Overvoltage protection arrangement having a plurality of planar varistors arranged on a first side of an N-cornered supporting plate

Abstract

The invention relates to an overvoltage protection arrangement having: a plurality of planar varistors 2, 21, 22, which are arranged on a first side of a supporting plate 7; at least one gas arrester 10; and at least one thermal disconnection device, which is in close thermal contact with at least one of the varistors. The aforementioned components are surrounded by an outer housing 1, and electrical connection means 6, 61 for soldering to a printed circuit board are also provided on the second side of the supporting plate. The varistors 2, 21, 22 have a parallel stack arrangement, which is delimited on each of two opposing sides by an insulating partition wall 3, 31 which can be attached to the supporting plate. Each partition wall has at least one opening for a varistor terminal (62), each varistor terminal being connected to a thermal disconnection device, which in turn comprises a spring-loaded disconnecting lever (80), the respective disconnecting lever being connected at its first end to the respective varistor terminal by a soldered connection (18) and wherein its second end merges into one of the electrical terminals 6, 61 and penetrates through the supporting plate 7. The thermal disconnection device also has an insulating slide 4, whose free end acts on the disconnecting lever (80), wherein the slide runs in recesses in the respective partition wall 3, 31, and a change in the position of the slide can be seen by means of a viewing opening 8 in the outer housing 1.

Claims

1. Overvoltage protection arrangement having a plurality of planar varistors (2; 21;22) arranged on a first side of an n-cornered supporting plate (7), at least one gas arrester (10) and at least one thermal fuse or thermal disconnection device, wherein the at least one thermal fuse or thermal disconnection device includes a first thermal disconnection device which is in close thermal contact with at least one of the varistors, the aforementioned components being surrounded by an outer housing (1) and electrical terminals being provided on a second side of the supporting plate (7) for soldering on a printed circuit board, characterized in that the varistors (2; 21; 22) form a parallel stack arrangement which is delimited on two opposite sides by one insulating partition wall (3; 31) each, which can be attached to the supporting plate (7), each partition wall (3; 31) has at least one opening for a varistor terminal (62), which is connected to the first thermal disconnection device, which in turn comprises a spring-loaded disconnecting lever (80), the respective disconnecting lever (80) being at its first end connected with the respective varistor terminal (62) by a soldered connection and wherein its second end merges into one of the electrical terminals (6) and penetrates through the supporting plate (7), the first thermal disconnection device has an insulating slide (4), whose free end acts on the disconnecting lever (80), wherein the slide (4) runs in recesses (81) of the respective partition wall (3; 31) and a change of position of the slide (4) can be seen by means of a viewing opening (8) in the outer housing (1), characterized in that the at least one gas arrester (10) has a second thermal disconnection device, wherein the second thermal disconnection device is a thermal and spring force supporting disconnection device, characterized in that the thermal and spring force supporting disconnection device for the at least one gas arrester (10) comprises at least one torsion spring (9).

2. Overvoltage protection arrangement according to claim 1, characterized in that the stack arrangement is formed by three varistors (2; 21; 22) with their longitudinal sides adjoining each other.

3. Overvoltage protection arrangement according to claim 1, characterized in that the slide (4) has two pins for guiding reception of one spring element each, wherein the pins run in parallel.

4. Overvoltage protection arrangement according to claim 1, characterized in that the at least one gas arrester (10) is located on a partition-free side, which is electrically connected to the varistor stack arrangement.

5. Overvoltage protection arrangement according to claim 1, characterized in that the outer housing (1) is connectable to the supporting plate by means of a snap-in locking arrangement (13; 14).

6. Overvoltage protection arrangement according to claim 1, characterized in that the slide (4) engages in close proximity to the soldered connection between the disconnecting lever (80) and the varistor terminal (62).

7. Overvoltage protection arrangement according to claim 1, characterized in that the at least one thermal fuse or thermal disconnection device is of double and symmetrical design.

8. Overvoltage protection arrangement according to claim 1, characterized in that web faces (71) extending from the first side of the supporting plate (7) into sections of an enclosed space to ensure sufficient electrical separation distances.

9. Overvoltage protection arrangement according to claim 1, characterized in that the outer housing (1) has the form of an n-angled cube or square.

10. Overvoltage protection arrangement according to claim 1, characterized in that the inner wall of the outer housing (1) has a thermal radiation-reflecting coating or thermal radiation-reflecting properties.

11. Overvoltage protection arrangement according to claim 1, characterized by its use as a compact, encapsulated circuit board mountable unit, the size of the encapsulation being essentially determined and specified by the dimensions of the varistors used.

Description

(1) In the following the invention is described in more detail based on exemplary embodiments and with reference to the attached Figures.

(2) These show:

(3) FIG. 1 a basic circuit diagram of the overvoltage protection arrangement with three varistors and a gas arrester and the respective paths;

(4) FIG. 2 a perspective view of the first embodiment of the invention with removed outer housing;

(5) FIG. 3 a perspective exploded view of a first embodiment of the invention with parallel stack arrangement of varistors as well as a gas arrester, which, like the varistors, has a separate thermal disconnection device;

(6) FIG. 4 a perspective view of the first embodiment with low temperature soldered connection of the disconnection device in the L/N path in closed state;

(7) FIG. 5 an illustration in according to the one of FIG. 4, however in disconnected state 19 of the L/N path;

(8) FIG. 6 a perspective view of the first embodiment of the invention with low temperature isolating distance in the N/L path in disconnected state 18.

(9) FIG. 7 an illustration similar to the one according to FIG. 6, however in disconnected state 19 of the N/L path;

(10) FIG. 8 a perspective view of the first embodiment of the invention with thermal disconnection device for the gas arrester in closed state;

(11) FIG. 9 an illustration similar to the one according to FIG. 8, however in disconnected state 15 (arrow display);

(12) FIG. 10 a basic circuit diagram of an embodiment of the overvoltage protection arrangement with thermal disconnection device for varistors only, i.e. without thermal disconnection of the gas arrester and the wiring in the L/N, N/L and PE paths;

(13) FIG. 11 a perspective view of the second embodiment of the invention, i.e. the one having a gas arrester without thermal disconnection device;

(14) FIG. 12 a perspective exploded view of the embodiment with a gas arrester without separate thermal disconnection device;

(15) FIG. 13 an illustration in accordance with the second embodiment with closed thermal disconnection device 230 in the L/N path;

(16) FIG. 14 an illustration similar to the one according to FIG. 13, but in disconnected state 240 (arrow display) of the L/N path;

(17) FIG. 15 a perspective view of the disconnection device according to the second embodiment with closed disconnection device 230 in the N/L path and

(18) FIG. 16 an illustration similar to the one according to FIG. 15, but in disconnected state 240 of the N/L path.

(19) FIG. 1 shows a basic circuit diagram of the first embodiment of the invention with three varistors and a gas arrester, wherein in the L/N path and in the N/L path there is in each case a thermal disconnection device for the varistors and in the direction PE a thermal disconnection device for the gas arrester provided. The energetic effect of the varistors on the corresponding disconnecting devices in path L/N or N/L on the disconnecting side is shown with the symbolic dotted arrows and symbolized in an analogous manner with respect to the gas arrester in direction PE.

(20) The overvoltage protection arrangement in accordance with FIGS. 2 and 3 as well as 11 and 12 is initially based on a supporting plate 7.

(21) This supporting plate 7 consists of a plastic injection molding material. Slot-shaped openings 72 are provided in the supporting plate 7, which serve for feeding through connections 6 and 61.

(22) The corresponding feed-through connections 6 and 61 can be used for direct contacting and soldering on a printed circuit board (not shown).

(23) The overvoltage protection arrangement according to FIGS. 2; 3 and 11; 12 furthermore comprises an embodiment of a plurality of planar varistors 2; 21; 22. These varistors form a parallel stack arrangement.

(24) This parallel stack arrangement is delimited on two opposite sides by one insulating partition wall 3; 31 each, which is mountable on a supporting plate 7.

(25) Each partition wall 3; 31 has at least one opening for a varistor terminal 62, which is connected with one thermal disconnection device each.

(26) These thermal disconnection devices comprise a spring-loaded disconnecting lever 80.

(27) The respective disconnecting lever 80 is connected at its first end with the respective varistor terminal 62 by the soldered connection 18 in path L/N or path N/L 20, respectively.

(28) At its second end, the respective disconnecting lever 80 merges into one of the electrical terminals 6 (path L/N), which penetrates through the supporting plate 7.

(29) The thermal disconnection device furthermore comprises an insulating slide 4, whose free end acts on the disconnecting lever 80, wherein the slide 4 runs in recesses 81 of the respective partition wall 3.

(30) A change of position of the slide 4 can be seen by means of a viewing opening in the outer housing 1 having the form of a window 8.

(31) The slide 4 furthermore comprises two pins for guiding reception of one coil spring 5 each.

(32) The arrangement comprises at its partition-free side a gas arrester 10, which is electrically connected to the varistor stack arrangement pursuant to FIG. 1 or FIG. 10 in accordance with the second embodiment.

(33) The gas arrester 10 has a separate thermal and spring force supporting disconnection device.

(34) In this respect, the disconnection device for the gas arrester 10 comprises two torsion springs 9.

(35) As is apparent from FIGS. 2 and 3, the slide 4 engages in the close proximity of the soldered connection point between the disconnecting lever 80 and the varistor terminal 62. FIGS. 2 and 3 additionally reveal recesses 13 in the outer housing 1. The recesses are used to accommodate detent hooks 14 to form a snap-in connection. Reference sign 10 indicates the low-temperature soldered connection of the disconnection device for the gas discharge arrester and reference sign 18 indicates the corresponding low-temperature soldered connection for the disconnection device of the varistors. The torsion springs 9 according to FIG. 3 are pre-loaded and guided by the stub shafts 11 and 12.

(36) Reference sign 16 indicates the separation points electrode on the varistor side and reference sign 17 indicates the separation points electrode on the gas discharge arrester side.

(37) The illustration according to FIG. 11 und 12 comprises a comparable embodiment as illustrated in FIGS. 2 and 3, with the difference that the gas arrester 10 according to FIGS. 11 and 12 has no separate thermal disconnection device with corresponding contact bow and torsion spring 9.

(38) FIGS. 4 and 6 illustrate the thermal disconnection device for varistors in closed state and FIGS. 5 and 7 in open state, e.g. in disconnected state.

(39) FIG. 8 illustrates the state of the non-disconnected thermal disconnection device for the gas discharge arrester 10 and FIG. 9 the respective disconnected state 15.

(40) FIG. 10 shows the circuit diagram of the internal wiring in accordance with the second embodiment of the invention, wherein in this embodiment the gas discharge arrester located in PE direction has no separate disconnection device. Instead, normal soldering 210 takes place at the corresponding contact point. The arrangement of the other assemblies, in particular the thermal disconnection devices for varistors 2, corresponds to that according to the first embodiment.

(41) The non-disconnected state 230 and 230 is illustrated in FIGS. 13 and 15 and the disconnected state 240 and 240 is illustrated in FIGS. 14 and 16.

(42) The soldered connection of the gas arrester 10 according to the second embodiment with the electrode 16 of the corresponding varistor 2 is supported by a slot-shaped recess in the connecting part 17 of the gas arrester 10.

(43) The inner wall of the outer housing 1 can additionally comprise a thermal radiation-reflecting coating and may be adapted to be thermally und electrically insulating.