Patent Publication Number: US-5293013-A

Title: Switching cable

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a cable for use in connecting a computer to a peripheral equipment or the like. 
     2. Description of the Related Art 
     Conventionally, when connecting a computer to a peripheral equipment by a cable, it is a common practice to fix the cable at both the sender&#39;s side and the receiver&#39;s side, which is a straight connection. 
     Whereas when using a cable in data communication between computers or in connection between a computer and a scanner, the sending terminal and the receiving terminal are mutually reversed to exchange data, which is a reverse connection. 
     Heretofore since there are such two kinds of cable connections, a wrong cable has oftentimes been taken. A shop must have both kinds of cables, which increases the number of goods in stock. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to provide a cable which is usable both in straight connection and reverse connection. 
     According to this invention, there is provided a switching cable for connecting a peripheral machine or a computer to another computer, the switching cable comprising: a pair of connectors each having a plurality of pins; a plurality of wires each adapted to connect the individual pins of one of the connectors with the individual pins of the other connector; and a switching device mounted on at least one of the connectors for a switching over the connecting state of the wires. 
     With this arrangement, it is possible to set selectively straight connection or reverse connection by turning the switching device, depending on the kind of equipment to which a computer is to be connected. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a switching cable according to one embodiment of this invention; 
     FIG. 2 is a perspective view of a modified switching cable according to another embodiment of the invention; and 
     FIG. 3 is a circuit diagram showing the manner in which wires of the switching cable are to be selectively connected. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows a switching cable 1 of the first embodiment. The switching cable 1 has a pair of opposite connectors 2, 3; on one connector 2, a rotary switch 4 serving as a switching device is mounted for selectively switching over the connection of internal wires between straight (S) and reverse (R) connections. 
     FIG. 3 is a circuit diagram showing the manner in which the internal wires of the switching cable 1 are to be selectively connected. Each connector of this switching cable 1 is composed of 25 pins; five sets of pins, i.e., Nos. 2 and 3, Nos. 4 and 5, Nos. 6 and 20, Nos. 17 and 24, and Nos. 7 and 8 are switched over between straight connection (S) and reverse connection (R) by the rotary switch 4, which includes nine circuits and two contact points. 
     The switching device should by no means be limited to the rotary switch 4, and may be a slide switch 5 as shown in FIG. 2. The switching device may be mounted on each of the opposite connectors. 
     Since the switching cable of this invention can be switched over between straight connection and reverse connection according to the use, it is free from the conventional problem that a wrong cable might be taken out of two kinds of cables, and it is also possible to reduce the number of goods in stock in a shop to half. 
     In use, when a computer and a peripheral equipment are to be connected to one another by the switching cable 1, it is necessary to connect the sending terminal of the computer to the receiving terminal of the peripheral equipment and to connect the receiving terminal of the computer to the sending terminal of the peripheral equipment. 
     In some of computers or peripheral equipments, even when the sending terminal of one computer is connected to the sending terminal of the other or when the receiving terminal of one computer is connected to the receiving terminal of the other, yet the same result as the one obtained when connecting the sending terminal to the receiving terminal and vise versa can be obtained, depending on the functions of the internal circuits. If this is the case, the switching cable 1 is switched over to the straight connection (S). In other words, with some pins of one connector directly connected to the corresponding pins of the other, the sending terminal of one computer is connected to the sending terminal of the other or the receiving terminal of one computer is connected to the receiving terminal of the other. 
     In other computers or peripheral equipments not having the above-mentioned functions of the internal circuits, the switching cable 1 is used as switched over to the reverse connection (R). Namely the state of connection of the individual pins between a pair, of companion connectors is switched over, whereby the sending terminal of one computer is directly connected to the receiving terminal of the other via the switching cable 1.