Title of Invention

LOW VOLTAGE CIRCUIT BREAKER

Abstract

The invention relates to a low voltage circuit breaker which comprises a Contact system for a principal current and an arc extinction chamber. An arc transmitting element is disposed between the contact system for the principal current and the arc extinction chamber. Said arc transmitting element (44) comprises at list One arc conductive element (46) which makes it possible to direct said arc in a certain manner to the arc extinction chamber (10).

Full Text

2002P13631WCUS PCT/DE03/02883 1 Description Low voltage circuit breaker The invention relates to a low voltage circuit breaker which comprises a contact system for a principal current and an arc 5 extinction chamber. An arc transmitting element is disposed between the contact system for the principal current and the arc extinction chamber. It is known that the size, particularly the width of contact systems for the principal current of low voltage circuit 10 breakers depends on a nominal current for which the low volt- age circuit breakers have been designed. The higher this nomi- nal current, the wider is the embodiment of the corresponding contact systems for a principal current. A disadvantage here is the fact that on the basis of strongly defined proximity 15 effects for wider contact systems for a principal current, a complicated arc extinction behavior is exhibited because the arc predominantly occurs at the edge of the wide contact sys- tems for a principal current and accordingly predominantly dwells in the edge zone of the arc extinction chamber allo- 20 cated to the contact systems for a principal current. As a re- sult, the cooling effect of the arc extinction chamber is only used in a limited manner. This leads to the fact that the arc is extinguished relatively late and the danger arises that ionized circuits may escape from the arc extinction chamber. 25 This burning off or down of the arcs in the edge zone occurs both during interruptions in the nominal current zone and dur- ing short-circuit interruptions of this low voltage circuit breaker. In order to make possible an explicit transmission of arcs 30 into arc extinction chambers, it is known from DE 35 39 673 A1 that an arc-conductive piece of a ferromagnetic material must be allocated Lo a contact system for a principal current by 2002P13631WCUS PCT/DE03/02883 2 means of which the arcs are to be explicitly transmitted to the arc extinction chamber. The disadvantage of this arrange- ment is the fact that additional components must be provided which are directly connected to the contact systems for a 5 principal current. This complicates the structure of the low voltage power switch and low manufacturing and/or assembly tolerances already lead to a failure when the arcs are con- ducted away. Therefore, it is the object of the invention to create a low 10 voltage circuit breaker according to said type in the case of which arcs defined in an arc extinction chamber can be trans- mitted in a simple manner. According to the invention, this object of the invention is achieved by means of a low voltage circuit breaker with the 15 features mentioned in Claim 1. Because said arc transmitting element disposed between the contact system for a principal current and the arc extinction chamber comprises at least one arc conductive element which makes it possible to direct said arc in a defined manner to the arc extinction chamber, it is 20 advantageously achieved that the arc is directed away from the contact systems for a principal current to be protected against burning down, and that a shorter arc extinction period is reached. This results in decreasing the stress on both the contact systems for a principal current, on the one hand, and 25 the arc extinction chamber, an the other hand, because these basically can now, by means of a defined start-up by the arc, convert their arc extinction capacity with a high degree of effectiveness. It has been proven that by providing simple arc conductive elements to the arc transmitting element, it is 30 possible to direct the area in a defined manner. Changes to the contact system for the principal current itself need not be made so that the modifications according to the invention ate only limited to the arc transmitting element alone. As a 2002P13631WCUS PCT/DE03/02883 3 result, the solution according to the invention is very simple and can therefore also be implemented cost-effectively in mass-produced low voltage circuit breakers. In a preferred embodiment of the invention provision is made 5 so that at least one arc conductive element extends at an an- gle to an imagined vertical line of the arc transmitting ele- ment away from an edge zone in the direction of a middle zone. - This advantageously results in the fact that the arc is di- rected via at least one arc conductive element approximately 10 into the middle of the arc extinction chamber so that the de- sired arc extinction effect can be very securely achieved. In a further preferred embodiment of the invention provision is made so that the arc conductive element has at least one running edge basically running parallel to the arc transmit- 15 ting element. - As a result of this an optimum arc position can be controlled within the arc extinction chamber in a de- fined manner. - The running edge can be formed by a sharp- edged transition of a step. In addition, in a preferred embodiment of the invention provi- 20 sion is made so that the arc conductive element particularly has several running edges running at different angles to the imagined vertical line. - By means of such a ray-shaped system, of the running edges on the arc transmitting element, the arc is directed safely into the middle zone of the arc extinction 25 chamber independent of the point of origin of the arc. In a further preferred embodiment of the invention provision is made so that the arc conductive element is non-positively connected to the arc transmitting element. As a result of this, the arc conductive element can be embodied in a simple 30 fashion. This only requires the manufacturing of an arc con- ductive element with a simple design - for example, as a crown-shaped stamped part - and the fixing of this arc conduc- 2002P13631WCUS PCT/DE03/02883 4 tive element to the arc transmitting element - for example, by means of welding. In the case of a correspondingly selected system of pronged rays of the crown-shaped stamped part, the running edges can be determined for the arc in a simple way. 5 In this way, particularly the different sizes of the arc ex- tinction chambers can be adapted easily. The rays preferably have two running edges for the arcs running at right angles to one another which run front the edge zone of the arc transmit- ting element into the middle of the arc extinction chamber. As 10 a result of this, depending on the point of origin and the in- tensity, it is possible to direct said adapted arc to the arc extinction chamber. The arc conductive element connected non-positively to the arc transmitting element in addition offers the advantage that a 15 bigger cooling body is available in the zone of the arc trans- mitting element which favorably influencs the extinction be- havior of the arc extinction chamber. At least one section of a wire, particularly a steel wire can also serve as an arc conductive element. 20 According to a further preferred embodiment of the invention provision can be made for at least one arc conductive element being embodied as a profile part stamped from the plane of the arc transmitting element. This simplifies manufacturing of an arc transmitting element that features arc conductive ele- 25 ments. At least one end place of a stack of extinction sheets can be used advantageously as an arc transmitting element. Further preferred embodiments of the invention can be found in the other features mentioned in the subclaims. 30 Other advantageous further developments of the invention are 2002P13631WCUS PCT/DE03/02883 5 explained below on the basis of the accompanying drawings. They are as follows: Figure 1 partial sectional view through a low voltage circuit breaker; 5 Figure 2 view from above of an arc transmitting element; Figure 3 sectional view through the arc transmitting element; Figure 4 enlarged detailed view of the arc transmitting ele- ment and Figure 5 schematic perspective view of an arc transmitting 10 element. Figure 1 shows pare of a sectional view of an arc extinction chamber 10 of a low voltage circuit breaker 12. The low volt- age circuit breaker 12 is embodied for a relatively high nomi- nal current, for example, 1000 A. 15 A contact system for a principal current 14 of the low voltage circuit breaker 12 comprises a fixed principal contact 16 with a contact facing 18 as well as a movable principal contact 20 with a contact facing 22. If required, these principal con- tacts 16 and 20 are provided repeatedly in a parallel system. 20 The higher the nominal current, the wider is — according to the view into the paper plane - the embodiment of the contact system for a principal current. The principal contacts 16 and 20 are used for the arc-free transmission of the permanent current of the low voltage cir- 25 cuit breaker 12 in the closed state of the principal contacts 15 and 20. The contact system for a principal current 14 also comprises a fixed blow-out contact 24 with a contact facing 26 and a mov- able blow-our contact 28 with a contact facing 30. Arc horns 2002P13631WCUS PCT/DE03/02883 32 or 34 are allocated to the blow-out contacts 24 and 28. An insulating coupling 36 serves for connection to a driving arrangement and reset device (not shown) in order to open and close the contact system for a principal current 14. 5 The arc extinction chamber 10 comprises a housing 38 which en- closes an inner space 40 serving an arc extinction. In the in- ner space 40, a stack of extinction sheets 41 consisting of extinction sheets 42, 43 is arranged in a known way. An arc transmitting element 44 limits the inner space 40 of its fixed 10 contact side. In principle, the arc transmitting element 44 is embodied plate-shaped and carries on its side facing the inner space 40, an arc conductive element 46 whose structure will be explained in greater detail below on the basis of the follow- ing drawings. The arc gases (switching gases) formed in the 15 course of the extinction process escape from the arc extinc- tion chamber 10 through an outlet 50, provided on the top side, subdivided into passages 48; said gases escaping in the direction of the arrows 52. In addition, a further switching gas damper can be arranged at the top side of the arc extinc- 20 tion chamber 10. The arc conductive element 46 is arranged in the vicinity of the arc transfer points from the arc horn 32 to the arc trans- mitting element 44. Figure 2 shows a view from above of an arc transmitting ele- 25 ment 44 which clearly shows the arrangement of the arc conduc- tive element 46 on the arc transmitting element 44. The arc conductive element 46 is arranged non-positively as an addi- tional part on the surface of the arc transmitting element 44 and spot welded to it or joined using a similar method. Ac- 30 cording to a further embodiment, the arc conductive element 46 can be stamped from the plane of the arc transmitting element 44. 2002P13631WCUS PCT/DE03/02883 7 The arc conductive element 46 comprises running edges 54 which form the side limit of ray-shaped prongs 56. In this case, the running edges 54 run at different angles in each case to an imagined vertical line 58 through the arc transmitting element 5 44. In this case, the running edges 54 are embodied in such a way that they run from a bottom edge zone in the direction of the top middle zone of the arc transmitting element 44. The sectional view in Figure 3, as well as the enlarged de- tailed view in figure 4, show that the running edges 46 are 10 formed by steps 60 running basically vertically to the plane of the arc transmitting element 44 so that there is a sharp- edged transition 62 on the surface of the arc conductive ele- ments 46. Figure 5 in a perspective view again shows the plastic procru- 15 sion of the arc conductive element 46 on the arc transmitting element 44 . This results in an embodiment of the running edges 54 as sharp-edged transitions 62 of the steps 60. The number of arc conductive elements 46 as well as the number of running edges 54 can be adapted to the design of the low 20 voltage circuit breaker l2, particularly to the arc extinction chamber 10. The ray-shaped running edges 54 running from the edge zones of the arc extinction chember 10 into the middle zone of the arc extinction chamber 10 lead to the arcs originating in the edge 25 zone at the contact system for a principal current 14 being safely directed into the middle zone of the arc extinction chamber 10 where these are extinguished particularly effec- tively. Because of the system of an arc conductive element 46 in the transfer zone of the arc horn 32 on the arc transmit- 30 ting element 44, the arcs can be directed particularly well into the middle zone of the arc extinction chamber 10. 2002P13631WCUS PCT/DE03/02883 8 Each one of the two end plates 43 of the stack of extinction sheets 41 can be used as an arc transmitting element and as a result be provided with an arc conductive element. According to further embodiments which are not shown, instead 5 of the shown arc conductive element 46 which either has a crown-shaped or neck-shaped embodiment, provision can also be made for the running edges 54 being formed from welded-on in- dividual elements, for example, steel wire or the like. How- ever, the system of a relatively large additional part which 10 embodies a plurality of running edges 54, at the same time, leads to an embodiment of an additional mass which has a cool- ing effect on the arcs at a very early point in time for the switching-off process of the low voltage circuit breaker 12 so that a further improvement of the extinction behavior is 15 achieved. 2002P13631WCUS PCT/DE03/02883 9 Patent claims 1. Low voltage circuit greater with a contact system for a principal current and an arc extinction chamber in which case an arc transmitting element is disposed between the contact 5 system for the principal current and the arc extinction cham- ber, characterised in that the arc transmitting element (44) comprises at least one arc conductive element (46) which makes it possible to direct said arc in a defined manner to the arc extinction chamber (10). 10 2. Low voltage circuit breaker according to claim 1, charac- terized in that at least one arc conductive element (46) ex- tends at an angle to an imagined vertical line (58) of the arc transmitting element (44) away from an edge zone in the direc- tion of a middle zone. 15 3. Low voltage circuit breaker according to one of the previ- ous claims, characterized in that the arc conductive element (46) has at least one running edge (54) running basically par- allel to the arc transmitting element (44). 4. Low voltage circuit breaker according to one of the previ- 20 ous claims, characterized in that at least one running edge (54) can be formed by a sharp-edged transition (62) of a step (60). 5. Low voltage circuit breaker according to one of the previ- ous claims, characterized in that the arc conductive element 25 (46) particularly has several running edges (54) running at different angles to the imagined vertical line (58). 6. Low voltage circuit breaker according to one of the previ- ous claims, characterized in that the arc conductive element (46) is non-positively connected to the arc transmitting ele- 30 merit (44). 2002P13631WCUS PCT/DE03/02883 10 7. Low voltage circuit breaker aopordirug to claim 6, charac- terized in that the arc conductive element (46) is embodied as a crown-shaped stamped part. 8. Low voltage circuit breaker according to claim 6, charac- 5 terized in that the arc conductive element (46) is formed from at least one section of a wire, particularly a steel wire. 9. Low voltage circuit breaker according to one of the previ- ous claims, characterized in that at least one arc conductive element (46) is embodied as a profile part stamped from the 10 plane of the arc transmitting element (44) . 10. Low voltage circuit breaker according to one of the previ- ous claims, characterized in that at least one extinction sheet (42) or end plate (43) of a stack of extinction sheets (41) serves as the arc transmitting element. The invention relates to a low voltage circuit breaker which comprises a Contact system for a principal current and an arc extinction chamber. An arc transmitting element is disposed between the contact system for the principal current and the arc extinction chamber. Said arc transmitting element (44) comprises at list One arc conductive element (46) which makes it possible to direct said arc in a certain manner to the arc extinction chamber (10).

Documents:

00967-kolnp-2005-abstract.pdf

00967-kolnp-2005-claims.pdf

00967-kolnp-2005-description complete.pdf

00967-kolnp-2005-drawings.pdf

00967-kolnp-2005-form 1.pdf

00967-kolnp-2005-form 2.pdf

00967-kolnp-2005-form 3.pdf

00967-kolnp-2005-form 5.pdf

00967-kolnp-2005-international publication.pdf

967-KOLNP-2005-FORM-27.pdf

967-kolnp-2005-granted-abstract.pdf

967-kolnp-2005-granted-claims.pdf

967-kolnp-2005-granted-correspondence.pdf

967-kolnp-2005-granted-description (complete).pdf

967-kolnp-2005-granted-drawings.pdf

967-kolnp-2005-granted-examination report.pdf

967-kolnp-2005-granted-form 1.pdf

967-kolnp-2005-granted-form 18.pdf

967-kolnp-2005-granted-form 2.pdf

967-kolnp-2005-granted-form 3.pdf

967-kolnp-2005-granted-form 5.pdf

967-kolnp-2005-granted-gpa.pdf

967-kolnp-2005-granted-reply to examination report.pdf

967-kolnp-2005-granted-specification.pdf

967-kolnp-2005-granted-translated copy of priority document.pdf

967-KOLNP-2005-OTHER PATENT DOCUMENT.pdf