The present invention relates to a switch matrix for making cross-connections for telephone lines and, more particularly, to a switch matrix comprising a plurality of switch components operated by a drive mechanism
In a switch matrix for making cross-connects within a telecommunications network using a drive mechanism to connect a plurality of cross-connect points, for example, in a rotary type switch, a failure of the drive mechanism will result in several cross-connect points being inaccessible for making connections. If these cross-connect points are oriented towards a telephone line, the line will not be able to be switched over. The problem can sometimes be corrected by orienting the switch in the other direction; however, in the above case the desired function cannot be applied in the line direction. However, it is possible to design a break or disconnect line function into the example accordingly.
There is a need to provide cross-connect redundancy in switch matrices to enable the switch matrix to continue to operate when the drive mechanism fails. There are various known means by which to switch copper lines in a telephone network, such as using electromechanical relays or robotic pick-and-place solutions that places conductive pins in holes to make the cross-connect. However, none of the prior art solutions have redundancy capability, i.e. the cross-connect in the switch matrix cannot be switched over to a backup when there is a failure.
An object of the present invention is to provide a solution for the aforementioned redundancy problem and provide a switch matrix that will continue to be operable in the event of a failure. The invention provides the addition of redundancy functionality to a switch matrix.
The invention relates to a switch matrix arrangement that comprises a plurality of switching components. The components are oriented in the input line direction whereby the cross-connect is made by means of the switch component in the line direction. Another backup or redundant switch component, oriented in the opposite direction, is connected to the plurality of switching components whereby in case of a failure in any of the switch components, the lines are always accessible.
The redundant component is connected to a further switch component in the line direction and is connected to the switching network's output lines. In this way all outputs can be accessible. This arrangement eliminates the need for extra line or cable pairs to be provided. This is important because in some cases a cable with additional pairs is required.
This invention functions relatively straightforwardly, reliably, and requires no additional cabling.
The figures show the principle of the invention. A switch matrix with a plurality of switch components 1 are arranged on a PCB. The matrix can be designed for accommodating, for example, 20×20 lines, i.e. 20 switch components 1. Each component consists of a number of first contact points (20 in this example), located in a straight line and connected by an incoming line (A, B . . . T). Parallel to this row of contact points, that is another row of contact points, which are connected by outgoing line (a,b, . . . t). The corresponding contact point in each of the switch components is connected to the same outgoing line a, b, . . . t. A contact block or sledge 2 can move parallel to the contact point rows and connect an incoming line with a selected outgoing line via corresponding contact points. By way of example, as shown in
Only one line per line is shown in the figure for simplicity. In practice there are two lines per line making up a line pair, whereby the switch matrix includes double rows of contact points, connected to the second incoming line and the second outgoing line, respectively, and two mutually moveable contact blocks 2. Furthermore, each of the switch components can include two other rows of contact points with moveable contact blocks that move together with the earlier described two blocks. These latter mentioned contact points are connected by a common incoming line and outgoing lines respectively, which can be used for a positioning function, which can be useful in a cross-connect apparatus where one wishes to determine the line connections.
Referring to
By way of example, if switch component 1 for line G fails, the switch component 4 will be oriented so that the contact block makes contact over input G with output line 5, which provides a connection for the input in switch matrix 6 to one of the outputs a,b, . . . t in the switch matrix. Thus, line G can be redirected to any selected outgoing line despite a failure in switch component 1.
The invention may contain modifications that will occur to those skilled in the art and that such modifications and variations are within the scope of the invention which are only limited by the following claims.
Number | Date | Country | Kind |
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0301439-6 | May 2003 | SE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IB2004/050739 | 5/18/2004 | WO | 00 | 1/15/2007 |