The invention relates to a multi-spark gap for an overvoltage protector, with multiple electrodes and insulation elements arranged between the electrodes.
Multi-spark gaps have been known in a wide variety of designs from the state of the art and are used in the field of overvoltage protection. In particular, overvoltage protectors with spark gaps are used for protecting electrical devices or lines from overvoltages. The overvoltages can be caused by, for example, defects in systems or else also by lightning strikes. Multi-spark gaps have multiple individual spark gaps connected in series, which are formed by multiple stacked electrodes and insulation elements arranged between the electrodes. For example, the electrodes can be made of graphite, and the insulation elements can be produced by thin separating layers made of plastic. For this invention, the types of electrodes and insulation elements are not important factors.
Multi-spark gaps have the advantage that they have an improved power-follow current extinguishing capacity compared to individual spark gaps. The ability to extinguish the power-follow current is improved with an increasing number of individual spark gaps of the multi-spark gap. At the same time, the response voltage of the multi-spark gap increases with an increasing number of individual spark gaps.
In the state of the art, there are various possibilities for connecting the individual spark gaps to form a multi-spark gap. To this end, in most cases, the individual electrodes and insulation units are alternately stacked and secured by holding arrangements. For this purpose, the holding arrangements usually have at least two clamping elements and at least one connecting element, wherein the electrodes and insulation units are arranged between the clamping elements. The clamping elements can usually be braced against one another by the connecting element and thus clamp the electrodes and insulation units.
To influence the ignition behavior of a multi-spark gap, it is known from the state of the art to provide control circuits, wherein a control circuit has multiple passive control elements, and one control element each makes electrical contact with an electrode. In general, the first electrode of the multi-spark gap is not brought into contact. In some configurations known from the state of the art, moreover, the last electrode of a multi-spark gap is also not brought into contact. Frequently, capacitances, namely in particular capacitors, are used as control elements, wherein one capacitor each with a connector makes contact with an electrode, and all capacitors are connected in an electrically conductive manner to one another with their second connector. Contact between the control elements and the electrodes is made in this case usually on a lateral surface of the electrodes. Contact is associated with considerable expenditure. Moreover, the problem arises that with an increasing degree of integration in the case of multi-spark gaps, increasingly thinner electrodes are used. As a result, making contact in particular on the lateral surfaces of the electrodes is further impeded, in particular against the backdrop that necessary insulation intervals must be maintained.
The object of the invention is to indicate a multi-spark gap in which in a simple way, the individual electrodes of the multi-spark gap are held mechanically and are brought into electrical contact with one another, so that a compact design of the multi-spark gap is made possible.
The multi-spark gap according to the invention has a holding arrangement for mechanical holding and for making electrical contact with the electrodes of the multi-spark gap. To this end, the holding arrangement has at least a first electrically conductive clamping element, a second electrically conductive clamping element, and a first electrically conductive connecting element. The electrodes are arranged between the first clamping element and the second clamping element. The first clamping element makes electrical contact with the first electrode of the multi-spark gap; the second clamping element makes electrical contact with the last electrode of the multi-spark gap. In the state of the art, stacks of disk-shaped electrodes are often used, so that in such an implementation, the clamping elements are arranged on the front side of an electrode stack. The at least first connecting element of the holding arrangement mechanically connects the first clamping element and the second clamping element to one another. Furthermore, the at least first connecting element is electrically insulated from the first clamping element. Moreover, the at least first connecting element and the second clamping element are connected to one another in an electrically conductive manner.
The multi-spark gap according to the invention has a control circuit for controlling the ignition behavior of the multi-spark gap. To this end, the control circuit has multiple electrical control elements with respectively a first control element connector and a second control element connector. One control element each makes electrical contact—at least indirectly—with one electrode each (excluding the first electrode of the multi-spark gap) with its first control element connector. Moreover, the electrical control elements are connected to one another in an electrically conductive manner with their second control element connectors.
The multi-spark gap according to the invention is especially distinguished in that the second control element connectors of the electrical control elements of the control circuit are connected to one another electrically via the at least first connecting element of the holding arrangement.
Electrical contact among the electrodes is considerably simplified by the configuration according to the invention by using at least the first connecting element of the holding arrangement that is present in any case. Thus, a compact design of the multi-spark gap is made possible.
In an especially preferred configuration of the multi-spark gap according to the invention, the second control element connectors of the electrical control elements make contact with the connecting element via contact elements.
A preferred further development of the multi-spark gap according to the invention is characterized in that the contact elements are designed as spring elements. By using spring elements as contact elements, a more reliable electrical contact can be produced in a simple way. In particular, this is possible when the spring elements in a biased state are in the assembled state of the multi-spark gap. According to the invention, it is thus provided in one configuration that the spring elements in a biased state are in the assembled state of the multi-spark gap.
An especially preferred variant of the multi-spark gap is distinguished in that the spring elements can be brought into the biased state by assembling the multi-spark gap via the first connecting element. Thus, the process of making electrical contact is connected directly to the process of the mechanical mounting of the multi-spark gap, so that the required workload is reduced.
In order to facilitate contact among the spring elements and in particular to reduce the damages of the spring elements in mounting, in one configuration of the multi-spark gap according to the invention, the first connecting element has a ramped bias voltage area in the area of an insertion end. When assembling the multi-spark gap, the first connecting element is directed past the spring elements with the bias voltage area in such a way that the spring elements pass along the ramped bias voltage area and are biased.
Especially preferably, the first clamping element and the second clamping element have in each case at least one mounting recess for creating the first connecting element with its insertion end forward.
The first connecting element is especially preferably designed like a pin. Moreover, the connecting element, viewed from an insertion end, has, arranged in succession, an attaching area, a bias voltage area, and a contact area. The attaching area is used to attach the holding arrangement and the multi-spark gap in the assembled state. The attaching area is especially preferably designed as threading. This is advantageous to the extent that the holding arrangement can be attached by means of a screw nut that can be screwed onto the threading. In particular, the distance between the clamping elements can thus be regulated so that the electrodes clamped between the clamping elements can be clamped under optimal tension. The bias voltage area is used, as explained above, for prestressing the contact elements, namely preferably the spring elements during the mounting process. The contact area is used for making contact among the control elements in the assembled state of the multi-spark gap. In particular, the control elements are brought into contact via the contact elements, so that the contact area is used preferably for making contact among the contact elements.
According to the invention, the attaching area has a first cross-sectional area, and the contact area has a second cross-sectional area, wherein the second cross-sectional area of the contact area is larger than the first cross-sectional area of the attaching area. Also, the bias voltage area has a cross-sectional area that is constantly changing in the longitudinal direction of the connecting element, wherein the cross-sectional area of the bias voltage area increases from the first cross-sectional area of the attaching area to the second cross-sectional area of the contact area. By this configuration of the at least first connecting element, the mounting of the multi-spark gap is considerably simplified and made less susceptible to damage of the contact elements. The contact elements in general do not come into contact with the attaching area during the mounting but rather only with the bias voltage area. Because of the widening of the cross-section, prestressing of the contact elements is also done so that irreversible damage, for example by sudden bending, of the contact elements does not occur. The cross-sectional area of the bias voltage area especially preferably steadily increases from the first cross-sectional area of the attaching area to the second cross-sectional area of the contact area. Because of the steady widening of the cross-section, the risk of damage of the contact elements during prestressing is further reduced.
In one variant, the bias voltage area is designed as a chamfer. In an alternative variant, the bias voltage area has a cross section that widens convexly. In an alternative configuration, the bias voltage area has a cross section that widens concavely.
In order to promote the ignition of a multi-spark gap, it is known in the state of the art to provide ignition aids. As ignition aids, for example, ignition electrodes or resistive ignition elements are known from the state of the art. An especially preferred configuration of the multi-spark gap according to the invention has at least one ignition aid. The at least one ignition aid is arranged between the first electrode and the second electrode of the multi-spark gap and is used to ignite the multi-spark gap. In addition, the multi-spark gap has an ignition circuit for controlling the ignition aid. The holding arrangement of the configuration of the multi-spark gap according to the invention has a second electrically conductive connecting element, which mechanically connects the first clamping element and the second clamping element to one another. The second connecting element is insulated electrically from the first clamping element and is, moreover, insulated electrically from the second clamping element. According to the invention, the first connecting element also makes electrical contact with the ignition circuit. Moreover, the second connecting element makes electrical contact with the ignition circuit and the ignition aid.
In a preferred variant of the multi-spark gap according to the invention, the first connecting element has a contacting section for making electrical contact with the ignition circuit. Even more preferably, the contacting section is designed as a connecting element head. In particular, it is provided in a variant that on its side facing the connecting element, the connecting element head forms a contacting surface, which makes electrical contact with the ignition circuit in the assembled state of the holding arrangement. In an additional variant of the multi-spark gap according to the invention, the second connecting element has a contacting section for making electrical contact with the ignition circuit. Even more preferably, the contacting section is designed as a connecting element head. In particular, it is provided in a variant that the connecting element head of the second connecting element forms a contacting surface on its side facing the connecting element, which area makes electrical contact with the ignition circuit in the assembled state of the holding arrangement.
In a preferred variant that has a first connecting element and a second connecting element, the two connecting elements are identically configured.
Especially advantageous is a configuration in which the ignition circuit is arranged on an ignition board and in which the first connecting element and the second connecting element make electrical contact with the ignition board. For easy contact, in a quite especially preferred variant, the ignition board has two recesses, by which the connecting elements are produced in the assembled state of the holding arrangement in such a way that they rest with the contacting surface of the connecting element head on the ignition board and make contact with the ignition circuit.
To make contact with the ignition aid, in a preferred configuration, the ignition aid has a recess through which the second connecting element is run and thus makes electrical contact with the ignition aid.
It is also known from the state of the art to arrange the individual electrodes of a multi-spark gap in holding frames. The holding frames are then stacked on one another with enclosed electrodes. In a preferred variant of the multi-spark gap according to the invention, the electrodes of the multi-spark gap are arranged in holding frames. The holding frames also have first recesses for creating the first connecting element and—if a second connecting element is present—second recesses for creating the second connecting element. Moreover, the contact elements of the control elements extend into the first recesses, so that the first connecting element makes electrical contact with the contact elements in the first recesses.
In order to keep the installation space small, another configuration is characterized in that the control elements are arranged in the holding frame. To this end, one control element is provided per holding frame. Because of this configuration, it is no longer necessary to arrange the control elements on a separate board, which then has to be placed and brought into contact so that, on the one hand, mounting is facilitated, and, on the other hand, installation space is saved, so that a compact multi-spark gap can be achieved.
In particular, there are multiple options for configuring and further developing the multi-spark gap according to the invention. To this end, reference is made to the following description of preferred embodiments with reference to the accompanying drawings.
The holding arrangement 4 is used, on the one hand, for mechanical holding of the electrodes 2, and, on the other hand, for making electrical contact with the electrodes 2 of the multi-spark gap 1. The holding arrangement 4 has a first electrically conductive clamping element 5 and a second electrically conductive clamping element 6. Moreover, the holding arrangement 4 has an electrically conductive connecting element 7. The electrodes 2 are arranged between the first clamping element 5 and the second clamping element 6. The first clamping element 5 makes electrical contact with the first electrode 8 of the multi-spark gap 1. The second clamping element 6 makes electrical contact with the last electrode 9 of the multi-spark gap 1. The first connecting element 7 is designed to mechanically connect to one another the first clamping element 5 and the second clamping element 6. The first connecting element 7 and the first clamping element 5 are electrically insulated from one another. To this end, an insulation element 10 is provided, which extends at least partially into the mounting opening of the first clamping element 5. The first connecting element 7 and the second clamping element 6 are connected to one another in an electrically conductive manner. In this case, this is achieved in that both the first connecting element 7 as well as the first clamping element 5 and the second clamping element 6 are produced from an electrically conductive material, in this case a metal. The first connecting element 7 and the second clamping element 6 are in direct tangent contact with one another.
The multi-spark gap 1 has a control circuit 11 for controlling the ignition behavior of the multi-spark gap 1. To this end, the control circuit 11 has multiple electrical control elements 12, which in this case are designed as capacitors. The electrical control elements 12 in each case have a first control element connector 13 and a second control element connector 14. One control element 12 each is brought into electrical contact with one electrode 2 each with its first control element connector 13. Only the first electrode 8 is not connected to a control element 12. All electrical control elements 12 are connected in an electrically conductive manner to their second control element connectors 14. The electrically conductive connection of the second control element connector 14 is carried out via the at least first connecting element 7 of the holding arrangement 4 of the multi-spark gap 1. The holding arrangement 4 thus performs, on the one hand, the function of the mechanical holding of the multi-spark gap 1 and, on the other hand, the function of the electrodes 2 that make electrical contact via the control elements 12 of the control circuit 11. In the depicted embodiment of the multi-spark gap 1, the second control element connectors 14 of the electrical control elements 12 make contact with the first connecting element 7 via contact elements 15. The contact elements 15 are designed as spring elements 16. Moreover, the spring elements 16 are in a biased state in the assembled state of the multi-spark gap 1. The spring elements 16 are brought by the first connecting element 7 into the biased state by assembling the multi-spark gap 1.
As can be seen from
Various configurations of the insertion end 17 of the first connecting element 7 are depicted in
The second connecting element 27 is arranged in the holding arrangement in such a way that it makes electrical contact with the ignition circuit 24 and the ignition aid 22. The second connecting element 27 thus produces an electrical connection between the ignition circuit 24 and the ignition aid 22. The first electrically conductive connecting element 7 produces an electrically conductive connection between the second clamping element 6 and the ignition circuit 24. Moreover, the first connecting element 7 is used in addition for making electrical contact with the control elements. The control elements are not visible in
For making electrical contact with the ignition circuit 24, both the first connecting element 7 and the second connecting element 27 have an ignition circuit contacting section 32. The ignition circuit contacting section 32 is made on the end of the connecting elements 7, 27 opposite to the insertion end 17. The ignition circuit contacting section 32 is designed as a connecting element head 33 and forms a contacting surface 34 on its side facing the connecting element 7, 27, which surface in the assembled state of the multi-spark gap makes electrical contact with the ignition circuit 24. In the depicted configuration, the ignition circuit 24 is arranged on an ignition board 35. The first connecting element 7 and the second connecting element 27 accordingly make electrical contact with the ignition board, wherein to ensure easy contact in this case, the ignition board 35 has two recesses 36, by which the connecting elements 7, 27 are produced in the assembled state of the multi-spark gap. The two connecting elements 7, 27 rest with the contacting surface 34 of the connecting element head 33 on the ignition board 35.
The depicted multi-spark gap 1 has holding frames 37, in which the electrodes 2 are arranged. The holding frames 37 also electrically insulate the electrodes 2 from one another. The holding frames 37 are configured in such a way that they have first recesses 38 for creating the first connecting element 7 and second recesses 39 for creating the second connecting element 27. The contact elements 15, in this case the spring elements 16, of the control elements 12 extend into the first recesses 38 of the holding frame 37, so that the first connecting element 7 makes contact with the contact elements 15 in the recesses 38. In order to produce a multi-spark gap that is especially compact and can be brought into contact easily, the control elements 12 are arranged directly in the holding frame 37. The first connecting element 7 and the second connecting element 27 are attached with screw nuts 21 on their insertion ends 17 in the inserted state. Thus, the tension at which the electrodes 2 are clamped between the clamping elements 5, 6 can also be adjusted.
The first electrically conductive connecting element 7 and the second electrically conductive connecting element 27 are designed identically in this depiction. Moreover, the two connecting elements 7, 27 are arranged on opposite sides of the electrodes 2 in each case. Together with the first clamping element 5 and the second clamping element 6, the connecting elements 7, 27 frame the electrode stack that is formed from the electrodes 2. The first insulation element 28 is arranged on the side of the first clamping element 5 facing away from the electrodes 2. The ignition board 35 is arranged on the side of the first insulation element 28 facing away from the first clamping element 5. The second insulation element 29 is arranged on the side of the second clamping element 6 facing away from the electrodes 2. Moreover, both insulation elements 28, 29 have recesses through which the connecting elements 7, 27 are run.
Number | Date | Country | Kind |
---|---|---|---|
501964 | Apr 2022 | LU | national |
Number | Name | Date | Kind |
---|---|---|---|
20200044419 | Meyer et al. | Feb 2020 | A1 |
20200044442 | Meyer et al. | Feb 2020 | A1 |
Number | Date | Country |
---|---|---|
102018132088 | Jun 2020 | DE |
2615703 | Jul 2013 | EP |
Entry |
---|
DE 102018132088 Translation (Year: 2020). |
Number | Date | Country | |
---|---|---|---|
20230352915 A1 | Nov 2023 | US |