EP2027590B1 - Thermal and/or magnetic overload trip - Google Patents

Description

The invention relates to a thermal and magnetic overload release for a multi-pole electrical switching device.

Such an overload release, in which all the essential functional parts, including the adjusting elements, are arranged on or in a single housing part and which therefore forms a single pretestable unit is already known from EP 848 404 known. In this known overload release, the housing part accommodating the functional elements consists of an electrically insulating material, wherein each current path formed by busbars has a chamber-shaped housing area delimited by sidewalls and all tramways have a tripping shaft which can pivot about an axis of rotation. Upon reaching a predetermined thermal and / or magnetic limit, the trip shaft is pivoted so far against the restoring force of a spring from a rest position that it triggers a provided outside the housing part switching mechanism. To specify the thermal and magnetic limit two manually rotatable adjusting elements are provided, whose axes of rotation are arranged perpendicular to the axis of rotation of the trip shaft.

A disadvantage of this known overload release, inter alia, that its installation and possibly also its subsequent disassembly is relatively time consuming and costly. Because the functional elements of the overload release receiving housing part is formed in several parts and comprises a busbars of the individual current paths and the thermal and magnetic trip units and the trigger shaft receiving frame-shaped housing part and the two adjusting elements receiving separate carrier part, which are bolted to the frame-shaped housing part above the trip shaft got to. This separate support member also serves to support a second wave-shaped transmission element, which is rotated upon actuation of the magnetic limit setting element and acts via springs on the current paths associated armature.

From the DE 101 13 040 A1 a thermal overload release is also known for a multi-pole electrical switching device, wherein the tripping units are arranged in a front-side open two-part housing. However, essential functional parts are stored only loosely in the housing, so that a functional test of this overload release and its transport can be done only after the assembly of the switching device.

From the US 2005/024172 A1 a substantially magnetic overload release (residual current release) for a multi-pole electrical switching device is known. The functional parts of the known magnetic overload release, which comprise a tripping shaft, are arranged in an at least three-part housing. The functional parts are attached to at least two different walls of the housing, which are then only then connected to each other. Only after the connection of these walls is a positional fixation of the trip shaft, so that an exchange of a possibly faulty trip shaft is extremely time consuming.

With regard to the arrangement of functional parts for a thermal overload trip the above document no information can be found.

The invention has for its object to disclose a compact and constructed as possible thermal and magnetic overload release, which is a pre-testable transport-safe unit, which can be mounted in a simple manner and, if necessary, again disassembled.

This object is achieved by the features of claim 1. Further, particularly advantageous embodiments of the invention disclose the dependent claims.

The invention is based essentially on the idea that the housing of the overload release comprises a one-piece hood-shaped housing part, which accommodates all essential functional parts, including the adjusting elements, and which is at least partially closed by a detachable cover part on the front side.

For this purpose, the hood-shaped housing part is on the inside formed such that the functional elements from the front of this housing part from insertable and with the inner walls are positively or non-positively connectable. In this case, the hood-shaped housing part is preferably designed such that the triggering shaft, for example, after the attachment of the busbars to the rear wall of the hood-shaped housing part, is inserted into corresponding bearing points of the outer side walls of the housing part.

The respectively required for setting the thermal and / or magnetic limit adjustment is rotatably mounted in the roof wall of the hood-shaped housing part, such that it can be inserted from the outside of the roof wall and manually operated and interacts on the inside via connecting elements with the corresponding functional elements.

For a thermal overload trip in the hood-shaped housing part of each busbar is responsive to changes in temperature strip-shaped bimetallic element assigned, which is in operative connection via a first transmission element with the pivotable release shaft, such that upon occurrence of a thermal overload, the corresponding bimetallic element acts on the first transmission element on a first arm of the release shaft, so that it against the restoring force of a spring from its rest position in their actuation position is pivoted.

To set the respective thermal limit, a first adjusting element is rotatably mounted in the roof wall of the hood-shaped housing part, which engages over an eccentrically arranged pin-shaped extension in a recording of the trip shaft and this moves axially, so that the distance between the respective first transmission element and the opposite Area of the first arm of the trip shaft changed in a predeterminable manner.

Alternatively, it can also be provided that, for setting the respective thermal limit value, the first adjusting element acts on the eccentric pin-shaped extension in a recording of all strassenahnen a strip-shaped first transmission element and this moves axially, so that the distance between the respective bimetallic element and the first transmission element changed in a predeterminable manner.

For a magnetic overload trip each busbar is preferably associated with a pivotally arranged anchor which is movable in the overload case against the restoring force of a spring in the direction of a second arm of the trip shaft and pivots the trip shaft from its rest position to its actuated position.

To set the respective magnetic limit value, a second adjusting element is mounted in the roof wall, which acts on all the current paths associated, arranged parallel to the trigger shaft, rotatable second transmission element acts on the current paths associated anchor such that the distance between the respective armature and the second arm of the trip shaft is changeable in a predeterminable manner.

At the second transmission element advantageously a web-shaped control element is arranged, which in a corresponding contour of the second adjusting element engages, such that rotation of the second adjusting causes rotation of the second transmission element, wherein arranged on the transmission element arm-shaped actuating elements act on the busbar associated with the armature and press them in the direction of the second arm of the overload release.

The side walls of the hood-shaped housing part preferably have openings which are formed as bearing points for the end regions of the second transmission element.

The tripping shaft and / or the second transmission element are preferably an economically producible part made of an electrically insulating material (for example plastic or hard paper).

• Fig.1 die perspektivische Ansicht eines erfindungsgemäßen Überlastauslösers mit geöffnetem Gehäuse für ein dreipoliges Schaltgerät;
• Fig.2 einen Schnitt durch den in Fig.1 dargestellten Überlastauslöser entlang der dort mit II-II bezeichneten Schnittlinien, wobei das Gehäuse geschlossen ist,
• Fig.3 eine schematische Darstellung zur Erläuterung des Zusammenwirkens eines ersten Einstellelementes mit einer in dem Überlastauslöser angeordneten und in den Fig.1 und 2 mit 15 bezeichneten Auslösewelle; und
• Fig.4 einen Teilschnitt durch eine Seitenwand des Gehäuses im Bereich einer Lagerstelle des Endbereiches eines auf einen Anker wirkenden Übertragungselementes.

Further details and advantages of the invention will become apparent from the following, with reference to figures explained embodiments. Show it:

• Fig.1 the perspective view of an overload release according to the invention with an open housing for a three-pole switching device;
• Fig.2 a section through the in Fig.1 shown overload tripping along the designated there II-II cutting lines, the housing is closed,
• Figure 3 a schematic representation for explaining the interaction of a first adjustment with a arranged in the overload release and in the Fig.1 and 2 trigger shaft labeled 15; and
• Figure 4 a partial section through a side wall of the housing in the region of a bearing point of the end portion of an armature acting on an anchor element.

In Fig.2 1 denotes an inventive thermal and magnetic overload release for a three-pole electrical switching device. The overload release 1 comprises a housing 2 made of plastic. This consists essentially of a hood-shaped housing part 3 ( Fig.1 ) with a roof wall 4, a bottom wall 5, a rear wall 6 and two side walls 7, 8 for receiving all essential functional elements of the overload release 1 and a detachable cover part 9 (FIG. Fig.2 ) together. The cover part 9 consists of a first portion 9 'for closing the front side 38 of the hood-shaped housing part 3 and an angled second portion 9 "for partially covering the roof wall 4 of the hood-shaped housing part. 3

According to the number of poles of the switching device, three busbars 10 are passed through the housing 2 of the overload release 1, wherein each busbar 10 is assigned a limited by side walls chamber-shaped housing portion 11-13. All busbars 10 together in the upper region of the hood-shaped housing part 3 is associated with a pivotable about an axis of rotation 14 release shaft 15, which is preferably a one-piece plastic injection molded part. The trip shaft 15 is mounted in bearings 16 of the side walls 7, 8 of the hood-shaped housing part 3 and is pivoted upon reaching a predetermined thermal and / or magnetic limit from its rest position to an actuation position in which it triggers a corresponding switching mechanism (not shown).

For a thermal overload trip in the hood-shaped housing part 3 is attached to each busbar 10 responsive to changes in temperature strip-shaped bimetallic element 18 which is connected via a pin-shaped first transmission element 19 with the pivotable trip shaft 15 in operative connection, such that upon occurrence of a thermal overload, the corresponding bimetallic element 18 acts on the first transmission element 19 on a first arm 20 of the release shaft 15, so that it is pivoted from its rest position to its actuated position.

To set the respective thermal limit value, a first adjusting element 21 is rotatably mounted in the roof wall 4 of the hood-shaped housing part 3, whose axis of rotation 22 is perpendicular to the axis of rotation 14 of the trigger shaft 15 and which from the outside manually, for example by means of a screwdriver, can be actuated.

The first adjusting element 21 has off-center a pin-shaped extension 23 ( Figure 3 ), which engages in a fork-shaped receptacle 24 of the release shaft 15 and this axially displaces upon rotation of the first adjusting element 21, so that the distance between the respective first transmission element 19 and the (a wedge-shaped contour having) opposite surface of the first arm 20 of the trigger shaft 15 changed in a predeterminable manner. The bearings 16 of the trip shaft 15 in the side walls 7, 8 of the hood-shaped housing part 3 must therefore be chosen such that they allow a corresponding axial displacement of the trip shaft 15.

So that the overload release 1 according to the invention triggers even with a magnetic overload, an armature 25 is pivotably arranged on each busbar 10. When a magnetic overload occurs, this armature 25 is pivoted by the magnetic field located around the respective bus bar 10 against the tensile force of a spring 26 in the direction of a second arm 27 of the trip shaft 15. Upon actuation of the second arm 27, in turn, the trip shaft 15 is rotated from its rest position to its operating position and unlocks the switching mechanism, not shown.

To set the respective magnetic limit value, a second adjusting element 28 is rotatably mounted in the roof wall 4. This adjusting element 28 acts via an all busbars 10 associated, arranged parallel to the trip shaft 15, rotatable second transmission element 29 on the busbars 10 associated armature 25, so that upon rotation of the second adjusting element 28, the armature 25 against the tensile force of the springs 26 in the direction are pressed on the second arm 27 of the trip shaft 15 and the distance between the respective armature 25 and the second arm 27 of the overload release 1 is changed in a predeterminable manner.

For this purpose, on the one hand, a web-shaped control element 30 is arranged on the second transmission element 29, which engages in a corresponding contour 31 of the second adjusting element 28. On the other hand, the second transmission element 29 has arm-shaped adjusting elements 40, which act on the armature 25 and press it in the direction of the second arm 27 of the tripping shaft 15.

In order to avoid that the second transmission element 29 can move axially in its intended use, the wave-shaped end portions 32, 33 of the second transmission element 29 each have a radially extending stop cam 41. These stop cams 41 are projecting inwardly Wall portions 42 of the side walls 7, 8 of the housing 2, so that an axial displacement of the second transmission element 29 is not possible.

To introduce the two end portions 32, 33 in the bearing points 34, 35 during assembly of the second transmission element 29, the transmission element 29 is first brought into a mounting position in which the stop cam 41 are each opposite a wall portion 43 of the side walls 7, 8, the is reset relative to the wall portions 42 (see. Figure 4 in which the stop cam 41 located in the mounting position is indicated by dashed lines). This makes it possible that the second transmission element 29 may first be introduced, for example, in the bearing 34 and then moved relatively far to the left. Subsequently, the end portion 33 of the transmission element can then be inserted into the bearing 35 and then the transmission element 29 are rotated to its working position, in which the stop cam 41 are located in front of the wall portions 42.

Also, the second transmission element 29 is preferably a one-piece plastic injection molded part, the end portions 32, 33 are mounted in corresponding bearing points 34, 35 of the side walls 7, 8.

The assembly of the overload release 1 according to the invention is very simple. First, the busbars 10 must be used with the pre-assembled strip-shaped bimetallic elements 18 and first transmission elements 19, the anchors 25 and the springs 26 of the front side 38 of the hood-shaped housing part 3 and secured to the rear wall 6 by means of screws 36. Subsequently, the tripping shaft 15 and the second transmission element 29 are then also inserted from the front side 38 of the housing part 3 into the bearing points 16 and 34, 35 of the side walls 7, 8. Then, the two adjusting elements 21, 28 are inserted from above into the designated bearing points of the roof wall 4 and, if they do not already get when inserted into engagement with the corresponding connecting elements of the trigger shaft 15 and / or the second transmission element 29, connected to these elements.

Subsequently, the lid part 9 is then pushed onto the hood-shaped housing part 3 until both parts are connected to each other via clips 37. By the Dekkelteil 9 on the one hand, the front side opening 38 of the hood-shaped housing part 3 is closed and on the other hand, the adjusting elements 21, 28 secured against falling out and automatic rotation.

To disassemble the overload release 1, proceed in reverse order, i. it is first removed the cover part 9. Then, the adjusting elements 21, 28 are pulled upwards and the second transmission element 29 and the release shaft 15 are removed from the front. Finally, by removing the screws 36, the busbars 10 with the components attached thereto also removed from the front.

Of course, the invention is not limited to the embodiment described above. Thus, for example, be provided that the setting of the respective thermal limit, the first adjustment via the off-center pin-shaped extension in a recording of a all current paths associated strip-shaped first transmission element acts and this moves axially, so that the distance between the respective bimetallic element and the first transmission element changed in a predeterminable manner. In this case, the trip shaft need not be designed to be axially displaceable.

LIST OF REFERENCE NUMBERS

1

Overload release

2

casing

3

Hood-shaped housing part

4

roof wall

5

bottom wall

6

Back wall, wall

7.8

side walls

9

cover part

9 '

first subarea

9 "

second subarea

10

busbars

11-13

chamber-shaped housing areas

14

axis of rotation

15

tripping shaft

16

bearings

18

bimetallic

19

first transmission element

20

first arm

21

(first) adjusting element

22

axis of rotation

23

renewal

24

admission

25

anchor

26

feather

27

second arm

28

(second) adjustment

29

second transmission element

30

control

31

contour

32.33

end regions

34.35

bearings

36

screw

37

clips

38

Opening, front

40

arm-shaped control elements

41

stop cams

42

wall area

43

wall area

Claims (12)

1. Thermal- and magnetic-overload trip (1) for an electrical switching device having multiple poles, comprising a housing (2) which is assigned to the overload trip (1), is made of an electrically insulating material and has busbars (10) which are assigned according to the poles, wherein a chamber-like housing region (11-13) is assigned to each busbar (10) and is delimited by side walls, and a trip shaft (15), which is pivotable about an axis of rotation (14), is assigned to each busbar (10) and can pivot from a rest position into an operating position when a predeterminable thermal and/or magnetic threshold value is reached and triggers a corresponding switching mechanism, and wherein a manually rotatable adjusting element (21) is provided for specifying the thermal or magnetic threshold value, the axis of rotation (22) of which element is arranged so as to be approximately perpendicular to the axis of rotation (14) of the trip shaft (15), characterised in that
   the housing (2) for receiving all essential functional elements comprises a single-piece cap-shaped housing part (3) having a top wall (4), a bottom wall (5), a rear wall (6) and two external side walls (7, 8), the front of which housing part can be closed at least in part by means of a removable lid part (9),
   and wherein
   the inside of the cap-shaped housing part (3) is designed such that, with the exception of the adjusting element (21, 28), all essential functional elements can be inserted from the front (38) of the cap-shaped housing part (3) and can be connected to at least one of the walls of the cap-shaped housing part (3), wherein the end regions of the trip shaft (15) are rotatably mounted at mounting points arranged in the external side walls (7, 8) of the cap-shaped housing part (3), and wherein
   the adjusting element (21, 28) is rotatably mounted in the top wall (4) of the cap-shaped housing part (3) such that it can be manually operated from the outside of the top wall (4).
2. Overload trip according to claim 1, characterised in that, in order to trigger tripping in the event of thermal overload, a strip-shaped bimetallic element (18) which reacts to changes in temperature is assigned to each busbar (10) in the cap-shaped housing part (3) and is operatively connected to the pivotable trip shaft (15) by means of a first transmission element (19) such that, if a thermal overload occurs, the respective bimetallic element (18) acts on a first arm (20) of the trip shaft (15) by means of the first transmission element (19) so that said arm is moved from the rest position into an operating position.
3. Overload trip according to claim 2, characterised in that, in order to adjust the respective thermal threshold value, a first adjusting element (21) engages in a receptacle (24) of the trip shaft (15) by means of an eccentric pin-shaped projection (23) and axially displaces said shaft such that the distance between the respective first transmission element (19) and the opposite surface of the first arm (20) of the trip shaft (15) changes in a predeterminable manner.
4. Overload trip according to claim 2, characterised in that, in order to adjust the respective thermal threshold value, a first adjusting element (21) acts in a receptacle of the one strip-shaped first transmission element assigned to each busbar by means of an eccentric pin-shaped projection (23) and axially displaces said transmission element such that the distance between the respective bimetallic element (18) and the first transmission element changes in a predeterminable manner.
5. Overload trip according to any of claims 1 to 4, characterised in that, in order to trigger tripping in the event of magnetic overload, a pivotally arranged armature (25) is provided for each busbar (10) and moves towards a second arm (27) of the trip shaft (15), counter to the restoring force of a spring (26), in the event of overload and pivots the trip shaft (15) out of its rest position into its operating position, in which the switching mechanism is triggered.
6. Overload trip according to claim 5, characterised in that, in order to adjust the respective magnetic threshold value, a second adjusting element (28) is mounted in the top wall (4) and acts on the armatures (25) assigned to the busbars (10) by means of a rotatable second transmission element (29), which is assigned to each busbar (10) and arranged in parallel with the trip shaft (15), such that the distance between the respective armature (25) and the second arm (27) of the trip shaft (15) can be changed in a predeterminable manner.
7. Overload trip according to claim 6, characterised in that a web-shaped control element (30) is arranged on the second transmission element (29) and engages in a corresponding contour (31) of the second adjusting element (28) in such a way that a rotation of the second adjusting element (28) causes the second transmission element (29) to rotate, and in that that the second transmission element (29) is provided with arm-shaped actuators (40) which act on the armatures (25) and push them towards the second arm (27) of the trip shaft (15).
8. Overload trip according to either claim 6 or claim 7, characterised in that the side walls (7, 8) of the cap-shaped housing part (3) has openings designed as mounting points (34, 35) for the end regions (32, 33) of the second transmission element (29).
9. Overload trip according to claim 8, characterised in that the end regions (32, 33) of the second transmission element (29) each have a stop cam (41) which extends in the radial direction and abuts the inside of the side walls (7, 8) of the housing part (3) when the second transmission element (29) is in the assembled position and therefore prevents an axial displacement of the second transmission element (29).
10. Overload trip according to any of claims 1 to 9, characterised in that the trip shaft (15) and/or the second transmission element (29) are parts made of an electrically insulating material, such as plastics material or hard paper.
11. Overload trip according to any of claims 1 to 10, characterised in that the lid part (9) consists of a first portion (9') for closing the front (38) of the cap-shaped housing part (3) and an angled second portion (9") for covering the top wall (4) of the cap-shaped housing part (3) at least in part, such that the second portion (9") protects the adjusting elements (21, 28) from falling out.
12. Overload trip according to any of claims 1 to 11, characterised in that the cap-shaped housing part (3) and the lid part (9) are interconnected by means of at least one clip connection.

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