrical loading. In previously known embodiments of such relays, the maneuvering means have consisted of slides, which have performed a linear displacement movement. With such a construction, there is a significant risk of operational disruptions due to

opptredende friksjon og derav folgende slitasje ved lagrings- occurring friction and consequent wear during storage

-stedene. - the places.

Denne ulempe er ved overstromsreléet ifolge oppfinnelsen eliminert ved at manovreringsorganene utgjores av svingarmer, som er utfort og lagret slik som angitt i den karakteriserende del av hovedkravet. This disadvantage is eliminated in the overcurrent relay according to the invention by the fact that the maneuvering means are made of swing arms, which are extended and stored as stated in the characterizing part of the main claim.

Oppfinnelsen forklares nærmere i samband med tegningen, som viser et utforelseseksempel. Fig. 1 er et skjema av et relé ifolge oppfinnelsen, idet fig. 2 viser den nedre del av reléet ifolge fig. 1, sett forfra. The invention is explained in more detail in connection with the drawing, which shows an exemplary embodiment. Fig. 1 is a diagram of a relay according to the invention, as Fig. 2 shows the lower part of the relay according to fig. 1, front view.

Det på tegningen viste termiske overstrdmsrelé er anordnet The thermal overload relay shown in the drawing is arranged

på en isoleringsramme 10. Tre bimetallstrimler 16,17,18, bestemt til å inngå i et trefasesystem, er festet på rammen 10 og er forsynt med hver sin oppyarmningsvinding 20,21,22, hvis nedre ende er sluttet txL den respektive strimmels 16,17,18 nedre ende og hvis ovre ende er sluttet til hver sin klemme 24,25,26 på rammen. De tre faseledninger har således hver sitt bimetallorgan, bestående av bimetallstrimmel og oppvarmnings-vinding. on an insulating frame 10. Three bimetallic strips 16,17,18, intended to form part of a three-phase system, are fixed on the frame 10 and are each provided with an arming winding 20,21,22, the lower end of which is terminated txL the respective strip 16, 17,18 lower end and whose upper end is connected to a separate clamp 24,25,26 on the frame. The three phase lines thus each have their own bimetallic element, consisting of a bimetallic strip and a heating winding.

Bimetallstrimlene 16-18 påvirker hver for seg ved hjelp av The bimetallic strips 16-18 influence each one by means of

hver sin justeringsskrue 28,29,30 en av isoleringsmateriale bestående dobbeltarm 32 med en oppadrettet arm 32<*> i forma av en plate som strekker seg forbi de tre justeriiigsskruer 28,29,30, og en nedadrettet vinkelboyd arm 32". Dobbeltarmen 32 er ved hjelp av en tapp 33 oppiågret i den nedre del av en annen dobbeltarm 34. Denne dobbeltarm 34 er svingbar omkring en aksel 36 på en glidesko 38, som er flyttbar i horisontal-planet ved hjelp av en justeringsskrue 40, idet en trykkf jaer 42 holder glideskoen 38 til anlegg mot justeringsskruen 40. Dobbeltarmens 34 tivre arm 34' samvirker «ed en innstillings-skrues 44 nedre ende 44', utformet som eksentertapp eller som en slags kamskive. Dobbeltarmens nedre arm 34" er ved sin ytterende utformet som en plate 46, som strekker seg forbi de tre bimetallstrimlenes 16-18 nedre ender og er forsynt med tre hull 48,49,50, gjennom hvilke justeringsskruene strekker seg med passende klaring. Dobbeltarmens 32 nedre vinkel-boyde del 32" berbrer enmnovreringspinne 52 på en mikrobryter 54, som er innstilt på en slik måte at den forst manovreres etter overskridelsen av en viss, på pinnen 52 innvirkende kraft, og at den etter opphor av denne kraft går tilbake til utgangsstillingen. each adjusting screw 28,29,30 a double arm 32 consisting of an insulating material with an upwardly directed arm 32<*> in the form of a plate that extends past the three adjusting screws 28,29,30, and a downwardly directed angle-shaped arm 32". The double arm 32 is, by means of a pin 33, mounted in the lower part of another double arm 34. This double arm 34 is pivotable around an axle 36 on a sliding shoe 38, which is movable in the horizontal plane by means of an adjustment screw 40, as a pressure spring 42 holds the sliding shoe 38 in contact with the adjusting screw 40. The upper arm 34' of the double arm 34 cooperates with the lower end 44' of an adjusting screw 44, designed as an eccentric pin or as a kind of cam disc. The lower arm 34" of the double arm is designed at its outer end as a plate 46, which extends past the lower ends of the three bimetallic strips 16-18 and is provided with three holes 48,49,50, through which the adjusting screws extend with suitable clearance. The lower angle-shaped part 32" of the double arm 32 supports an actuation pin 52 on a microswitch 54, which is set in such a way that it is only actuated after exceeding a certain force acting on the pin 52, and that it returns after the cessation of this force to the starting position.

Når bimetallstrimlene 16-18 på grunn av symmetrisk overbelastning i trefasesystemet boyes så pass meget at dobbeltarmen 34 svinges moturs, slik at dens ovre armdel 34• blir liggende mot innstillingsskruens 44 ende 44<1>, svinges dobbeltarmen 32 medurs etter opphor av dobbeltarmens 34 bevegelse, hvor-ved pinnen 52 fores nedad for å mandvrere mikrobryteren 54, som i sin tur bryter eksempelvis en kontaktors magnetiser-inga tr om , slik at også strommen i trefasesystemet brytes. Mikrobryteren 54 kan selvsagt også styre et annet koplingsorgan for å oppheve overbelastningen i trefasesystemet. When the bimetallic strips 16-18 due to symmetrical overload in the three-phase system are bent so much that the double arm 34 is swung counter-clockwise, so that its upper arm part 34• lies against the end 44<1> of the setting screw 44, the double arm 32 is swung clockwise after the movement of the double arm 34 has stopped , where the pin 52 is fed downwards to actuate the microswitch 54, which in turn breaks, for example, the magnetizing current of a contactor, so that the current in the three-phase system is also broken. The microswitch 54 can of course also control another switching device to cancel the overload in the three-phase system.

Nevnte koplingsforlop ved symmetrisk overbelastning i et trefasesystem forutsetter at overbelastningen er jevnt fordelt i alle tre faseledninger i systemet. Det kan imidlertid også forekomme at bare en av faseledningene i trefasesystemet er overbelastet eller at overbelastningen er usymmetrisk fordelt, i hvilket tilfelle mikrobryteren 54 utldses på folgende måte: Den eller de bimetallstrimler, som forer den minste overbelastning, eller som ikke forer noen overbelastning i det hele tatt, forblir i det vesentlige i sin på tegningen viste stilling og holder igjen dobbeltarmen 34 og dens plate 46, mens den eller de bimetallstrimler, som har den storste overbelastning og som er mest oppvarmet, boyes moturs, innebærende at dobbeltarmen 32 svinges medurs og mikrobryteren 54 utloses innen dobbeltarmen 34 overhodet kommer til å svinges nevne-verdig og med sin ovre ende 34' bringes til anlegg mot innstillingsskruen 44. Dette har den fordel at overstromsreléet ved usymmetrisk overbelastning allerede medfbrer ut-lbsning av strbmkretsens koplingsorgan lenge for den maksimale overbelastningsverdi nås, d.v.s. uavhengig av den maksimale overbelastning, for hvilken reléet er innstilt. Bimetallstrimlene 16,17,18 kan innbyrdes og med hensyn til den for mikrobryterens 54 manbvrering nbdvendige strbmverdi justeres ved hjelp av justeringsskruene 28,29,30, mens over-belastningsverdien, som innstilles ved hjelp av innstillingsskruen 44, kan justeres ved hjelp av justeringsskruen 40. The aforementioned connection procedure for symmetrical overload in a three-phase system assumes that the overload is evenly distributed in all three phase lines in the system. However, it can also happen that only one of the phase lines in the three-phase system is overloaded or that the overload is asymmetrically distributed, in which case the microswitch 54 is triggered in the following way: The bimetallic strip(s) that carries the smallest overload, or that does not carry any overload in the on the whole, remains essentially in its position shown in the drawing and retains the double arm 34 and its plate 46, while the bimetallic strip or strips, which have the greatest overload and which are the most heated, are bent counterclockwise, meaning that the double arm 32 is swung clockwise and the microswitch 54 is released before the double arm 34 comes to swing significantly and with its upper end 34' is brought into contact with the setting screw 44. This has the advantage that the overcurrent relay in the event of an asymmetric overload already results in tripping of the circuit's switching device long before the maximum overload value reached, i.e. regardless of the maximum overload for which the relay is set. The bimetallic strips 16,17,18 can be interlocked and with regard to the current value required for the operation of the microswitch 54 adjusted using the adjusting screws 28,29,30, while the overload value, which is set using the adjusting screw 44, can be adjusted using the adjusting screw 40 .

Claims

1. Overcurrent relay for three-phase power circuits with thermal tripping by means of bimetallic means in each three-phase line, which bimetallic means (16,17,18) are arranged to directly or indirectly affect an electrical coupling means (54), the bimetallic means (16,17, 18) is arranged to influence a first actuation device (32), which cooperates with a second actuation device (34) in such a way that the bimetallic devices partly by symmetrical overloading of the three-phase lines by means of the first actuation device (32), which in relation to the second maneuvering member (34) remains in its position, the second maneuvering member (34) displaces just forward until abutment against a stop (44'), after which the first maneuvering member (32) is displaced, which is arranged to affect the electrical coupling member ( 54), partly in the event of asymmetrical overloading of the three-phase lines by means of the bimetallic element or elements that carry the smallest overload, the second actuation element (34) remains in its path lling, and with the help of the bimetallic member(s) which absorb the greatest overload, the first maneuvering member (32) moves to influence the coupling member (54), characterized in that the two maneuvering members (32,34) are made of swing arms, of in which the first swing arm (32) is supported on a first swing shaft (33) arranged on the second swing arm (34), while the second swing arm (34) is supported on a fixed second swing shaft arranged at a distance from the first swing shaft (33) ( 36), as the first swing arm (32) has two arm parts (32', 32"), of which one (32') cooperates with the bimetallic members (16, 17, 18) and the other (32<n>) with the electrical coupling means (54).

2. Overcurrent relay according to claim 1, characterized in that the coupling element (54) is designed as a microswitch.

3. Overcurrent relay according to claim 1, characterized in that the second swing arm (34) is designed with a recess (between 34" and 46), in which the bimetal members (16,17, 18) engage and in which the first swing arm (32) is arranged.

4. Overcurrent relay according to claim 1, characterized in that the second swing arm (34) is stored on a movable member (38), the position of which can be varied by means of an adjustment screw (40).

5" Overcurrent relay according to claim 1, characterized in that the stop is extended as an eccentric pin (44') or cam disc.

6. Overcurrent relay according to claim 1, characterized in that the first and/or second swing arm is provided with an elongated plate (32' or 46), which bridges over the bimetallic members (16,17,18).

7. Overcurrent relay according to claim 1, characterized in that the first swing arm (32) is provided with a surface (below 32"), which essentially extends along a circular arc with the swing axis (36) of the second swing arm (34) as the center and which is arranged to influence the coupling member (54).