EP2452401B1 - Grounding device for a protective contact plug and protective contact plug - Google Patents

Description

The present invention relates to a grounding device for a grounded plug and a grounded plug. In particular, the present invention relates to a safety plug as described in DIN 49440/441.

A safety plug, as is common in many European countries, has two round contact pins 4.8 mm in diameter, 19 mm in length and 19 mm spacing for outer conductor and neutral conductor. A third pole, the protective contact, is intended to dissipate dangerous voltages d. H. ground as soon as the electrical circuit is closed by the other two poles, the outer conductor and the neutral conductor. Therefore, the connection with the protective contact should be made first, so be anticipatory. In the case of the earthing contact plug, this is ensured via contact surfaces on the plug side and the associated contact springs in the earthing contact socket.

To connect to the earthing contact plug, a three-core cable is used, which contains an outer conductor, a neutral conductor and a grounded protective conductor. Electrically conductive housing materials must be connected to the protective conductor.

As a grounding device, the protective contact in the safety plug is usually designed as a bent brass sheet. In the course of rising raw material prices, it is of interest to keep the consumption of expensive, electrically conductive metals or alloys, especially brass, as low as possible in the earthing device for a safety plug.

From the DE 20 2007 002 268 U1 , which corresponds to the preamble of claim 1, a grounding plate of a earthing contact plug is known, which has a base portion and two substantially perpendicular thereto extending leg portions. Each leg portion has an upper contact portion that extends to a mounting portion of the leg portion, and has a lower contact portion that extends slightly angled down from the upper contact portion. The upper contact area and the lower contact area have different length dimensions. A connection region for the mechanical connection to a frame of the earthing contact plug is bow-shaped.

The document EP 1 936 744 A2 discloses a contact element for a ground potential connection with a mounting rail. From a central region of the contact element, a spring tongue is bent out, and from an end region of the contact element integrally extending two spring angle. The spring tongue and the spring angle are provided for connection to the mounting rail.

From the DE 73 0318 U is a grounding post with a base part and from this substantially perpendicular extending legs known. Each leg has a contact area connected to the base part with laterally arranged teeth and a contact area with smooth side surfaces arranged away from the base part.

The document DE 69 16 076 U discloses a grounded plug with a grounding post having a base portion and a leg extending perpendicular thereto. The leg has at a location remote from the base part on a bending area to form a chamfer.

It is an object of the present invention to provide a grounding device for a safety plug and a safety plug, which are inexpensive to produce with reduced material costs.

This object is achieved according to the invention by a grounding device having the features of claim 1.

Because the contact regions have a different length and / or width and preferably the second contact region is narrower than the first contact region, it is possible to save electrically, conductive material, in particular brass, in a contact region, preferably in the second contact region. This reduces the material costs in the production of the grounding device.

At one end of the first contact region, a connection region is provided, which can be brought into mechanical engagement with a plug bridge of the protective contact plug. As a result, a reliable fixation of the grounding device is achieved in the safety plug when the grounding device is installed in the safety plug.

In particular, it is advantageous if the second contact region is arranged between the two webs of the connecting region. By the two webs a particularly reliable, mechanical connection of the connecting portion is achieved with the plug bridge of a earthing contact plug when the grounding device is installed in the safety plug.

According to a preferred embodiment, the second contact region is formed as a contact extension, which protrudes at one end of the first contact region. This contact extension increases the effective contact area of the leg portion, d. H. the contact surface with the grounding device of the earthing contact plug when plugged into a grounded socket the grounding device of the socket, usually a contact spring, contacted.

In particular, it is advantageous if the connection region for the mechanical connection with the connector bridge is bendable.

According to a further preferred embodiment, the second contact region is formed at the end of the first contact region.

Preferably, an outer distance of the two webs is equal to the width of the first contact region.

According to a further preferred embodiment, an inner distance of the two webs is greater than the width of the second contact region. On the one hand, material is thus saved. If the second contact region is preferably spaced apart from both webs, on the other hand it is prevented that the two webs interfere with the second web

Hook the contact area when the connection area for fixing the earthing device is bent over on the plug bridge.

Preferably, the connection region is formed substantially U-shaped.

According to a further preferred embodiment, a substantially U-shaped recess is formed between the connection region and the second contact region. As a result, further material is saved and it is prevented that the connection area hooked to the second contact area when the connection area is bent during assembly of the grounding device in the grounding plug.

According to a further preferred embodiment, the connecting region has at least one end-side recess, which is arranged at the end of the leg portion. As a result, further electrically conductive material is saved in the production of the grounding device.

Preferably, a substantially vertical leg portion, each having a first and a second contact region is arranged at both ends of the base portion. If the earthing device is installed in a safety plug, the earthing contact plug can be plugged into the earthing contact socket in two positions, which are rotated by 180 °, with grounding in both positions.

Preferably, the base portion and the two leg portions are formed as a component.

Further preferred embodiments of the grounding device are set forth in further dependent claims.

The above object is further achieved according to the invention by a safety plug with a grounding device according to at least one of the preceding embodiments.

The safety plug preferably has a plug bridge which has at least one projection with which the connection region of the earthing device is engaged.

In particular, it is advantageous if the connection region of the grounding device surrounds the projection of the plug bridge. As a result, a particularly reliable, mechanical connection between the grounding device and the connector bridge is achieved.

Preferably, the second contact region of the grounding device covers an outer surface of the projection of the connector bridge. By virtue of the projection, a rear side of the second contact region is mechanically stabilized, whereby the second contact region is prevented from bending during assembly of the grounding spring to the plastic body, which can lead to overmoulding or poor parts during encapsulation with PVC.

Further preferred embodiments of the earthing contact plug are set forth in further dependent claims.

Fig. 1

eine Seitenansicht einer fertig gebogenen Erdungsvorrichtung mit zwei Schenkelabschnitten (schematisch),

Fig. 2

eine Draufsicht auf einen Schenkelabschnitt einer Erdungsvorrichtung im ungebogenen Zustand (schematisch),

Fig. 3a

eine Draufsicht auf ein Schenkelabschnitt nach Fig. 2 in gebogenem Zustand (schematisch), und

Fig. 3b

eine perspektivische Darstellung eines Bereichs eines Schutzkontaktsteckers ohne PVC - Umspritzung, mit einer Erdungsvorrichtung, die mit einer Steckerbrücke des Schutzkontaktsteckers verbunden ist.

The present invention will be explained in more detail below with reference to preferred embodiments in conjunction with the accompanying figures. In these show:

Fig. 1

a side view of a finished bent grounding device with two leg sections (schematically),

Fig. 2

a plan view of a leg portion of a grounding device in the unbent state (schematically),

Fig. 3a

a plan view of a leg portion after Fig. 2 in a bent state (schematic), and

Fig. 3b

a perspective view of a portion of a safety plug without PVC - encapsulation, with a grounding device which is connected to a plug bridge of the earthing contact plug.

In Fig.1 is a side view of a finished bent grounding device 1 with two leg portions 3 shown. In Fig. 2 is a plan view of a leg portion 3 of a grounding device 1, for example, the grounding device 1 from Fig. 1 , shown in the unbent state. Fig. 3 shows a perspective view of a portion of a safety plug 20 without PVC encapsulation with a grounding device 1, for example, a grounding device 1 from Fig. 1 which is connected to a plug bridge 21 of the earthing contact plug 20.

In the Fig. 1 Grounding device 1 shown has a base portion 2 (shown cut here) and two leg portions 3. Preferably, the grounding device 1 is made of an electrically conductive sheet-metal strip, for example made of brass sheet, in one piece, for example punched out.

In order to electrically conductively connect a protective conductor to the grounding device 1, preferably the base section 2 has a crimping socket or threaded bushing (not shown) for making electrical contact with the protective conductor by clamping or screwing in a screw.

The leg portions 3 are arranged at both ends of the base portion 2 and each extend substantially perpendicular to the base portion 2, so that the leg portions 3 are arranged opposite to each other. Although the in Fig. 1 1 shows two leg sections 3, it is also possible for the grounding device 1 to have only one base section 2 and a leg section 3 arranged substantially perpendicular thereto.

The term "substantially" is used in this context, since the grounding device 1 is preferably made of an electrically conductive sheet-metal strip, wherein the leg or sections 3 are bent with respect to the base portion 2. By folding, it is possible that the base portion 2 and the respective leg portion 3 include an angle which does not correspond exactly to 90 °, but is slightly larger or slightly smaller (for example, ± 5 °) than the 90 ° angle.

This makes it possible to set a bias of the leg portions 3 in the attachment to the connector bridge 21. Preferably, the grounding device 1 is therefore designed as a grounding spring.

The leg portions 3 extend in the longitudinal direction L of the earthing device 1. The longitudinal direction L extends in the direction of a longitudinal axis of the earthing contact plug 20, in which the earthing device 1 is mounted, that is, in the direction of the longitudinal direction. H. in the direction of the contact pins (not shown) of the protective contact plug 20th

Usually, the base portion 2 in the grounding device 1 can be seen from the outside when looking at the safety plug 20 in the longitudinal direction L. The lower Areas of the leg portions 3 can be seen on opposite sides of the connector bridge 21 of the earthing contact plug 20.

Preferably, the two leg portions 3 in Fig. 1 by mirroring on a surface in which the longitudinal axis of the protective contact plug 20 extends, mapped to each other. However, it is also possible that the two leg portions 3 are formed by a 180 ° rotation about this longitudinal axis from each other.

The in Fig. 2 shown leg portion 3 has a first contact region 4 and an adjoining second contact region 5. The first contact area 4 begins, based on Fig. 2 in a lower region of the leg portion 3, ie in the region in which the leg portion 3 is preferably integrally connected to one end of the base portion 2. The first contact region 4 extends from the lower region to an upper region of the leg section 3, wherein the entire first contact region 4 preferably has a constant width B _S and an uninterrupted, substantially planar contact surface.

Related to Fig. 2 In the upper region of the leg section 3, the second contact region 5 adjoins the first contact region 4. The second contact region 5 is formed as a contact extension, which projects at the upper end of the first contact region 4. Preferably, the first contact region 4 and the second contact region 5 are formed from the same electrically conductive material, and in particular formed as a component.

The second contact region 5 has a width B _K , which is smaller than the width B _{S of} the first contact region 4. Thus, the first contact region 4 is formed wider than the second contact region 5.

The second contact region 5 also preferably has a continuous, preferably flat, contact surface, which in particular is continuous with the contact surface of the first contact region 4. Both contact areas 4, 5 thus form an uninterrupted, effective contact surface 10, which preferably has a total length L _K of at least 14.5 mm, preferably at least 16.5 mm and most preferably at least 17.5 mm.

The effective contact surface 10, which is composed of the contact surface with the length L _{K of} the first contact region 4 and the contact surface of the second contact region 5, is used along its entire length L _K for mechanical and electrical contacting of another grounding device, in particular a grounding spring, a safety socket when the safety plug 20 is inserted into the socket outlet or pulled out of it.

At the upper end of the first contact region 4 is in Fig. 2 Furthermore, a connecting portion 6 is provided which can be brought into mechanical engagement with the plug bridge 21 of the earthing contact plug 20, as shown in FIG Fig. 3 is shown. For this purpose, the connection region 6 is preferably bendable, ie the electrically conductive material of the grounding device 1 is plastically deformable at least in this area. Also, the connecting portion 6 of the leg portion 3 is preferably formed integrally with the remaining leg portion 3.

While in Fig. 1 the two opposite connecting portions 6 are already bent, is the in Fig. 2 shown connection area 6 is still flat with the first and second contact area 4, 5.

In the in Fig. 2 illustrated embodiment, the connecting portion 6 has two opposing webs 7, whose inner edges are spaced from each other by an inner distance A _i . The outer edges of the two webs 7 are spaced from each other by an outer distance A _ä . Preferably, the outer distance A _ä 7 corresponds to the two webs of the width B _S of the first contact region. 4

The in Fig. 2 shown connecting portion 6 is formed bow-shaped, wherein an end-side portion connects the two webs 7 together. In particular, the connection region 6 is substantially U-shaped. The end section is with reference to Fig. 2 arranged at the upper end of the leg portion 3, ie at the distal end of the leg portion 3 relative to the base portion. 2

The end-side section has one or more end-side recesses 9 in order to save further material during the production of the grounding device 1. Preferably, the end-side recess 9 is arcuate. But there are others too Shapes, for example triangular or square end-side recesses 9 possible.

In Fig. 2 the second contact region 5 is arranged as a contact extension between the two webs 7. The second contact region 5 preferably has a width B _K of at least 3.5 mm.

The inner distance A _{i of} the two webs 7 is greater than the width B _{K of} the second contact region 5, so that there is a recess 8 between the respective web 7 and the nearest edge of the second contact region 5 on one or both sides. This makes it possible to save further material in the manufacture of the grounding device 1. Furthermore, it is achieved by recesses 8 on both sides of the second contact region 5 that the webs 7 of the connecting region 6 and the lateral edges of the second contact region 5 do not get caught when the connecting region 6, as in FIG Fig. 3a and Fig. 3b shown, is bent over.

Particularly preferably, the end-side section of the connection region 6 is spaced from the second contact region 5 in order to save further material in the production of the grounding device 1 and to prevent the connection region 6 from catching on the second contact region 5 when the connection region 6 is bent over. Thus, it is particularly advantageous if the recess 8 between the connecting region 6 and the second contact region 5 is formed substantially U-shaped.

In the unbent state, ie when the connection area 6 is not as in Fig. 3 shown bent, the leg portion 3 preferably has a total length L _S of at least 19.5 mm. The recess 8 is a perforated surface which is defined by the width B _{K of} the second contact region 5, the inner distance A _i between the two webs 7 and the length L _{A of} the recess 8 in the longitudinal direction L.

The first contact region 4 has the length L _I. The length of the second contact region 5 is L _K -L _I.

In Fig. 3b the grounding device 1 is shown in a mounting situation, wherein Fig. 3a a schematic plan view of the already developed, but not yet mounted grounding device shows. The illustrated safety plug 20 is in particular a safety plug according to DIN 49440/441, but without the surrounding, electrically insulating housing is shown. The housing, not shown, for example, be screwed or clipped, or can also be made by encapsulation of the connector bridge 21 with an electrically insulating plastic, such as PVC.

The plug bridge 21 of the earthing contact plug 20 has at least one projection 22 with which the connecting region 6 of the grounding device 1 is engaged. Preferably, the plug bridge 21 has two projections 22 which are opposite in the radial direction of the protective contact plug 20, of which only one is shown here. With these two projections 22, the in Fig. 1 shown grounding device 1 engaged.

When the connecting portion 6 of the earthing device 1 bow-shaped, in particular as in Fig. 2 shown U-shaped, the connecting portion 6 surrounds the projection 22 of the connector bridge 21, as shown in FIG Fig. 3b is shown. If the connecting region 6 is bent over in order to bring the grounding device 1 into engagement with the plug bridge 21, it is advantageous if the connecting region 6 and the two contact regions 4, 5 of the leg segment 3 are at an angle of less than 90 °, for example 85 ° or 80 ° , lock in. As a result, the mountability of the grounding device 1 is improved, and it is possible to bias the grounding device 1 during assembly.

It is particularly advantageous if the connection region 6 of the grounding device 1 is bent below an upper edge 11 of the second contact region 5. For this purpose, for example, the webs 7 at half the length or, starting from the end of the first contact region 4, bent over to a third of their length. For example, after mounting the grounding device 1 on the plug bridge 21, the unbent portion of the leg portion 3 has a total length of 17.5 mm, while referring to FIG Fig. 3 the uppermost 2.5 mm of the leg portion 3 or of the connecting region 6 are bent so that this region encloses an angle of less than 90 ° with the first-mentioned region of the leg portion 3.

In Fig. 3b The second contact region 5 of the grounding device 1 completely covers an outer surface of the protrusion 22 of the connector bridge 21. Thus, the protrusion 22 supports the rear side of the second contact portion 5, thereby preventing the second contact portion 5 in the mounting of the contact spring toward the center connector bridge 21 can be bent. This is advantageous if the plug-in bridge 21 is encapsulated with an electrically insulating plastic, for example PVC, since over-molding or burrs are prevented by the flush termination.

The embodiments explained above relate to a grounding device 1 for a grounding plug 20 having at least one base section 2 and at least one leg section 3, which is arranged substantially perpendicular to the base section 2, wherein the leg section 3 has a first and a second contact region 4, 5 for electrically contacting a Grounding device of a safety socket has, and the first contact region 4 is wider than the second contact region 5 is formed.

Likewise, the above-described embodiments relate to a safety plug 20 with a grounding device 1 according to at least one of the preceding embodiments.

Claims (14)

1. Grounding device for a protective contact plug (20) with at least one base section (2) and at least one leg section (3) which is arranged substantially perpendicular to the base section (2), wherein the leg section (3) comprises a first contact area (4) and a second contact area (5) for electrically contacting a grounding device of a protective contact receptacle, wherein a length (L_l; L_K-L_l) and/or a width (B_K; B_S) of the contact areas (4, 5) are different, and wherein in connection with an end of the first contact area (4) a connection area (6) is provided which can be engaged with a plug insert (21) of the protective contact plug (20) for mechanical connection and which comprises two webs (7) and wherein the connection area (6) is connected with the end of the first contact area by said two webs (7), characterized in that the second contact area (5) is disposed between said two webs (7).
2. Grounding device according to claim 1, characterized in that the first contact area (4) is wider than the second contact area (5).
3. Grounding device according to one of claims 1 or 2, characterized in that the second contact area (5) is embodied as a contact extension which projects from the first contact area (4), preferably extends in the longitudinal direction from one end of the first contact area (4).
4. Grounding device according to at least one of claims 1 to 3, characterized in that the connection area (6) can be bent over for mechanical connection with the plug insert (21).
5. Grounding device according to one of claims 1 to 4, characterized in that the second contact area (5) is embodied at the end of the first contact area (4).
6. Grounding device according to at least one of the claims 1 to 5, characterized in that an outer distance (A_ä) of the two webs (7) equals the width (Bs) of the first contact area (4), and/or an inner distance (A_i) of the two webs (7) is wider than the width (B_K) of the second contact area (5).
7. Grounding device according to at least one of claims 1 to 6, characterized in that the connection area (6) has a substantially U-shaped design, and/or a substantially U-shaped recess (8) is formed between the connection area (6) and the second contact area (5).
8. Grounding device according to at least one of claims 1 to 7, characterized in that the connection area (6) comprises at least one recess (9) at the end side which is arranged at the end of the leg section (3), in particular the recess (9) on the end side has a substantially bow-like design.
9. Grounding device according to at least one of claims 1 to 8, characterized in that the first and the second contact area (4, 5) comprise a contact surface (10) having a total length (L_K) of at least 14,5 mm, preferably at least 16,5 mm, in particular preferably at least 17,5 mm, in particular the second contact area (5) has a width (B_K) of at least 3,5 mm.
10. Grounding device according to at least one of claims 1 to 9, characterized in that at both ends of the base section (2), one substantially perpendicular leg section (3) each is arranged with a first and a second contact area (4, 5) each, wherein in particular the base section (2) and the two leg sections (3) are embodied as one component and, preferably, the grounding device consists of a thin strip, preferably a cutting and bending part of brass.
11. Protective contact plug with a grounding device (1) according to at least one of claims 1 to 10.
12. Protective contact plug according to claim 11, with a plug insert (21) which comprises at least one projection (22) with which the connection area (6) of the grounding device (1) is engaged wherein, in particular, the connection area (6) of the grounding device (1) grips around the projection (22) of the plug insert (21), preferably the connection area (6) and the two contact areas (4, 5) include an angle of less than 90°.
13. Protective contact plug according to claim 12, characterized in that the connection area (6) of the grounding device (1) is bent over underneath an upper edge (11) of the second contact area (5), in particular the second contact area (5) of the grounding device (1) covers an outer surface of the projection (22) of the plug insert (21).
14. Protective contact plug according to at least one of claims 12 or 13, characterized in that an upper edge (11) of the second contact area (5) of the grounding device (1) is flush with an upper edge (23) of the projection (22) of the plug insert (21).

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