DE102013113215B4 - NH-bar - Google Patents

Abstract

The invention relates to an NH bar (1) with a housing (2) having a housing opening (2a) and a cover (3) which is pivotably mounted on the housing (2) and by means of which the housing opening (2a) can be locked, with the housing ( 2) an access contact (6) and an outgoing contact (7) are arranged. An NH fuse (5) is attached to the cover (3), the NH fuse (5) only making contact with the access contact (6) and the output contact (7) when the cover (3) is closed. A mechanical protective device is provided which can be actuated automatically when the cover (3) is opened and by means of which access to the access contact (6) and output contact (7) is blocked when the cover (3) is open.

Description

The invention relates to a NH bar.

Such NH strips are used in the field of power supply for load distribution and selective protection of power lines in different applications, especially in distribution systems for the distribution and supply of electrical power to house connections. In particular, such NH bars can be used in underfloor systems.

Such underfloor systems have been increasingly used for some time in the field of public energy supply and telecommunications. For visual and aesthetic reasons, above-ground distribution boxes with electrical distributors, including electrical connection means such as NH strips for house connections, in cities and towns increasingly also buried underground. The underfloor systems installed for this purpose generally comprise a distributor which is placed in a shaft, wherein the shaft can be closed at ground level with a manhole cover.

NH strips generally have a structure such that their components are integrated in a housing which has on a top side a housing opening which can be closed with a lid. The lid is hinged to the housing, so that it is pivotable for closing the housing on the housing opening down and can be pivoted to open the NH bar upwards.

In the interior of the housing, an access contact and an outgoing contact are arranged. On the access contact incoming lines are connected. At the outgoing contact, lines going out from the NH strip are connected.

An NH fuse is attached to the inside of the lid of the NH bar. If the lid of the NH bar is closed, the NH fuse is electrically contacted with the access contact and the outgoing contact.

If the lid is swiveled up to open the NH bar, the NH fuse is also lifted and the access contact and the outgoing contact are exposed and can be accessed unhindered through the housing opening.

In known NH bars typically several electrical protection measures are provided. For example, NH strips are for the most part completely encapsulated, in particular provided with plastic sheathings. Furthermore, the access contact and the outgoing contact are carried out touch-safe on their own.

Nevertheless, hazardous situations may arise when the housing opening of the NH bar is open, which is due to the exposed contacts, that is to say the access contact and the outgoing contact. Namely, if an operator opens the NH bar and thereby drops an elongate object such as a wrench or a ballpoint pen, this object, when he falls on the access and exit contact simultaneously, a conductive connection between the contacts arise, creating a dangerous short circuit is effected.

An NH bar according to the preamble of claim 1 is known from DE 890 380 B known. There, a finger-safe circuit breaker is described, the fixed contacts are mounted behind an insulating wall on a common plate and sit his fuses on an insulating switching flap. The plane of the insulating wall has a passage opening for the directly with their contact lugs in the closed position bridging the fixed fuse. In the off position, the fixed contacts are covered against hand contact from the front side by an insulating part.

The DE 17 79 892 U relates to a circuit breaker or disconnector with operable by a switch cover fuse links or separating knives. Within the switch housing, in addition to the switching connections for the power line, an additional line connection or switching connection with separate line connections, for example, for the neutral conductor, arranged. The switching connections are covered with a contact protection wall.

The DE 1 246 848 B relates to a fuse isolator or fuse load disconnector with a fixed, slotted cover plate for the mating contacts of NH fuses and an adjustable by the actuator of the switch and spring force cover, which is housed in the on state of the switch between the fuses and the bottom of the switch and when turned off in a protective layer passes, in which the mating contact pieces are covered against lateral contact. The adjustable cover consists of two insulating walls, which lie in the closed position in the space between the sockets of the fixed contact pieces. The insulating walls can be transferred in the off position by moving or pivoting in a position perpendicular to the stationary cover plate and near the fixed contact pieces of each connection side.

The invention has for its object to increase the lowest possible design effort the reliability of a NH bar of the type mentioned.

To solve this problem, the features of claim 1 are provided. Advantageous embodiments and expedient developments of the invention are described in the subclaims.

The invention relates to a NH strip with a housing opening having a housing and a pivotally mounted on the housing cover, by means of which the housing opening is lockable, wherein in the housing an access contact and outgoing contact are arranged. An NH fuse is attached to the lid, whereby the NH fuse is only contacted with the access contact and the outgoing contact if the lid is closed. A by the opening of the cover automatically actuated mechanical protection device is provided, which is formed by a flexible surface element, which is up on a shaft and unrolled. By means of the protective cover, the access to either the access contact or the outgoing contact is blocked when the cover is open.

The basic idea of the invention is that reliable protection against a short circuit when the lid of the NH strip is opened is achieved solely by a mechanical blocking of one of the contacts of the NH strip, that is to say either the access contact or the outgoing contact. Since the access to one of the contacts is blocked by the mechanical protection device when the lid of the NH bar is open, it can indeed be electrically connected to the still free contact in the event of accidental dropping in of an elongate metallic object, but not with the one through the Guard protected contact.

It is essential that the mechanical protection device is actuated automatically by the opening of the lid, that is, when the lid is opened, the protective device automatically locks the respective contact. The protection device thus has a high level of error safety, since this function is ensured without any intervention by operators.

Furthermore, it is advantageous that the protective device always and reliably fulfills its function of protecting the contacts of the NH bar with the lid open, since the protective device is actuated by the opening process of the lid itself and not by operations to be monitored separately.

Another advantage is the modular design of the protective device according to the invention. The protective device can thus be easily retrofitted as a kit to existing NH bars. In this case, the protective device can be used for different types of NH strips, wherein in particular the term NH strip also includes so-called NH separator.

In principle, it is possible to provide inflatable units as protection devices or elements which are folded into the areas of terminal slots of the access contact or outgoing contact.

According to a particularly advantageous embodiment of the invention, the mechanical protection device is designed as a protective cover, which covers the access contact and outgoing contact with the lid open.

The protective cover is automatically extended when opening the lid from a closed position.

Likewise, the protective cover moves automatically when closing the lid in the closed position.

This is a structurally particularly simple and yet very failsafe and robust variant of the protection device. The protection of the access contact or outgoing contact is simply effected by coating the protective cover, wherein the process of coating with the opening of the lid can be carried out very safely and reproducibly.

Another advantage of the invention is that the protective device forms a purely mechanical element, which on the one hand is inexpensive to produce and on the other hand has a robust and fail-safe construction.

According to the invention, the protective cover is formed by a flexible surface element which can be wound up and down on a shaft.

The flexible surface element is formed by a net, a film or a textile surface.

The shaft is mounted on the bottom of the housing.

The shaft has a roll-up mechanism for the flexible surface element.

At the upper, free edge of the flexible sheet member bands are attached, which are connected to the lid.

The winding and unwinding of the flexible surface element on the shaft can also be about many Opening and closing cycles are performed wear-free and reproducible.

At the flexible surface element are up to a certain tear resistance no special material requirements.

By attaching the shaft at the bottom of the housing and the fixed connection of the upper free edge of the shaft on the shaft and rollable mounted flexible surface element is provided in a simple manner, a mechanism that ensures a safe, automatic extension of the flexible surface element before the access contact and the Outgoing contact allows when the lid is opened. Likewise, it is ensured, preferably by an automatically operating roll-up mechanism on the shaft, that the flexible surface element is wound up again on the shaft when the cover is closed.

The invention will be explained below with reference to the drawings. Show it:

1 : Longitudinal view of an embodiment of the NH bar according to the invention with the lid closed.

2 : NH bar according to 1 with partially opened lid.

3 : NH bar according to 1 with the lid fully open.

4 : Top view of the protected with a protective cover access contact of NH bar according to 1 to 3 with the lid fully open.

The 1 to 4 show an embodiment of the invention NH bar 1 ,

The NH bar 1 is used in a known manner for the field of power supply for load distribution and selective protection of power lines.

The components of the NH bar 1 are in a substantially cuboid housing 2 integrated, which is open at its top, which has a housing opening 2a having. The housing opening 2a can with a lid 3 be closed, which has a hinge connection 4 with the housing 2 connected so that the lid 3 is pivotally mounted and between a closed position in which the lid 3 the housing opening 2a completes ( 1 ), and an opening position in which the lid 3 is almost vertical and the housing opening 2a completely releases ( 3 ), can be moved.

To remove the lid 3 is at the top of a handle 3a intended. The housing 2 and the lid 3 are preferably made of an electrically insulating plastic.

At the bottom of the lid 3 the NH bar 1 is a NH fuse 5 attached, which at their longitudinal ends in each case a metallic, plate-shaped contact element 5a having.

On opposite side walls of the housing 2 the NH bar 1 are arranged contacts. A first contact forms an access contact 6 to connect to the NH bar 1 guided lines is used. A second contact forms a departure contact 7 of which lines from the NH strip 1 depart.

Every contact points, as in 4 for the access contact 6 shown, contact terminals 8th on both sides of a contact slot 9 in which a contact element 5a the NH bar 1 can be introduced.

If, as in 1 shown, the lid 3 the NH bar 1 is closed, is the NH fuse 5 oriented in the horizontal direction so in the interior of the housing 2 in that the contact elements 5a in the contact slots 9 the access contact 6 and the departure contact 7 grab, creating over the NH fuse 5 a connection between the access contact 6 and the departure contact 7 is made.

Is the lid on the other hand 3 to the opening position ( 3 ) is the NH fuse 5 from the access contact 6 and the departure contact 7 lifted so that they are exposed.

Would a metallic object like a wrench with the lid open 3 fall into the interior and at the same time the access contact 6 and the departure contact 7 contact electrically, would create a dangerous short circuit between these contacts.

In order to avoid such dangerous situations, is in the NH bar according to the invention 1 a protective device in the form of a protective cover for the access contact 6 intended.

The protective device comprises a roller blind 10 which is a wave 11 having a retractor, by means of which a flexible surface element 12 in the form of a net, a foil or a textile surface on the shaft 11 can be rolled up and unrolled.

The blind 10 is on the bottom of the case 2 the NH bar 1 immediately before the access contact 6 stored.

How very clear in 4 are shown at the top of the flexible sheet 12 two bands 13 attached. These consist of a flexible but not elastic material. Generally, as bands 13 also cords and the like can be used. Every band 13 is with a longitudinal end on the flexible surface element 12 and with the second free end at the bottom of the lid 3 attached. These are at the bottom of the lid 3 suitable fasteners 14 provided, which are formed in the simplest case of a hook or eyelet.

How out 4 Obviously, both bands are 13 of equal length. The length of the bands 13 is dimensioned so that when the lid is closed 3 the NH bar 1 the flexible surface element 12 completely on the shaft 11 is wound up and the tapes 13 with low tension from the lid 3 to the bottom of the case 2 extend. Because in this position the flexible surface element 12 completely in the roller blind 10 is retracted, is the access contact 6 free, that is he is not the flexible surface element 12 blocked. Thus, the contact element 5a the NH fuse 5 as intended in the contact slots 9 the access contact 6 grab as in 1 shown.

When opening the lid 3 be with the pivotal movement of the lid 3 the bands 13 moved up, creating the flexible surface element 12 from the wave 11 is rolled off. 2 shows an intermediate position in which the lid 3 only slightly pivoted upwards. Corresponding to the pivoting angle is also the flexible surface element 12 something from the wave 11 extended.

Once the lid 3 is completely open, that is in an open position according to the 3 and 4 is pivoted, is the flexible surface element 12 maximum of the wave 11 of the blinds 10 unwound, leaving the flexible surface element 12 as in the 3 and 4 presented the access contact 6 , in particular the contact terminals 8th on both sides of the contact slot 9 completely covered. This is the access contact 6 secured against contact with metallic objects, so no short circuit through one in the contact slots 9 the access contact 6 and departure contact 7 incident metallic object can arise.

If the lid 3 is closed again, rolls the flexible surface element 12 automatically on the shaft 11 of the blinds 10 on, that is the flexible surface element 12 is completely on the shaft 11 rolled up when the lid 3 the housing opening 2a (as in 1 shown) completes.

LIST OF REFERENCE NUMBERS

1

NH-bar

2

casing

2a

housing opening

3

cover

3a

Handle

4

articulation

5

NH fuse

5a

contact element

6

access member

7

outgoing contact

8th

Contact terminals

9

contact slots

10

roller blind

11

wave

12

flexible surface element

13

bands

14

fastener

Claims (8)

NH bar ( 1 ) with a housing opening ( 2a ) housing ( 2 ) and one on the housing ( 2 ) pivotally mounted lid ( 3 ), by means of which the housing opening ( 2a ) is lockable, wherein in the housing ( 2 ) an access contact ( 6 ) and outgoing contact ( 7 ) and on the lid ( 3 ) an NH fuse ( 5 ), whereby only when the lid is closed ( 3 ) the NH fuse ( 5 ) with the access contact ( 6 ) and the outflow contact ( 7 ) is contacted, one by the opening of the lid ( 3 ) is provided automatically actuable mechanical protection device, which is provided by a flexible surface element ( 12 ) formed on a shaft ( 11 ) is rolled up and down, wherein by means of the protective cover with the lid open ( 3 ) access to either the access contact ( 6 ) or the departure contact ( 7 ) is locked. NH bar ( 1 ) according to claim 1, characterized in that the mechanical protection device is designed as a protective cover, which the access contact ( 6 ) and outgoing contact ( 7 ) with the lid open ( 3 ) covers. NH bar ( 1 ) according to claim 2, characterized in that the protective cover when opening the lid ( 3 ) is automatically extended from a closed position. NH bar ( 1 ) according to claim 3, characterized in that the protective cover when closing the lid ( 3 ) is automatically retracted to the closed position. NH bar ( 1 ) according to one of claims 1 to 4, characterized in that the flexible surface element ( 12 ) is formed by a net, a film or a textile surface. NH bar ( 1 ) according to one of claims 1 or 5, characterized in that the shaft ( 11 ) at the bottom of the housing ( 2 ) is stored. NH bar ( 1 ) according to claim 6, characterized in that the shaft ( 11 ) a roll-up mechanism for the flexible surface element ( 12 ) having. NH bar ( 1 ) according to one of claims 1 to 8, characterized in that at the upper, free edge of the flexible surface element ( 12 ) Bands ( 13 ) are attached to the lid ( 3 ) are connected.

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