SE469410B - Portable device for enabling a person with serious hearing impairment to use conventional telephone apparatus in the public telephone network - Google Patents

Abstract

Mobile device for enabling a person with serious hearing impairment to use the public telephone network, where the person with impaired hearing transmits speech signals from his telephone apparatus to the recipient and by means of the device receives character signals from the recipient's telephone apparatus. The recipient is assumed to have a telephone apparatus which can transmit character signals. The device comprises a microphone 2 with amplifier 18. The microphone can be placed on the earphone of the conventional telephone receiver which the person with impaired hearing uses. An optical signal device 19, 20 is connected to the microphone amplifier 18 which device indicates the ringing, reply and engaged signals to the person with impaired hearing. A character signal receiver 21 is also connected to the microphone amplifier 18, arranged to receive character signals from the recipient's telephone apparatus and to generate a binary code which by means of an associated erasable read only memory 23 and associated control circuits 22, 26, 27, 28, 29, 30 are used to convert the received character signals into optically readable characters, letters or numbers, which are presented on a display 24 connected to the read only memory 23. <IMAGE>

Description

The invention is mainly characterized in that the portable device comprises a microphone with associated amplifier, which is acoustically applicable to the handset of the telephone set used by the hearing impaired, an optical signal means indicating the hearing, answering and recording signals of the hearing impaired person and a character listening receiver. display, whereby the character receiver receives signal signals from the receiver's telephone in a manner known per se, converts the character signals into optically readable characters, letters or numbers, and presents these in the display.

The device consists of a small battery-powered unit with an associated microphone which is connected to the unit and in transport mode attached to it. The unit is designed as a small box with a display for at least 16 characters and a signal lamp in the form of an LED on the front. The box has battery compartments for dry batteries or rechargeable cells of, for example, type H6 and also a holder for the microphone. The size of the box is such that the unit can easily - be carried in a pocket or in a handbag. The microphone holder is combined with a cord winder for the microphone cord and switch function that starts the unit when the microphone is taken out of its holder. The device will henceforth be called Telehjälp.

The hearing-impaired person uses Telehjälp as he has to get in telephone contact with someone. He may be outside his home environment and be in a work environment, public environment or at someone's home and may be in need of telephone contact with a counterparty. He then seeks out a telephone (any available) to call the other party who he knows has a dial telephone. Before the call, he took out his Telehjälp and released the microphone from his holder. The device is then activated.

The microphone is applied to the earphone of the intercepted handset. The response tone causes the LED to light up on the front of Telehjälp. When the hearing-impaired person dials the telephone number, the LED stops lighting but lights up again at the same time as the tone indication of the ring signal. During a busy tone, the LED lights up at a faster rate and the hearing impaired person can see the busy number on the telephone. When the caller answers, this is indicated by a flickering light on the LED. The hearing impaired person can now make wishes or questions to the caller. The request is made so that the caller can in the simplest case confirm or reject a request or ask with the push of a button on the keypad. Which button does the hearing-impaired .ß m v: rs - .. à c: inform about. In other words, the hearing impaired controls communication. Each digit that is printed is displayed in Telehjelp's display. It is also possible to transmit text messages to Telehjälp's display. The caller must then use the keypad's pre fi x keys together with the number keys and also know the current key selection schedule. This will be described in more detail below.

Keypad telephone with dial tone code can, as is well known, be used to, for example, check the account balance in your own bank account. In addition, the use of dial tone code for assistance to the hearing impaired has been limited to permanent installation in the home. Because Telehjälp is portable and can be used on all types of telephones, the invention is an aid for the hearing impaired, which gives, as mentioned, great freedom and the opportunity to use the same.

A more detailed description of the invention will be given in connection with Figures 1, 2, 3, and 4. Figure 1 shows an example of an embodiment of Telehjälp. The microphone 2 is connected to the unit 1 via a cable with plug 3 and jack 4. On the front of the unit there is the LED indicator 5, the display 6 and the storage compartment 7 for the microphone in transport mode. The battery compartment is covered by a lid 8. Fig. 2 shows Telehjälp 1 in operating mode with the microphone 2 applied to the handset's headphone by means of, for example, a rubber strap.

The basic structure of Telehjälp is shown in the block diagram Fig. 3.

The device contains a microphone 2 which is connected to microphone amplifier 18. This in turn is connected partly to a control circuit 19 for a LED indicator 20 and partly to a tone selection detector 21 which consists of a standard DTMF receiver.

DTMF stands for Dial Tone Multi Frequency. Each pair of tones entering the DTMF receiver produces a 4-bit code. This code is fed in a manner known per se, partly into a block 22 and partly into a block 23 which consists of a erasable read-only memory, a so-called E-PROM. In this read-only memory is stored the 8-bit code needed for the display 24 (display) to be able to present the desired characters. With the aid of this read-only memory, a large number of different characters can be displayed in the display 24. 469 4iÛ The device further comprises blocks 22, 25, 26, 27, 28, 29 and 30 known per se. Block 22 contains, among other things, two JK flip-flops. and comparators.

The position of the JK flip-flops determines the way of addressing the read-only memory. The comparators make it possible to distinguish the 4-bit code given from the DTMF receiver 21 when either the prefix key * or # is pressed on the keypad. The comparators may in turn affect the J and K inputs on the JK flip-flops in order to obtain the correct addressing mode for the read-only memory 23 and the correct 8-bit code to be transmitted to the display 24. Block 25 is a power supply part which ensures that the correct supply voltages are applied to the device. . At the start of the device, block 25 affects block 26, which contains, among other things, an oscillator and a counter which transmits an update program from the read-only memory 23 to the display 24. In addition, the flip-flops and counters included in the blocks are reset. Block 27 contains, among other things, a NAND gate, which, after a complete character has been transmitted to the display 24, sends a reset pulse to the JK flip-flops in block 22. Block 28 contains a 16-counter, which counts the number of characters from the beginning of the message. When 16 characters have been transferred to the display 24 and this is full, the counter 28 notifies blocks 29 and 30. Block 29 contains control logic for the reading from the read-only memory 23 and block 30 contains control logic for the reading in the display 24. The 16-counter influences the control logic 29 and So that, instead of entering new characters from left to right in the display 24, new characters are subsequently entered at the far right. Previously entered characters are simultaneously shifted one step to the left for each newly entered character. Continuous inscription is thus obtained with new characters entered from the right of the display 24.

With the help of the keypad on a standard dial telephone, both numbers and letters can be transferred to the display on Telehjälp in a known manner. The meaning of the buttons regarding transmitted characters to the display is determined by the 3-bit codes read in the read-only memory 23. These can be selected almost arbitrarily. If, for example, one starts from an international standard that has been accepted in several places in the world, the character content of the buttons looks like in Fig. 4.

If you adapt the reading memory to this key scheme, a single press of a number key can give a printed number in the display. If you want the letter J on the display in Telehjälp, first press prefix * and then 5. If you want the letter L, first press prefix # and then 5 and if you want to write a K, press prefix * plus # and then button 5. Other letters generated in a corresponding manner. The international standard does not contain the letters Å, Ä 4 6 9 4 l 0 and Ö which are in Swedish. These can then, for example, be placed on button 1, which is free. Spaces between characters can be created, for example, by double-clicking the prefix *. This arrangement, as exemplified, depends entirely on how the read-only memory 23 is programmed. If the unit is to be used internationally, the arrangement shown may be appropriate.

The portable device described above entails a significant improvement in the possibilities for severely hearing impaired people to use existing public telephones, both in the home environment, in the workplace and in public places. The invention is of course not limited to the details stated in this description.

Claims (4)

469 4iÜ PATENTKRAV Portable device for enabling severely hearing impaired people to use conventional telephone sets in the public telephone network, both in the home and work environment and in the public environment, the hearing impaired transmitting speech signals in the usual way through the used telephone set to a receiver and receiving signal signals on the device. per se known manner from the receiver's telephone set, which is assumed to be signal transmitting, characterized in that the portable device comprises a microphone (2) with associated amplifier (18), which is acoustically applicable to the headphone in the handset used by the hearing impaired person. , an optical signaling means (19, 20), which indicates the call, answer and pick-up signals of the hearing impaired person and a sign signal receiver (21) with associated display window (24), the sign signal receiver (21) receiving sign signals from the receiver in a manner known per se. telephone, converts the character signals into optical reading ara characters, letters or numbers, and presents them in the display (24). Device according to claim 1, characterized in that the microphone (2) and amplifier (18) are combined into a unit, which is detachably mounted on the device in such a way that the device automatically comes into operation when this unit is released. Device according to claim 1, characterized in that the optical signal means comprises an LED (5). Device according to claim 1, characterized in that the control circuits for read-only memory (23) and display (24) comprise a counter (28) which is adapted to the number of possible characters in the display (24), which enables successive reading of received characters and which at full display successively replaces previously received characters .ey