DE9316584U1 - Electrical locking device for telecommunication devices - Google Patents

Description

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DiPL-iNG. CONRAD KÖCHLING /''"&Lgr;*- -jj -I*-'***]-. &Iacgr;

DiPL-iNG. CONRAD-JOACHIM KÖCHLING "*" "

r,«r, ~ r, „_{&Lgr;&eegr;&Lgr;} ,, Note: Wilhelm Rutenbeck

P, O. Box 2069, D-58020 Hagen

FleyerStrasse 135, D-58097 Hagen GmbH. & Co.

FaiSrs^o ⁴ " ⁸⁵⁰³³ Niederworth 1-10

Telegrams: Patent Cook Hagen

Accounts: Commerzbank AG, Hagen3515095(8LZ 45040042) &eegr; _ cqctq

Sparkasse Hagen 100012043 (bank code 45050001) ^U ->^ö;:)/y

Postgiro: Dortmund 5989-460 (bank code 44010046) __

VNR: ¹ J ⁵ IJl

Serial No. 1.1214/93

from 2.8........0.k.t.Q..b.e.r I.

CJK/Hi.

Electrical locking device for telecommunications equipment

The invention relates to an electrical locking device for telecommunications devices, consisting of a circuit arrangement that can be switched on between the connecting conductors of the telephone network and a telecommunications device, e.g. a telephone, whereby the circuit arrangement between the network input and the device output preferably has a reverse polarity protection circuit and further circuit elements.

In the prior art, locking devices are known which can be operated, for example, by means of a key switch, whereby when the key switch is closed, the device is switched transparently so that the downstream terminals can be used for outgoing and incoming calls, while when the key switch is open, outgoing connections are locked but incoming connections can be queried without being locked.

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Based on this state of the art, the invention is based on the task of creating a freely programmable blocking device that not only enables outgoing connections to be blocked, but also enables only certain outgoing connections to be blocked. The blocking device should not delay the actual dialing process and thus the connection setup for outgoing connections, or should only delay it insignificantly.

To solve this problem, it is proposed that a loop monitoring circuit, a ring detection circuit, a dial tone detection circuit and a DTMF dial recording circuit are connected as part of the circuit arrangement in parallel to the conductors connecting the mains input to the device output, that these circuits are connected via signal lines to a processor control which controls a loop separation circuit and which can be switched off, into the blocking function or into programmed blocking mode via coded input signals,

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that the processor control communicates with a non-volatile electrically erasable memory module into which the telephone number to be blocked or the telephone number to be released can be stored via a coded input station, whereby when the processor control is switched off the circuit arrangement is transparent for incoming and outgoing calls,

when the processor control is switched to the blocking function, the circuitry is completely blocked for outgoing operation and/or only released for emergency numbers in outgoing operation and is transparent for incoming operation, when the processor control is switched to programmed blocking operation, the circuitry is transparent for incoming operation and only transparent for programmed numbers for outgoing operation and blocked for other numbers or only blocked for programmed numbers and transparent for other numbers, whereby when dialing in the outgoing direction, the dialed digits are recorded and compared with digits of blocked or free circles stored in the memory, and the

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Connection establishment is interrupted by disconnection if a number or sequence of numbers is selected that is programmed as a blocked circuit or an impermissible free circuit.

In order to avoid the blocking device being able to be bypassed, particularly in the so-called DTMF method, by dialing the corresponding sequence of numbers before the dial tone is detected and thus establishing the line connection, it is proposed that an attenuator be connected in parallel to the conductors of the device, which is switched on in outgoing operation after the handset of the telephone has been picked up and the loop has been closed to suppress dial tones (pulse or DTMF) and activates the dial tone detection circuit, whereby the attenuator is switched off after receiving a dial tone within a definable period of time.

Furthermore, it is preferably provided that the processor control is connected via a signal line to an audio input, which is parallel to the conductors

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and by means of which an error tone can be transmitted to the telephone receiver when a digit or sequence of digits of a blocking circuit is dialled.

The freely programmable locking device created in this way enables outgoing connections to be blocked on a telephone connection, whereby three operating states can be set by the user. A keyboard and a display connected to it are preferably provided for operating the locking device, whereby the keyboard can only be operated for programming purposes if a PIN number (personal identification number) has been entered beforehand. In addition to number keys from 0 to 9, the keyboard includes program keys and in particular selection keys for the functions lock off, total lock, program lock and PIN number.

The normal function "Off" switches the locking device transparently so that the downstream devices can be used without restrictions. In the locking function

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dialing for outgoing calls, except for emergency numbers, is blocked. Incoming calls can be queried .

In the program lock function, individual phone numbers can be excluded from the lock by programming lock or unlock circuits. The electrical lock device is connected to an external power supply via a power supply unit. For the emergency function, i.e. when the power supply is interrupted, the lock device is powered via the telecommunications wires, although it is then not possible to change the memory. In emergency mode, the lock device therefore remains in the set operating state. The operating states can be entered and changed using function keys and by entering a personal identification number. User-friendly programming is possible using the number keys, which is supported by the corresponding display. The operating states can also be shown on the display.

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The locking device can be plugged into an N socket of a TAE via a connecting cable. Preferably, a locking lock is provided, which can prevent the locking device from being separated from the TAE.

The locking device can also be operated in combination with automatic switches and on private branch exchanges. The locking device and the programming of the locking or unlocking circuits are powered by a plug-in power supply unit, whereby in emergency operation the locking device is powered from the telephone network connection line. In this state, data cannot be changed.

The locking device is bilingual, i.e. suitable for connections using pulse dialing as well as multi-frequency dialing. It is designed to be 16 kHz stable.

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In order to largely rule out manipulation of the locking device, a seal must be provided. The locking device can be designed in the form of a closed device, in which the corresponding connecting screws are provided with seals that can only be removed if there is noticeable damage.

A structural design of the locking device can be designed in such a way that a housing is formed consisting of a cap and a base plate. A key selection block with two control keys and four status keys can be arranged in the cap, with the display also being embedded in the housing. The cover cap can be screwed to the base plate on the underside. The electrical or electronic assembly consists of a circuit board with electronic components, display, switch mat for the key selection block and function keys as well as sockets for the cord and plug-in power supply. It is attached to the base plate.

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The blocking device can normally be connected to the connection lines with four wires. It can be operated on main and secondary connection lines. When using the blocking device in systems with an earth button as access to the main connection line, a five-wire connection cord must be used. The TAE must be connected to earth accordingly. An optional evaluation circuit (e.g. plug-in as a sub-assembly) can detect earthing of the a-wire or earthing of the a and b-wire. The processor control processes the detected earth button press and treats it like entering the digits for the outside line.

In the normal function (switched off) the locking device behaves transparently, i.e. the telephone connection can be used without restrictions in both incoming and outgoing directions. In the total lock or program lock functions the operating modes defined in the device-specific requirements of the Federal Post Office are possible.

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Total blocking means a complete outgoing block. Only incoming calls can be accepted. If you try to make an outgoing call, the connection is disconnected. Exceptions are the emergency numbers, for example 110, 112, 115 and 19222.

In program lock mode, incoming calls can be accepted without restrictions. When attempting to dial in the outgoing direction, the dialed digits are monitored and compared with the blocked or unblocked areas previously saved by the user. After dialing the digit of a number that was programmed as a blocked area, the connection is aborted by disconnection. The blocked or unblocked area numbers are entered using the dial pad with special keys. The LCD display, preferably with 16 digits, serves for convenient user guidance.

It is possible to switch on the different operating modes and program the device if a four-digit code number (PIN) has been entered beforehand.

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The circuit distinguishes between incoming and outgoing calls using ringer detection and dial tone evaluation. The loop monitoring detects that the handset of the connected terminal has been picked up (loop closure). An attenuator is then switched on to suppress any dialed digits and the dial tone evaluation is activated. If a dial tone is detected during a certain time, it is an outgoing call. The attenuator is switched off and the DTMF dialing is activated. The evaluation of the pulse dialing is carried out using loop monitoring. When a call is made from the connected telephone, the process control (microprocessor) compares the dialed digits with the blocked or free circuits stored in the memory. If an invalid dial digit is detected, the processor sends an error tone to the telephone via the audio tone coupling and then breaks the loop so that no connection is made or the connection is terminated. If a previously authorized telephone number is dialed,

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the subscriber can make the telephone call without restriction. The circuit then only returns to its basic state when the receiver is hung up. If no dial tone is detected after the loop has closed, it is an incoming call. If the circuit detects an incoming call using the ringer and a loop is also formed during the incoming call, neither the attenuation element nor the dial tone evaluation are activated because it is then definitely an incoming call. When a connection is made, no evaluation of any dial tones is carried out so that, for example, remote queries of answering machines do not lead to the connection being terminated.

As already mentioned above, the power supply is provided by a plug-in power supply unit. In the event of a power failure or an attempt to tamper with the power supply by pulling out the power supply unit, the power supply is provided in emergency mode from the telephone network connection line. In order to avoid blind connections, it is not possible to use the locking device if the loop is closed.

·

•♦

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to be programmed in emergency operation. To ensure polarity-independent operation, a circuit for automatic polarity switching is provided.

The free or blocking circuits are stored in a non-volatile electrically erasable memory module (EEPROM).

As additional protection against calls that are connected manually, a blocked signal (payphone recognition tone) can be sent when the line is occupied in blocked mode. This function can be switched on or off by the user using a procedure.

In the drawing, a block diagram of a locking device is shown in Figure 1. Figure 2 shows a corresponding device with keyboard and display.

Figure 1 shows the line wires La ₁ Lb of the telephone network and the connections a2 and b2 for a telephone or the like. The corresponding connections are

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designed as plug connections and connected internally within the device shown in Figure 2 via lines 1, 2. The circuit arrangement according to Figure 1 has a reverse polarity protection circuit 3 and other circuit elements between the mains input (left in the drawing) and the device output (right in the drawing). In parallel to the conductors 1, 2 connecting the mains input with the device output, a loop monitoring circuit 4 with power supply 5 from the telephone network line, a ring detection circuit 6, a dial tone detection circuit 7, a DTMF dial recording circuit 8 and an audio tone coupling and dial suppression 9 are provided. An additional connection wire E with earth pulse detection 10 can optionally be provided for private branch exchanges with outside line access via earth. A processor control 11 with memory 12, display 13 and keyboard 14 is also provided. The processor control 11 (microprocessor) communicates with the non-volatile, electrically erasable memory module 12, into which data is written via the coded input station

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(Keyboard 14) can be used to store numbers to be blocked or numbers that have been released. The keypad can only be used after a PIN number has been entered. To operate the device, you must first enter the PIN number. The PIN number can also be changed by pressing the PIN button as shown in Figure 2 if the previously valid PIN number has been entered beforehand. The locking device can be switched off using the Off button. The SP button causes a total block for outgoing calls, while the PR button causes a program block for programmed numbers or digit sequences.

The microprocessor 11 is coupled via signal lines to the loop monitoring 4, the ringer detection 6, the dial tone detection 7 and the DTMF dialing recording 8 and, if necessary, also to the earth pulse detection 10. The signals received from these elements are processed in the processor control and, if necessary, used to trigger the audio tone coupling and dialing suppression 9 or to switch on a loop separation 15.

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At 16, a plug-in power supply is indicated, by means of which the usual mains voltage of 230 volts can be transformed to an operating voltage UB of 6 volts, which is then used to operate the locking device. For this purpose, the plug-in power supply is connected to the locking device via a suitable connection.

The locking device allows free programming of numbers to be blocked or released, whereby it is also ensured that the locking device does not result in a time delay for the user for incoming or outgoing calls, provided that the user uses authorised number sequences.

The invention is not limited to the embodiment, but is variable in many ways within the scope of the disclosure.

All new individual and combination features disclosed in the description and/or drawing are considered essential to the invention.

Claims (3)

Rutenbeck 11214/93 -17- Protection claims: 1. Electrical locking device for telecommunications devices, consisting of a circuit arrangement which can be switched between the connecting conductors of the telephone network and a telecommunications device, e.g. telephone, whereby the circuit arrangement between the network input and the device output preferably has a reverse polarity protection circuit and further circuit elements, characterized in that a loop monitoring circuit (4), a ring detection circuit (6), a dial tone detection circuit (7) and a DTMF dial recording circuit (8) are connected as part of the circuit arrangement in parallel to the conductors (1,2) connecting the network input to the device output, that this circuit is connected via signal lines to a processor control (11) which controls a loop separation circuit (15) and which can be switched off, into blocking function or into programmed blocking mode via coded input signals Rutenbeck 11214/93 -18- is, that the processor control (11) communicates with a non-volatile, electrically erasable memory module (12) in which phone numbers to be blocked or phone numbers to be released can be stored via a coded input station, wherein when the processor control (11) is switched off, the circuit arrangement is transparent for incoming and outgoing calls, when the processor control is switched to the blocking function (11) the circuit arrangement is completely blocked for outgoing operation or only released for emergency numbers in outgoing operation and is transparent for incoming operation, when the processor control (11) is switched to programmed blocking mode, the circuit arrangement is transparent for incoming operation and transparent for outgoing operation only for programmed call numbers and blocked for other call numbers or only for programmed call numbers and blocked for other · · Rutenbeck 11214/93 -19- Telephone numbers are transparent, whereby during an attempt to dial in the outgoing direction the dialled digits are recorded at the same time as the digit or pulse sequences sent out to set up the connection and compared with digits of blocking or free circuits stored in the memory (12), and the connection setup is interrupted by disconnection (at 15) if a digit or sequence of digits is dialled that is programmed as a blocking circuit. 2. Electrical locking device according to claim 1, characterized in that an attenuation element is connected in parallel to the conductors (1, 2) of the device, which is switched on in outgoing operation after the handset of the telephone has been picked up and the loop has been closed to suppress dialling tones (pulse or DTMF) and activates the dialling tone detection circuit (7), the attenuation element being switched off after receiving a dialling tone within a definable period of time. Rutenbeck 11214/93 -20- 3. Electrical locking device according to claim 1 or 2, characterized in that the processor control (11) is connected via a signal line to an audio tone coupling (9) which is connected in parallel to the conductors (1, 2) and by means of which an error tone can be transmitted to the telephone receiver when a digit or digit sequence of a blocking circuit is selected.