The invention relates to a holding arrangement for multiple electrodes, with at least two holding frames, which can be stacked flat one on top of another. In addition, the invention also relates to an arrangement of at least two stack spark gaps, each of which has multiple electrodes and frame-like insulators that are arranged between the electrodes.
Stack spark gaps, which are sometimes also referred to as multiple spark gaps, have been known for years. Such stack spark gaps consist of multiple electrodes and multiple insulators, which are arranged between the individual electrodes, so that an insulator, which has an opening in the center, is located in each case between two electrodes, so that two electrodes form a spark gap. In this case, the electrodes are in general designed as circular or rectangular graphite disks, between which correspondingly ring-shaped or frame-like insulators are then arranged. In this case, the insulators are often designed as thin insulating films made of plastic, for example, PTFE, and have a thickness of in general less than 1 mm.
From experience, various variants are known, such as ones in which the individual electrodes and the individual insulators can be connected to form a stack spark gap. Often, large-surface contact plates are used for this purpose, which plates form the front sides of the stack spark gaps and are twisted over multiple guide rods in the axial direction by being screwed together, so that the individual electrodes and the individual insulators are clamped in their stacklike arrangement between the contact plates. When the guide rods that are arranged between the contact plates are rerouted outside of the individual electrodes, this results in that the required installation space is relatively large.
A stack spark gap is known from German Utility Model DE 20 2013 102 647 U1, in which the installation space or space requirement is reduced in such a way that the individual electrodes are pierced in the center, and the contact plates that are arranged on the front sides of the stacked electrodes are connected to one another by a guide rod, which extends into the hole of the individual electrodes and the hole of the ring-shaped insulators. By using only one guide rod and its internal arrangement, a stack spark gap can be produced, whose space requirement is not significantly larger than the space requirement of the stacked electrodes.
Also, in this case, however, an exact positioning of the electrodes and insulators under one another is relatively complex. Moreover, there is the danger that over time, shifting between the individual elements can occur if the guide rods are not screwed down firmly enough. This danger is further increased by the fact that when pulse currents are diverted, elevated mechanical and thermal stresses occur, which can cause shifting between the individual elements. If the guide rod is screwed down or pulled excessively, however, twisting within electrodes that are produced on the basis of graphite can occur, which can have an unfavorable effect on the diversion capacity, the insulation strength, as well as the secondary current quenchability of the spark gaps. The cost of installing and arranging the individual electrodes and insulators is correspondingly increased in this case when multiple stack spark gaps are to be arranged in a surge protection system or a surge protection device.
The object of this invention is therefore to indicate a holding arrangement for multiple electrodes, by which multiple stack spark gaps can be built up in a simple and reproducible way. In this case, as high a flexibility as possible relative to the number of electrodes of a stack spark gap is to be provided.
This object is achieved in the case of the above-described holding arrangement in such a way that in the individual holding frames, at least two recesses are formed next to one another in each frame, whereby each of the recesses is used to accommodate a respective electrode, for which purpose the contour of the individual recesses is matched to the outside dimensions of the individual electrodes. In order to be able to easily position the individual holding frames that can be stacked flat one on top of another, the individual holding frames can be connected to one another mechanically.
The holding arrangement according to the invention, which comprises multiple holding frames that can be stacked one on top of another and that can be locked together, is thus distinguished first of all in that the individual holding frames are designed not only to accommodate an electrode, but also to accommodate at least two electrodes, preferably three electrodes, for which purpose a corresponding number of recesses for the individual electrodes are formed in the individual holding frames. Thus, 15 electrodes can be arranged in a holding arrangement that is formed of, for example, five holding frames, which in each case has three recesses, whereby in each case, five electrodes that are arranged one on top of another form a stack spark gap, so that three stack spark gaps that are arranged parallel to one another can be built up with such a holding arrangement. Because of the stackability, in this case great flexibility relative to the number of holding frames is possible, which frames form a holding arrangement. The number of holding frames is freely selectable depending on the application and operating conditions.
According to a preferred configuration of the holding arrangement according to the invention, in each case, a number of openings corresponding to the number of recesses are formed in the individual holding frames, which openings are connected to a respective recess, so that an electrode that is arranged in a recess can be contacted from the outside through the opening. In this case, the opening can optionally be sized so that components for controlling the electrical behavior of the individual stack spark gaps are also arranged completely or partially in the opening. Preferably, the openings are sized so that spring contacts through the openings contact the individual electrodes, whereby the spring contacts on the side that faces away from the electrodes are connected with a switch or corresponding components, for example components for controlling the ignition behavior.
Preferably, in this case, the openings are formed on at least one longitudinal side of the holding frame, so that the switches or the components, which contact the electrodes, can be arranged adjoining the longitudinal side of the holding frame. In this case, it is especially advantageous when all openings are arranged on one longitudinal side of the holding frame, since then the components for contacting the electrodes can be arranged especially simply on a common switch or a common printed circuit board that is positioned adjoining the longitudinal side of the holding frame.
At the outset, it was explained that in the case of the holding arrangement according to the invention, the individual holding frames can be positioned simply relative to one another by ensuring that the holding frames can be connected to one another. There are various possibilities relative to the configuration of the connection between the individual holding frames. For example, each of the holding frames can have at least one latching element on the front and at least one corresponding mating latching element on the rear, so that the latching element of a holding frame engages in a mating latching element of a second holding frame when the two holding frames are stacked one on top of another. For example, pin-shaped studs or projections as latching elements and mortises or recesses corresponding thereto as mating latching elements can be formed on the sides that are opposite to one another—front and rear—of the holding frames.
According to an especially preferred configuration of the holding arrangement, in each case a projection and, adjacent thereto, a set-back are formed on at least one side of the holding frame, whereby the projection extends above the plane of the holding frame in the direction of the adjacent holding frame and extends above the corresponding set-back of the adjacent holding frame when two holding frames are stacked one on top of another. In each case, a projection and a set-back are preferably formed here not only on one side of the holding frame, but rather on two sides that are opposite to one another, in particular on the two sides of the holding frame, so that a type of interlacing is produced by the interlocking of projections and set-backs of adjacent holding frames, which interlacing keeps the holding frames from sliding under one another.
So that the holding frames cannot slip relative to one another in the plane of the holding frames, preferably also at least one projection and, adjacent thereto, a set-back are formed on at least one longitudinal side. The projections on the longitudinal sides and the projections on the ends in this case preferably extend in opposite directions above the plane of the holding frames. By this type of interlacing, in addition, an exact positioning of the individual holding frames relative to one another is ensured, without the stacking of the holding frames being hampered.
In order to further simplify the stacking or joining together of the individual holding frames, gripping surfaces are preferably made on the individual projections, so that a holding frame can be easily gripped with two fingers by a mechanic and can be connected to another holding frame.
As has been explained above, individual stack spark gaps in general consist not only of multiple electrodes that are arranged one on top of another, but, moreover, also of multiple insulators, which are arranged between the individual electrodes. Therefore, the holding frames of the holding arrangement according to the invention have an at least partially circumferential edge which, according to an especially preferred configuration, is used as a seating for at least one frame-shaped insulator. Relative to the at least partially circumferential edge, the recesses are arranged set back in the holding frame, so that the frame-shaped insulator primarily rests on the edge and not on the electrodes that are arranged in the recesses. As a result, the position of the frame-shaped insulator is determined by the holding frame and is not dependent upon possible tolerances relative to the arrangement of the electrodes in the recesses. Since the edge is used as a seating for the frame-shaped insulator, it is not necessary that the edge is made completely circumferential. Gaps can thus be arranged in the edge, for example produced by the openings that are formed in the holding frame for contacting the electrodes.
For simple and exact positioning of the individual holding frames relative to one another, the above-described variants of the latching, in particular the forming of projections and set-backs, are sufficient. In order to connect the individual holding frames permanently and securely to one another, fastening elements are preferably provided, in which these can be screws or bolts. For arranging or accommodating at least one fastening element, in each case at least one hole for creating the fastening element is arranged in the individual holding frames. The holes in the individual holding frames are in this case aligned relative to one another when the holding frames are stacked one on top of another, i.e., the holes are formed at the same position in all holding frames. Preferably, in this case, at least two holes are formed in the individual holding frames, which holes are arranged in the sections of the holding frames between two recesses.
According to a final advantageous further development of the invention, which in addition is to be briefly explained here, at least one hole on one side (front or rear) of the holding frame is surrounded by a ring-shaped groove. On the opposite side (rear or front) of the holding frame, a ring-shaped projection subsequent to the hole is then formed, which projection extends above the plane of the holding frame in the direction of the adjacent holding frame, so that the ring-shaped projection engages in the ring-shaped groove of the adjacent holding frame when two holding frames are stacked one on top of another. Because of such a configuration, an interlacing of the holes of adjacent holding frames relative to one another is also carried out, thus ensuring that the reliable positioning of the individual holding frames relative to one another is further enhanced. In addition, the design of ring-shaped groove and ring-shaped projection on the holes produces an increase in air and creep distances.
In addition to a holding arrangement for multiple electrodes, this invention also relates to an arrangement of at least two stack spark gaps, which in each case have multiple electrodes and frame-like insulators that are arranged between the electrodes. In the case of such an arrangement, the above-mentioned object is achieved with the features of claim 10, in such a way that the individual electrodes and the individual insulators are arranged in the holding frame of the holding arrangement according to the invention. In this case, one electrode per stack spark gap and one insulator are respectively arranged in a holding frame, and multiple holding frames are stacked one on top of another. If this is an arrangement of, for example, three stack spark gaps, three electrodes and at least one insulator are arranged in each holding frame. In this case, the electrodes are arranged respectively in the recesses in the holding frame, while the insulator is accommodated in at least one partially circumferential edge of the holding frame.
Relative to the advantages of such an arrangement of at least two, preferably three, stack spark gaps, reference is made to the above-described advantages in connection with the holding arrangement according to the invention.
In principle, in the individual holding frames, a number of individual insulators corresponding to the number of electrodes could be provided, so that a separate frame-shaped insulator is to be assigned to each electrode. Preferably, however, in each case, only one frame-shaped insulating film is provided for each holding frame as insulation, in which film a number of recesses corresponding to the number of electrodes is formed, which recesses are arranged corresponding to the individual electrodes. By using only one frame-shaped insulating film instead of multiple individual insulators for each holding frame, the assembly of the arrangement is further simplified.
The insulating film preferably is made of a plastic, for example, PTFE, and has a relatively small thickness of preferably less than 1 mm, in particular less than 0.5 mm. In principle, however, other insulating materials for the insulating film are also possible. Likewise, the insulating film can also have a somewhat larger thickness, so that the insulating film then can also be referred to as an insulating disk or insulation plate. The term insulating film is thus to be limited neither to specific materials nor to a specific thickness.
In general, there are a large number of possibilities for further developing and configuring the holding arrangement according to the invention as well as the arrangement of at least two stack spark gaps. To this end, reference is made to the description of preferred embodiments in conjunction with the accompanying drawings.
The figures show a holding arrangement 1 for multiple electrodes 2, whereby the holding arrangement 1 has at least two holding frames 3, which are stacked flat one on top of another. Such an individual holding frame 1 is depicted in
In order to be able to connect the individual holding frames 3 to one another or to latch them, in each case a projection 8 and, adjacent thereto, a set-back 9 are formed on the two front sides 7 of the holding frame 3. The projections 8 in this case extend above the plane of the holding frame 3 in the direction of the adjacent holding frame 3. In the depiction according to
In addition to the projections 8 that are formed on the two ends 7 of the holding frame 3, the holding frame 3 also has two projections 10 on a longitudinal side 6, adjacent to which projections in each case a set-back 11 is formed. In the depiction according to
For simple handling of the individual holding frames, gripping surfaces 12 are made on the projections 8, which are formed on the front sides 7, so that a holding frame 3 can be easily grasped with two fingers by a mechanic. In this way, the stacking of the individual holding frames 3 one on top of the other is further simplified.
As is evident in particular from looking at
So that the individual holding frames 3 of the holding arrangement 1 can also be attached to one another perpendicular to the plane of the holding frames 3, in each case multiple holes 15 are arranged in the individual holding frames 3 for creating corresponding fastening elements (not depicted), whereby the holes 15 in the individual holding frames 3 align relative to one another when the holding frames 3 are stacked one on top of another. As fastening elements, in particular screws or rivets can be used. As is evident, for example, from
Moreover, the holding frames 3 have two additional recesses 21—seen from the front 16—which form additional projections on the rear 18, which extend above the plane of the holding frame 3. In the case of holding frames 3 that are stacked one on top of another, the recesses 21 and corresponding projections of two adjacent holding frames 3 engage in one another.
Since, in each case, only one insulator that is designed as insulating film 14 is arranged in the individual holding frames 3, the individual insulating films 14 in each case have a number of recesses 19 corresponding to the number of electrodes 2, which are arranged corresponding to the electrodes 2 or to the recesses 4 in the holding frame 3. In the depicted embodiment of a holding frame 3, which is provided for accommodating three electrodes 2, three recesses 19 are thus also arranged in the insulating film 14, as is evident from
Number | Date | Country | Kind |
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10 2018 118 898.6 | Aug 2018 | DE | national |