DE202014003001U1 - Simultaneous use of a 2-wire cable for the transmission of data and supply voltage between an electronic lock and an electronic key - Google Patents

Abstract

Simultaneous use of a 2-wire line for transmitting data and supply voltage between an electronic lock and an electronic key, characterized in that a switch (1) in the connecting line (3) switches between data traffic and supply voltage. The switch (1) is located in the key (2) and is controlled by the key controller (4). The supply voltage is fed from the battery (5) located in the key (2). The key (2) switches constantly between data traffic and supply voltage. If the connection to the lock is established, the lock controller (8) reports during the data traffic phase, the key controller (2) now decides whether to continue in data traffic or to switch to supply voltage.

Description

The multiple use of lines, especially in communications technology, has long been achieved with a large number of technical solutions (eg hybrid circuit, carrier frequency method, multiplexer). A special requirement is the transmission of data and supply voltage via a line. There are solutions such as As the MicroLAN Dallas. The bus is held high (5 V). The receivers on the bus charge a small capacitor with this high potential. When the bus is switched to traffic, the receivers are powered by this capacitor during a low bit and offloaded at the next high bit. However, this type of parasitic feeding is only possible for very small consumers. If more power is required, this power must be brought to the consumer via separate lines. So it is z. B with PoE (Power over Ethernet) possible to deliver up to 25 W to terminals. For this purpose, however, separate wires are used in the cable used.

The invention specified in claims 1 to 4 is based on the problem that in addition to the bidirectional data traffic and a supply voltage to be transmitted via a line. In this case, a power of up to 3 W to realize an electronic lock with electromechanical components such. B. solenoids o. Ä. To directly control. The bitrate for traffic should be at least 9600 bps or 1200 baud (8 bit / baud). The cable lengths to be realized are largely determined by the cable cross-section and the frequency-dependent attenuations. However, it should be possible to realize a cable length of 10 m with a simple 0.14 mm ² twisted pair cable.

This problem is solved with those listed in the protection claim 1 to 4 features.

With the invention it is achieved that over a 2-wire line (ground and signal) a bidirectional data traffic of min. 9600 bps and a supply voltage of 3.3 V and a current of at least 1 A (3.3 W) is transmitted. For this we put the line after contacting the electronic key with the lock on the active side (electronic key with power supply) and after entering the start button but before starting the data communication to operating voltage. A large capacitor (about 10 mF) on the passive side (electronic lock without power supply) is charged here, the passive side goes into operation. After a time t (= capacitor is full!), The active side switches the line to traffic. It starts with the data exchange in the direction of the passive side. The passive side answers in turn. The dialog for the exchange of authorizations is processed. For the entire duration of this communication, the passive side is fed via the capacitor. Since this communication i. d. R. lasts only a few milliseconds, the capacitor discharges only insignificantly. If the authorization of the key is signaled by the lock, the active side (key) switches the line to operating voltage and the electromechanical blocking element (eg lifting magnet) connected to the lock is supplied with enough current from the key to be activated. After the opening time, the active side (key) switches the line back to traffic. After decontacting the key, the initial state is restored.

An embodiment is based on 1

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1 Block diagram with active side (key), conduction path with contact point and passive side (lock) with electromechanical blocking element.

1 shows that a switch ( 1 ) on the active side (key) ( 2 ) the connection line ( 3 ) optionally between operating voltage from the battery ( 5 ) and can switch data. The control of the switch ( 1 ) is controlled by the key controller ( 4 ) on the active side ( 2 ) accepted. The connection between the active side (key) ( 2 ) and the passive side (lock) ( 6 ) is connected via the connecting line ( 3 ) and the contact point ( 7 ) produced. On the passive side ( 6 ) is the line on the lock controller ( 8th ) connected. The lock controller ( 8th ) also controls via the switching stage ( 9 ) the electromechanical blocking element ( 10 ). The charging capacitor ( 11 ) ensures, on the one hand, the lock controller ( 8th ) is supplied with power during the data traffic, on the other hand it serves as a power source for the blocking element ( 10 ).

Claims (4)

Simultaneous use of a 2-wire cable for transmission of data and supply voltage between an electronic lock and an electronic key, characterized in that a switch ( 1 ) in the connection line ( 3 ) switches between data traffic and supply voltage. The desk ( 1 ) is in the key ( 2 ) and is controlled by the key controller ( 4 ) controlled. The supply voltage is from that in the key ( 2 ) ( 5 ). The key ( 2 ) constantly switches between data traffic and supply voltage. If the connection to the lock is made, the Lock controller ( 8th ) during the traffic phase, the key controller ( 2 ) now decides whether to continue in the data traffic or to switch to supply voltage. Simultaneous use of a 2-wire line according to claim 1, characterized in that the supply voltage of the lock controller ( 8th ) via the charging capacitor ( 11 ) is buffered. The charging capacitor ( 11 ) is dimensioned so that it can supply enough energy during the traffic phase. Simultaneous use of a 2-wire line according to claim 1 or 2, characterized in that the charging capacitor ( 11 ) as a current storage for the inrush current of the blocking element ( 10 ) serves. The charge of the charging capacitor ( 11 ) when switching through the switching stage ( 9 ) for the moment of actuation of the blocking element ( 10 ) used. Simultaneous use of a 2-wire line according to claim 1, 2 or 3, characterized in that after completion of the traffic (all permissions were exchanged and an opening authorization of the corresponding key detected), the key controller ( 4 ) the switch ( 1 ) switches to supply voltage. The lock controller ( 8th ) now switches the switching stage ( 9 ) by. For the tightening torque of the locking element ( 10 ), the charge of the charging capacitor ( 11 ), then the through-connected supply voltage ensures the safe operation of the blocking element ( 10 )

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