AU672203B2

AU672203B2 - Automatic circuit breaker

Info

Publication number: AU672203B2
Application number: AU41579/93A
Authority: AU
Inventors: Adolf Tetik
Original assignee: Felten and Guilleaume Austria AG
Current assignee: Felten and Guilleaume Austria AG
Priority date: 1992-06-29
Filing date: 1993-06-28
Publication date: 1996-09-26
Anticipated expiration: 2013-06-28
Also published as: GR940300029T1; EP0577586A1; AT404648B; ATA131992A; HU217733B; DK0577586T3; TNSN93069A1; AU4157993A; PL170273B1; CN1081785A; GR3024584T3; CZ283475B6; ES2107000T3; HUT67507A; CZ125793A3; SK67493A3; SK282149B6; PL299448A1; MY114513A; ATE156304T1

Abstract

An automatic circuit breaker has a moving switching link (5) on which a supporting lug (4) is arranged which can pivot with respect thereto. The supporting lug (4) supports a latch bearing (6) and a latch (3) (which can be latched to one another) such that they can pivot. The latch (3) is coupled to an operating knob (1) via a clip (bracket) (2). The bearing (7) for the latch (3) on the supporting lug (4) can be used to operate a contact position indicator (8) and a further switching link. The supporting lug (4) improves the tripping behaviour of the automatic circuit breaker, since the latch bearing (6) and the latch (3) are not mounted directly on the switching link (5), so that the switching link (5) is relieved of load. <IMAGE>

Description

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AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT ir

I

Application Number: Lodged: ee Invention Title: AUTOMATIC CIRCUIT BREAKER r r r r The following statement is a full description of this invention, including the best method of performing it known to :-US AUTOMATIC CIRCUIT BREAKER The present invention relates to an automatic circuit breaker having a contact arm adapted to contact a fixed contact, in which the contact arm having an opening (20) is provided through which a pivot axis (11) extends, with a support plate which is pivotable about the swivel axis (11) integral with the housing, with a lock pawl which is pivotably mounted on the support plate (4) and which by means of a bracket is coupled with a control knob and with a pawl body which is pivotably mounted with respect to the support plate (4) whereby the pawl body is forced by a torsion spring (16) to pivot into its operative position coupled with the lock pawl in which a projection of the lock pawl engages a shoulder (10) of the pawl body whereby the contact arm is biased by a spring (15) pulling it into its open position.

Such automatic breakers are already known. By way of example EP-0 S 295 158 describes an automatic circuit breaker, in which the contact arm is 15 swivel-mounted about an axis of rotation integral with the housing. The contact arm bears a pawl body having three arms. Acting on one arm of the pawl body oooeoe in the case of the known automatic circuit breaker is a bimetallic trigger, and on the second arm of the trigger, a rammer of a magnetic trigger.

The third arm of the pawl body cooperates with a pawl swivel-mounted on 20 the contact arm.

Linked to the pawl in the known automatic circuit breaker, a bracket is connected by its other end to a operating handle which is swivel-mounted in the :housing.

The contact arm is biased by a tension spring to an open position.

The operating handle also is biased by a spring which endeavours to bring the operating handle into position corresponding to the open state of the automatic circuit breaker -the off-position.

The disadvantage of this known embodiment is that both the pawl body and the pawl itself are swivel mounted directly on the contact arm, resulting in a construction adversely influencing the release performance of the contact arm.

The object of the present invention is to produce an automatic circuit la breaker of the type initially described which is improved on the known embodiment with respect to its release performance.

According to the present invention the solution is provided whereby the pawl body and the pawl are swivel-mounted on a support plate connected to the contact arm and pivoting relative thereto.

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0*S ne0 a oo *o °o o With the construction according to the present invention the contact arm no longer directly supports the pawl body on the one hand and the pawl on the other.

Preferred and advantageous embodiments of the invention are the subject of the sub-claims.

Further details and advantages of the invention are explained hereinbelow with reference to the accompanying diagrams in which an automatic circuit breaker and two embodiments of the invention are shown as application examples.

Figure 1 shows an automatic circuit breaker with the top shell removed, Figure 2 shows a first embodiment in the on-position, Figure 3 shows the embodiment of Figure 2 in the off-position, Figure 4 shows a modified embodiment in the on-position, and Figure 5 shows the embodiment of Figure 4 in the off-position.

All components of the automatic cutout illustrated in Figure 1 are accommodated in a housing which comprises a sub-shell 44 and a top shell, not shown in the diagram.

The automatic circuit breaker illustrated in Figures 1 to 5 and integrated in Figure 1 into an automatic cutout has swivel-mounted in the housing an 20 operating handle 1 which is coupled with a pawl 3 of the switch lock of the automatic circuit breaker by means of a bracket.

The automatic circuit breaker is fitted with a bimetallic trigger 27 and a magnetic trigger 17. Bimetallic trigger 27 acts by means of a tension bracket 13 displaceable guided in intermediate shell 44 and magnetic trigger 17 by means of its armature 17' acts on a pawl body 6 of the automatic circuit breaker.

An arc quench chamber 18 with deionisation plates is accommodated in the automatic circuit breaker.

Provided in the automatic cutout are externally accessible terminals for attaching power lines. The power circuit results such that the terminal angle of the right terminal (in Figure 1) is electrically conductively connected with bimetallic trigger 27. Said bimetallic trigger 27 is in turn electrically conductively connected with movable contact arm 5 and with magnetic trigger 17 when the contacts are closed. Magnetic trigger 17 is electrically conductively connected with the terminal angle of the other terminal (the left, in Figure 1) of the automatic circuit breaker. Conductor wire 25 shown in Figure 1 is provided only when the automatic circuit breakers as illustrated in Figure 1 is combined with a fault current circuit breaker.

Operating handle 1 swivel-mounted in the housing is stressed by a spring 1' into the pivoting position shown in Figures 1 and 3 corresponding to the offposition.

Operating handle 1 is coupled with pawl 3 of the switch lock of the automatic cutout by means of bail 2. Pawl 3 is swivel-mounted on a support plate 4 by means of a bolt 7 or a hollow rivet serving as a bearing. Pawl 3 is .designed in a U-shape, whereby openings are provided in both legs of the pawl 3 for taking up bolt 7 or the hollow rivet. Provided on the cross member of pawl 3 is a boss 9 which, as will be described later, can engage behind a shoulder on pawl body 6 to lock pawl 3 in with pawl body 6.

Pawl body 6 is swivel-mounted on support plate 4, whereby both support plate 4 and pawl body 6 are plugged by means of a pivot axis 11 integral with the housing and can be pivoted about the same. Support placer 4 is pivotably connected to a contact arm 5 for example by means of a hollow rivet 12, The 25 axle (hollow rivet 12), around which support plate 4 can pivot opposite contact arm 5, is located between swivel axis 11 solid with the housing for pawl body 6, contact arm 5 and support plate 45 and free end of contact arm bridge 5 which when in the on-position lies on the contact integral the housing of the automatic'.

circuit breaker component.

Support plate 4 is designed as a U-shape and is swivel-mounted in the vicinity of its legs by means of hollow rivet 12 on switch bridge 5. Engaging in openings in the legs of support plate 4 is bolt 7 (or the hollow rivet) such that bolt 7 bearing pivotably on support plate 4 and hollow rivet 12 is each set into two bearing openings in support plate 4 resulting in symmetrical loading.

A torsion spring 16 is plugged by means of boss 14 surrounding the bearing opening for axle 11 in pawl body 6. An end 16' of torsion spring 16 hooked into a hook 4' on support plate 4 and opposite end 16' of torsion spring 16 is hooked into a hook 6' on pawl body 6. Torsion spring 16 stresses pawl body 6 such that its end nearest pawl 3 and exhibiting shoulder 10 is moved onto pawl 3.

Provided in switch bridge 5 is a bearing opening designed as an elongated slot 20, as in Figures 4 and 5, through which engages swivel axis 11 solid with the housing, by means of which both support plate 4 and pawl body 6 15 are plugged with their bearing openings.

*Assigned to end 22 at bottom in Figure 2 opposite to pawl 3 is armature 17' of magnetic trigger 17 and bimetallic trigger 27 is assigned by means of tension bracket 13 which engages on a deviation 21 of pawl body 6. If pawl body 6, under the effect of armature 17' of magnetic trigger 17 or of tension bracket 13 displaced by bimetallic trigger 27 against the effect of torsion spring 16, is swung clockwise as in Figure 2, boss 9 of pawl 3 comes free from shoulder 10 on pawl body 6 and pawl 3, as in Figure 2, swings anti-clockwise, such that the arrangement of pawl 3 and bracket 2 buckles. At the same time a tension spring 16 suspended in a hole 19 in switch bridge 5 distances contact 25 arm 5 from the contact integral with the housing by swinging around axis 11 solid with the housing. In this way the switch finally reaches the off-position demonstrated in Figures 1 and 3.

When contact arm 5 is swung into the off-position shown in Figure 3, pawl 3 is again locked on pawl body 6, since on the one hand pawl body 6 pivots towards pawl 3 by means of torsion spring 16 and on the other pawl 3 is swung by bracket 2 under the effect of control knob 1, which is stressed clockwise by is inbuilt torsion spring for so long that boss 9 of pawl 3 snaps in behind shoulder 10 on pawl body 6. When control knob 1 is again swivelled anticlockwise into the on-position shown in Figure 2, contact arm 5 swings and the switch is switched on again.

In that support plate 4 can be swivelled opposite contact arm 5, support plate 4 and pawl body 6 can be pivoted around a common axis, (formed by pivot axis 11 solid with the housing). At the end of this closing procedure, when the end of contact arm 5 assigned to the contact integral with the housing lies thereon, contact arm 5 can pivot further around the point of contact between its end and the contact solid with the housing, since swivel axis 11 solid with the 15 housing is taken up in elongated slot 20 of contact arm 5 which can accordingly move relative to swivel axis 11. In the on-position swivel axis 11 no longer lies I on the end nearest pawl body 5 of elongated slot 20 in contact arm 5, rather it oo:. is found at a distance from this end. Thereby the opposite assignment of the Si" decisive components for release, namely pawl 3 and pawl body 6, are not altered, as both these components are not supported directly on contact arm rather on support plate 4 which does not move relative to pawl 3 and pawl body 6 during the abovenmentioned movement of contact arm 5 at the end of the closing procedure. There is no longer any alteration to the position of end 22 and of deviation 21 of pawl body 5 which are assigned to the armature of the 25 impact armature trigger or to tension bracket 13 of the bimetallic trigger.

oe In the embodiment illustrated in Figures 1, 4 and 5 a contact position indicator 8 is additionally provided. Said contact position indicator 8 is swivelmounted in the housing around an axis 23 and exhibits a curved section, assigned to an opening in the housing wall and externally visible through said opening. Contact position indicator 8 further exhibits a lever arm 8' in which is provided a curved, slotted recess 28. Bolt 7 which pivotably bears pawl 3 on support place 4, engages in recess 28 in lever arm 8' of contact position indicator 8, such that the latter is taken along with the opening and closing, and indicates the positions of contact arm 5, that is, the on-position and the offposition.

Bolt 7 which connects pawl 3 with support plate 4 can project through a slot in sub-shell 44 out of the housing, in which the automatic cutout is accommodated, and into a neighbouring housing component, in which a fault circuit component of a combined aucomatic circuit breaker is accommodated.

15 The bearing of pawl 3 on support plate 4 can also be a hollow axis, such as a hollow rivet, which forms the pivoting connection between support plate 4 and pawl 3. With the embodiment having contact position indicator 8 the hollow axis engages in curved, slotted recess 28 in lever 26 of contact position indicator 8, such that the latter is taken along with the opening and closing, and indicates the positions of contact arm 5, that is, the on-position and the offposition.

Insofar as it is provided, bolt 7 can be plugged through the hollow axis connecting pawl 3 with support plate 4.

The automatic circuit breaker according to the present invention can also 25 be equipped with intermittent switching in, in which case a spring-loaded accumulator is provided in operating handle 1, such that bracket 2 swings contact arm 5 into its on-position regardless of the pivoting movement of operating handle 1 only when sufficient resilience is stored and a restraint mechanism is overcome. This restraint mechanism can be a simple sprung tongue which is attached in the housing and which engages on the part of operating handle 1 connected to bracket 2. The restraint mechanism releases this part only when the spring-loaded accumulator in operating handle 1 is S sufficiently loaded for intermittent switching in.

In summary, the invention can be represented as follows: An automatic circuit breaker has a movable contact arm on which is disposed a pivotable support plate Support plate pivotably bears a pawl body and pawl which lock together. Pawl is connected to a operating handle by means of a bracket Bearing of pawl on support plate (4) can be enlisted to actuate a contact position indicator and a further contact arm. The release performance of the automatic circuit breaker is improved by means of support plate since pawl body and pawl are not borne directly on contact arm in such a way that contact arm is unloaded.

9 *~e *oo e

Claims

1. Automatic circuit-breaker having a movable contact arm adapted to contact a fixed contact, in which movable contact arm a bearing opening (20) is provided through which a swivel axis (11) extends, with a support plate (4) which is pivotable about the swivel axis (11) being integral with the circuit breaker housing, with a lock pawl which is pivotably mounted on the support plate and which by means of a bracket is coupled with a control knob (1) and v v~l a pawl body which is pivotably mounted with respect to the support plate whereby the pawl body is forced by a torsion spring (16) to pivot into its operative position coupled with the lock pawl in which a projection (9) of the lock pawl engages a shoulder (10) of the pawl body whereby the movable contact arm is biased by a spring (15) pulling it into its open position, characterized in that the movable contact arm is pivotably mounted on the support plate about an axis that the axis (12) about which the movable contact arm is pivotably mounted is spaced from the swivel axis (11) of the support plate and is arranged between the swivel axis (11) integral with the housing and that end of the movable contact arm adapted to S.:i contact the fixed contact, that the bearing opening (20) in the movable contact arm through which also extends the swivel axis (11) which carries the support plate is a slot, and that the pawl body is pivotable about said swivel axis (11) as the support plate

2. Automatic circuit breaker as claimed in Claim 1, characterised in that the lock pawl is designed in a U-shape and that the lock pawl is pivotally mounted on the support plate by means of openings provided in its legs. 9

3 Automatic circuit breaker as claimed in Claim 2, characterised in that the lock pawl includes on the base of the U the projection facing the pawl body, which with the pawl locked in with the pawl body lies on the shoulder (10) of the pawl body.

4. Automatic circuit breaker as claimed Claim 2 or 3, characterised in that for pivotable bearing of the lock pawl on the support plate a hollow axis, optionally a hollow rivet, is provided which engages in a crescent-shaped opening of a swivel-mounted contact position indicator.

Automatic circuit breaker as claimed in Claim 4, characterised in that a bolt set in the hollow axis is guided through a housing wall of the automatic circuit breaker and coupled with a further contact arm which is swivel-mounted in another space of the housing of the automatic circuit breaker.

6. Automatic circuit breaker as claimed in Claim 1, characterised in that a S torsion spring (16) is positioned over a boss through which the swivel axis passes, in that one leg of the torsion spring is hooked behind a hook on the passes, in that one leg of the torsion spring is hooked behind a hook on the pawl body and the other leg of the torsion spring is hooked behind a hook on the support plate, whereby the torsion spring biases the pawl body to produce a movement of said shoulder towards the projection on the lock pawl.

7. Automatic circuit breaker as claimed in any one of claims 2 to 6, characterised in that a bolt is secured in openings in the legs of the lock pawl and, and passes through openings in the support plate. and, and passes through openings in the support plate.

8. Automatic circuit breaker as claimed in Cla 7, characterised in that the bolt is guided through a housing wall of the automatic circuit breaker and coupled with a further contact arm which is swivel-mounted in another space of the housing of the automatic circuit breaker. DATED this 8th day of July 1996. FELTEN GUILLEAUME AUSTRIA AG WATERMARK PATENT TRADEMARK ATTORNEYS LEVEL 4, AMORY GARDENS 2 CAVILL AVENUE ASHFIELD NSW 2131 AUSTRALIA i LJD:AJ DOC 15 AU4157993.WPC e...e a e e a L Abstract An automatic circuit breaker has a movable switch bridge on which and opposite thereto is disposed a pivotable support plate Support plate pivotably bears a pawl arbor and a pawl which snap-lock together. Pawl is connected to a control knob (1) by means of a bail Bearing of pawl on support plate can be enlisted to actuate a contact position indicator and a further switch bridge. The release performance of the automatic circuit breaker is improved by means of support plate since pawl arbor and pawl are not borne directly on switch bridge in such a way that swi:ch bridge is unloaded. .°:oe o (Figure 4) *i 0 S «ee