KR20010098775A - Device for protecting overvoltage - Google Patents

Abstract

The present invention relates to an overvoltage protection device for an electronic device comprising a plug device having at least one plug element. According to the invention, the plug device is formed to be inserted into the housing of the electronic device. In the overvoltage protection device formed such that no additional shielding treatment is required for the electronic device, a protective substrate having a discharger for inducing overvoltage is disposed in the plug element.

Description

Overvoltage Protection Devices {DEVICE FOR PROTECTING OVERVOLTAGE}

The present invention relates to an overvoltage protection device for an electronic device having a plug device comprising at least one plug element formed for securing to a housing of the electronic device.

In order to protect the electronics against high voltages, voltage fixing elements, such as varistors or zener diodes, can typically be used. Such overvoltage protection elements must be formed in the housing so that the functions of the electronic components that perform the function of the device are not impaired.

It is an object of the present invention to provide an overvoltage protection device which is formed such that no additional shielding treatment is required for the electronic device.

1 is a cross-sectional view of a control device,

2 shows a first embodiment of an interference suppressing substrate according to the present invention,

3 is a second embodiment of an interference suppression substrate according to the present invention;

4 is a third embodiment of an interference suppression substrate according to the present invention;

5 is a fourth embodiment of an interference suppression substrate according to the present invention;

6 is a capacitor surface with points without copper.

Explanation of symbols on the main parts of the drawings

1, 2: housing 3, 5: plug element

9: protective substrate 10. 15. 16: interference suppression device

13, 14: opening 17: insulation

18: conductor face 19, 20, 21, 22: conductor strip

23: substrate edge 24, 25: insulating layer

29: soldering cut lacquer 30: soldering land

34: conductor peak

According to the present invention, the above object is achieved by arranging a protective substrate having a discharger for inducing an overvoltage in a plug element.

An advantage of the present invention is that shielding is not required for components that are already high voltage induced in the outer side of the housing.

Preferably the protective substrate with plug elements forms a discharger.

In a refinement of the invention the protective substrate has a conductive structure to form a discharger. Such etched structures can be simply produced and cause spark discharges in the horizontal direction on the substrate surface.

Preferably, the conductive structure is formed on the protective substrate in the form of a conductor strip, and the area without the solder cut lacquer of the conductor strip is disposed around the opening receiving the plug element. By using conventional manufacturing methods for printed circuit boards the solder barrier lacquer area can be simply incorporated into the solder barrier mask. Here, the discharger is realized by existing components such as plug elements and conductor strips. No additional voltage fixing element is required.

The discharger is reliably realized by the formation of a region in the solder land surrounding the opening, in which an area without solder cut-off lacquer is formed.

In a refinement of the invention the conductive structure is formed as a through opening of a recess or protective substrate without solder barrier lacquer, which is arranged close to the plug pin to be protected.

To realize the vertical flame discharge, the protective substrate has two conductor strips that guide different overlapping potentials, which are guided to the substrate edges, and the strength of the insulating layer disposed between the two conductor strips does not allow the discharger to insulate both conductor strips. And to be formed at the substrate edge with the non-end end. The thickness of the insulating layer is used to determine the spacing of the dischargers and to make the production very accurate and without increasing the cost.

Fabrication can be further simplified when the substrate edge is formed by the through opening of the protective substrate. The opening may be provided wherever the reference potentials to be protected overlap, for example by simple provision of a bore.

The protective substrate preferably supports an interference suppression device for improving the electronic sensitivity of the electronic device. This integrates processing into the device plug to increase overvoltage protection and electronic compatibility.

In an embodiment the interference suppression device is a varistor.

As an alternative thereto, the interference suppression device is a capacitor which is arranged outside of the housing of the electronic device and which is electrically connected to the plug element of the plug device on one side and to the potential of the housing which is formed conductively on the other side.

An advantage of the present invention is that interference suppression is already realized at the outer surface of the electronic device and the disturbing light beam never reaches inside the housing. An interference suppression filter is created by simply inserting a plug into the housing during assembly of the electronic device. The additional processing is omitted.

Preferably the first capacitor plate of the capacitor is arranged in and / or in the plug device so that no line for the capacitor is needed.

Preferably the capacitor plate is formed of the plug element itself. The capacitor plate can be realized simply by upsetting the plug pins, for example. Thus, the manufacture of the plug is further simplified.

As an alternative to this, the first capacitor plate is arranged on the protective substrate and is formed of a conductor strip formed of a conductor surface, which conductor side is disposed next to the plug element guiding the first potential and is electrically connected to the plug element. The conductive housing for guiding the second potential of the electronic device is used as the second capacitor plate. The connection of the uninsulated plug pin and the first capacitor surface is made by positive coupling and / or non-positive coupling. Thus, a device is produced which can be used particularly suitably for ground production.

The second conductor face disposed on the protective substrate to realize the second capacitor plate is electrically connected to the housing.

An interference suppression device which can be used particularly suitably in the manufacture of the ground is that the electrical connection between the second conductor surface of the protective substrate and the housing is made by at least one fixing means for securing the protective substrate and / or plug device to the housing. Here, the housing potential is realized at at least one point by means of a screw-, rivet- or press connection present.

In an embodiment of the invention an insulation is disposed between the second conductor surface formed on the surface of the protective substrate and the outer surface of the housing. As an alternative thereto, the conductor face disposed on the surface of the protective substrate is provided directly on the housing.

In a refinement of the invention, the conductor surface surrounding the plug element is arranged on the protective substrate in such a way that the conductor surface can be arranged on and in contact with the side facing the housing of the plug device. Thus, a plug which is commonly used may have a protective substrate according to the invention. Here, a first capacitor plater, preferably electrically insulated from each other, is provided for each plug element of the plug device.

The present invention has numerous embodiments. One of the above embodiments is explained in more detail by the figure shown in the drawings.

Identical features are denoted by the same reference numerals.

1 shows an electrical device typically used in a motor vehicle. Here, the control device of a motor vehicle having a signal processing electronic device which is very prone to failure at high frequencies in a known manner can be dealt with. However, it can be appreciated that the electronic device is a sensor device having a signal processing circuit and / or a signal evaluation circuit disposed on one or more printed circuit boards in addition to the inherent sensor.

The electronic device has a cup-shaped housing part 1 made of aluminum, which is closed by a cover 2. The cup-shaped housing part 1 has a plug body 3, which is fixed to the outside of the housing 1 by screws or rivets 4. The plug pin 5 of the plug body 3 protrudes into the plug body 3 and the interior of the housing 6. The plug 3 connects the circuit of the device to another electronic device in the motor vehicle by the plug pin 5.

At least one printed circuit board 7 supporting the elements 8 constituting the electronic circuit is disposed in the housing 6. A plug pin 5 protruding into the housing interior 6 is electrically connected to an element 8 disposed on the printed circuit board 7 for supplying signals and power.

Between the plug 3 and the outer surface of the housing part 1, an interference suppression substrate 9 fixed to the housing part 1 together with the plug 3 is inserted.

Different embodiments of the interference suppressing substrate 9 are described in more detail in FIGS. 2 to 5.

2 shows an interference suppression substrate 9 having an opening 13 for a plug pin 5. In addition to the opening 13, each plug pin 5 is provided with a distributed capacitor 10, which is connected to the capacitor 10 by means of wiring arranged on the substrate 9. Is connected to the plug pin potential, on the other hand to the potential of the housing 1. Here, the housing potential is typically at ground.

The prefabricated substrate 9 is moved over the plug pin 5, and the rotating plug seal 12 surrounds and simultaneously seals the edge of the substrate 9. The substrate 9 is fixed to the outer surface of the housing part 1 by screws 4 inserted into the opening 11 of the substrate 9 and into the opening 14 of the plug body 3. This fixing is here made such that the seal 12 rests on the housing part 1. The screw 4 electrically connects the capacitor 10 to the housing potential at the same time.

Another embodiment in which the capacitance in the substrate 9 is formed to be integrated is shown in FIG. 3. The substrate 9 has a conductor layer 15 formed and structured as a film printed circuit board. The structure corresponds to individual capacitor surfaces 16 insulated from one another. Here, for each plug pin 5 a capacitor surface 16 is provided which surrounds the opening 13 of the individual plug pin 5. The openings 13 are metalized, and the interface of each capacitor surface 16 is connected to the metalized openings 13, thereby creating an electrical connection. After insertion of the plug pin 5 the capacitor surface 16 is at the plug potential. In this embodiment, the contact press procedure is particularly preferably provided as an electrical connection mechanism.

The filter plate 9 has an additional conductor layer 18 on the surface facing the housing, which is placed on the housing 1 immediately after assembly of the plug 3. Thus, the conductor layer 18 receives a housing potential. Such an unstructured conductor surface 18 is preferably formed as a conductive adhesive, so that the interference suppressing substrate 9 can be fixed to the housing.

As an alternative thereto, the interference suppressing substrate 9 with the capacitor 16 insulated from the housing part 1 by the structured conductor layer 18 is formed by the second capacitor plate 18 of the housing 1 itself. If so, it can be assembled without the conductive surface 18.

By this design, each plug pin 5 itself acts as a capacitor plate and forms an interference suppression capacitor with the housing part 1 connected to ground.

Additional embodiments are shown in FIG. 4. According to this embodiment, the substrate 9 has four copper layers 19, 20, 21, 22. Each copper layer 19, 22 is disposed on one of both outer faces of the substrate 9. Inside the substrate 9 two additional copper layers 20, 21 are arranged, insulated from each other, the copper layers 20, 21 having a capacitor surface 16 as described by FIG. 3. ).

The two outer copper layers 19, 22 are connected to the housing potential by the fastening member 4 and are electrically insulated with respect to the potential for guiding the plug pin 5. The capacitor surface 16 is electrically connected to the plug pin 5 in the manner described. Thus, a capacitor surface pair is formed for each plug pin 2. If more capacitor surface pairs are needed, the copper layers 20, 21 forming the structured capacitor surface 16 and the unstructured copper layers 19, 22 forming the entire surface overlying the housing potential are simply replaced. Can be achieved.

In addition to what has been described above, the capacitor surface 16 is formed of a stamping or Kapton film embedded into an insulating material. It can be seen that a seal was simultaneously provided for each material or material combination used to coat the capacitor plate.

The capacitor surface according to the invention forms a capacitor in an area of less than 50 pF with respect to the outer housing.

In order to realize overvoltage protection, the non-insulated ends of the copper layers 19, 20, 21, 22 are guided to the edge 23 of the substrate 9. As an alternative to this, the copper layers 19, 20, 21, 22 end up uninsulated in the openings 14 of the substrate 9, which can be produced, for example, by providing bores.

The copper free point 32 generated during substrate fabrication produces a conductor peak 34 that promotes spark discharge after provision of the bore 33 (FIG. 6).

An insulating layer 25 is disposed between the copper layers 19 and 20, and an insulating layer 24 is disposed between the copper layers 21 and 22. The copper layers 21, 20 are separated by a third insulating layer 26, which has a thickness that is several times greater than the individual insulating layers 24 or 25 because of stability. This is because the third insulating layer 26 is used as a support layer. Since the air gap between the copper layers 19 and 20 or 21 and 22 is very small due to the thickness of the insulating layers 24 and 25, spark discharge between the copper layers occurs at the time of overvoltage.

A soldering blocking lacquer structure 29 is added on the surface of the copper layers 19, 29, which soldering lacquer structure 29 is provided in the opening 13 and the opening 13 for receiving the plug element 5. Cover the conductor strips to be connected.

The solder break lacquer structure 29 is divided at a previously provided point so that the copper layers 19 and 22 are freely placed at this point. Thus, additional conductive and nonconductive bores 27 and 28 form a horizontal flame discharger at the surface of the substrate 9.

5 also shows the possibility that the solder land 30 surrounding the opening 13 can be narrowed in order to enable spark discharge.

To this end, a soldering cut lacquer structure 29 is provided by the soldering blocking mask, and the narrow portion 31 for freely laying the copper layer 19 or 22 underlying it in the region of the soldering land 30 in the soldering blocking lacquer. This is provided at equal intervals. In this case three narrow portions 31 are provided at intervals of 90 ° C. The narrow part 31 is shown enlarged. By placing the narrow portion 31 and the plug element 3 close together, a possible discharge point for spark discharge is produced.

On the back side (bottom) of the substrate 9, solder lands 30 are formed conical in a conventional manner.

By the present invention, overvoltage protection is provided which is configured so that there is no additional shielding treatment for the electronic device.

Claims (21)

An overvoltage protection device for an electronic device, comprising: a plug device having at least one plug element formed to be secured to a housing of the electronic device; A protective substrate (9) is arranged on the plug element (3), wherein the protective substrate (9) has a discharger for inducing an overvoltage. The method of claim 1, An overvoltage protection device characterized in that the protective substrate (9) having the plug element (3) forms a discharger. The method of claim 2, The protective substrate (9) is characterized in that it has a conductive structure (19, 22) forming a discharger. The method of claim 3, wherein The conductive structure provided on the protective substrate 9 is formed in the form of a conductor strip, and the zones 27, 28 and 31 without solder barrier lacquer of the conductor strip are provided with openings for receiving the plug element 5. Overvoltage protection device, characterized in that disposed in the periphery. The method of claim 4, wherein An area (31) free of said solder break lacquer is formed in a solder land (30) surrounding said opening (13) of said solder break lacquer (29). The method of claim 3, wherein The conductive structure is characterized in that it is formed as a through opening (27, 28) of a recess and / or protective substrate (9) without a soldering blocking lacquer. The method of claim 6, The overvoltage protection device, characterized in that the recess and / or opening (27, 28) without the solder break lacquer is arranged near the plug pin (5) to be protected. The method of claim 1, The protective substrate 9 has at least two overlapping conductor strips 19, 20; 21, 22 leading to different potentials, which are guided to the substrate edge 23, the both conductor strips 19, 20; 21. , The strength of the insulating layers 24, 25 disposed between them is chosen such that a discharger is formed at the substrate edge 23 at the non-insulated ends of the both conductor strips 19, 20; 21, 22. Overvoltage protection device. The method of claim 8, The shape of the conductor strip (19, 20, 21, 22) guided to the substrate edge (23) is selected such that a conductor peak (34) is formed at the substrate edge (23). The method according to claim 8 or 9, The substrate edge (23) is characterized in that it is formed by at least one through opening (14) of the protective substrate (9). The method of claim 1, The protective substrate (9) is characterized in that it supports an interference suppression device (10; 15, 16) for improving the electromagnetic sensitivity of the electronic device (1). The method of claim 10, And the interference suppression device (10) is a varistor. The method of claim 10, The interference suppressing device is a capacitor 10, which is disposed outside the housings 1 and 2 of the electronic device 1, and on one side of the plug device 3 of the plug device 3. 5), and on the other side, to an electric potential of the conductive housing (1, 2). The method of claim 13, An overvoltage protection device, characterized in that the first capacitor plate (16) of the capacitor (10) is arranged in the plug device (3) or in the plug device (3). The method of claim 14, Overvoltage protection device, characterized in that the first capacitor plate (16) is formed by the plug element (5) itself. The method of claim 14, The first capacitor plate 16 is disposed on the protective substrate 9 and formed of one of the conductor strips 15 formed as a conductor face, the conductor strip 15 being arranged next to the plug element 5. An overvoltage protection device, characterized in that a conductive housing (1) electrically connected to the plug element (5) and connected to the ground of the electronic device is used as a second capacitor plate. The method of claim 16, An overvoltage, characterized in that the second conductor surface 18 having the housings 1, 2, disposed on the protective substrate 9 and electrically connected to the housings 1, 2, forms a second capacitor surface. Protection device. The method of claim 17, At least one electrical connection between the second conductor surface 15 of the protective substrate 9 and the housings 1, 2 secures the protective substrate 9 and / or the plug device 3 to the housings 1, 2. An overvoltage protection device, characterized in that made by the fixing means (4) of the. The method of claim 17, An overvoltage protection device, characterized in that an insulating portion (17) is arranged between the second conductor surface (18) formed on the surface of the protective substrate and the outer surface of the housing (1, 2). The method of claim 17, The conductor surface 16 surrounding the plug element 5 can be arranged on the side facing the housing 1 of the plug device 3 so that the conductor surface 16 can be contacted with the protective substrate 9. Overvoltage protection device, characterized in that disposed above. The method of claim 6 or 8, An overvoltage protection device, characterized in that for each plug element (5) is provided a first capacitor plate (16) electrically insulated from one another.