AU660202B2 - Clinical thermometer with digital and vocal indication - Google Patents

Description

OPI DATE 29/11/93 APPLN. ID 29465/92 III II1 I1 liiil I II AOJP DATE 10/02/94 PCT NUMBER PCT/ES92/00070 11111111 Il lIII AU929465 (51) Clasificacibn Internacional de Patentes5 (11) Nimero de publicaci6n internacional: WO 93/22639 G01K 13/00 Al (43) Fecha de publicaci6n internacional: 11 de noviembre de 1993 (11.11.93) (21) Solicitud internacional: PCT/ES92/00070 (74) odandatario: GONZALEZ GONZALEZ, Pablo; Consulpi, c/ Sants, 42, 08014 Barcelona (ES).

(22) Fecha de presentaci6n internacional: 29 de octubre de 1992 (29.10.92) (81) Estados designados: AT, AU, BG, BR, CA, CH, CS, DE, DK, ES, FlI, GB, HU, JP, LU, NL, NO, PL, RO, RU, Datos relativos a la prioridad: SD, SE, UA, US, Patente europea (AT, BE, CH, DE, P9200889 28 de abril de 1992 ES DK, ES, FR, GB, GR, IE, IT, LU, MC, NL, SE).

(28.04.92) P 9201462 14 de julio de 1992 ES (14.07.92) Publicada Con informe de bzsqueda internacional.

(71) Solicitante (para todos los Estados designados salvo US): Cl- BERVEU, S.A. [ES/ES]; Aribau, 162-166, E-08036 Barcelona (ES).

(72) Inventores; e Inventores/solicitantes (sblo US): URSUEGUIA BALBUE- NA, Andres [ES/ES]; LAZARO CANTABRANA, Armando [ES/ES]; SALVADO USACH, Carlos [ES/ES]; Aribau, 162-166, E-08036 Barcelona (ES).

(54)Title: CLINICAL THERMOMETER WITH DIGITAL AND VOCAL INDICATION (54) Titulo: TERMOMETRO CLINICO CON INDICACION DIGITAL Y HABLADA (57) Abstract The clinical thermometer is comprised of an input from a signal conditioner, which signals are generated by a sensor consisting of a negative coefficient resistance arranged to remain in contact with an area of the human body, a signal translating stage which is comprised of a capacity-resistance load network; a microcontroller which receives the information from the prior stages without having to effect an analog-digital conversion, an output being provided for a voice synthetizer which incorporates parasite suppressing filters and an amplifier stage for the sound signals appropriate to the application and an acoustical transducer such as a loud speaker; and an output for a digital display of the measured temperature. The circuit is designed as a compact arrangement which integrates the stages of conditioning the input signals coming from the probe, the microcontroller and the conditioner of low frequency signals provided to the loud-speaker, said circuit having incorporated a voice synthetizer, a measurement circuit and a microcontroller which sends the corresponding signals to the ideal modules formed by the circuit. Application to the visual and sound indication of the human body temperature.

(57) Resumen Comprende una entrada procedente de un acondicionador de sefiales generadas por un sensor, constituido por una resistencia de coeficiente negativo, dispuesta para quedar en contacto con una zona del cuerpo humano, una etapa traductora de las sefiales que comprende una red de carga resistencia-capacidad; un microcontrolador que recibe la informaci6n de las etapas anteriores sin necesidad de efectuar una conversi6n anal6gico-digital, contando con unasalida para un sintetizador de voz que incorpora filtros eliminadores de parisitos y una etapa amplificadora de la sefiales audibles, en orden a su aplicaci6n y transductor acistico, tal como un altavoz; y una salida para un visualizador numbrico de la temperatura medida. El circuito se construye en disposici6n compacta integrando las etapas aconditionadora de sefiales de entrada procedentes de la sonda, el microcontrolador y acondicionadora de la sefiales de baja frecuencia enviadas al altavoz, conteniendo dicho circuito integrado un sintetizador de voz, un circuito de medida y un microcontrolador que envia las seiiales correspondientes a los m6dulos ideales constituidos por cl circuito. Aplicables a la sefializaci6n visual y sonora de la temperatura del cuerpo humano.

This invention relates to a clinical thermometer with digital and spoken display.

Clinical thermometers are known in the present state of the art, that incorporate a display for the measured temperature values, indicating the said values by means of figures, sometimes along with other indications. In some cases, the known models show legibility problems, specially at a certain distance and to people with sight problems, and this is specially true whenever LCD displays are used.

The temperature gauge to be herein disclosed is further characterised in that it is able to send out intelligible sounds corresponding to the words that indicate the temperature values, so that sightless people and other people with sight deficiency could use the thermometer with no need to read the' values, but by only hearing perception of the said values. To this end, the electronic circuit of this new clinical thermometer includes a voice synthetizer that, at the same time the display shows figures corresponding to the thermal values measured, sends out sound signals which as a whole form words, also indicating the values measured by the device.

In the present patent the structure of a circuit is described on which the measuring device for the human body temperature is based, said circuit being connected, on the one hand, to a probe devised to be placrd in contact with the human body, and on the other hand, to a speaker devised to provide signals corresponding to the temperature values, as well as a display designed to exhibit signs corresponding to the said values.

The proper circuit, reproscnted in the block diagram ac companying the description of the patent, functIonally includ -2- More specifically the invention provides a clinical thermometer with digital and spoken displays, comprising: an input to which a sensor element is attached, the sensor being capable of reacting to variations in temperature, said sensor comprising a negative coefficient temperature (NTC) resistance, a conditioning block for the signals produced by the sensor, a microcontroller block which includes a microcontroller, a voice synthesiser module for generating analogue signals which produce intelligible sounds through a loudspeaker, and a display means for displaying measured values of temperature on a screen, characterised in that, the conditioning block for the signals produced by the sensor includes an RC charge network formed by a precision resistance, the negative coefficient resistance and a capacitor which are directly controlled by the microcontroller without the need of an analogue to digital stage between the sensor and the microprocessor stage.

The thermometer of the invention can be embodied in several ways, one of them consisting of an assembly of discrete components duly built up, though, according to the current physical constitution of electronic circuits, the integrated construction of said components is preferred, in which the components carry out the logic functions originating the operation of the device.

For better understanding of the above description, a drawing is attached in which a practical case of embodiment of the invention is shown, schematically and only as a :20 non-limiting example.

The drawing is a block diagram in which the stages designated with numerals S.correspond to the following parts of the circuit.

Block 1 consists of a thermal probe, that is, a device sensitive to the temperature level and fluctuations, providing an electrically measurable signal which is proportional 25 to the applied temperature. The probe includes an NTC or negative temperature coefficient resistor, characterised in that its ohmic value decreases as the applied "temperature decreases. The system operates according to usage tables supplied by the manufacturer, so that the resistance-temperature ratio is simple and fast.

2 carries out the conditioning of signals produced by the thermal probe and translates the value of the NTC resistor into data directly processable by a microprocessor or a microcontroller built in the device. This circuit is based on a resistance-capacity loading network formed by a precision resistor, the NTC resistor and a capacitor.

950329,p:\opcr\gcp,29465.22 S3 This way the temperature Is directly measured from the microcontroller, with no need to Include an analog/digital converter in the device design. In addition, due to the method used, errors originating from the voltage drop of the batteries and by the condition of the capacitor are eliminated.

Block 3 makes up the microcontroller for the whole system, by means of which the temperature is measured, information is supplied to a set of quartz crystals built in the device, and data necessary to the voice synthetizer are also provided. The microcontroller is custom made and is based on a finite state machine, duly programmed to carry out the general operation algorithm of the thermometer and the communication with the several external modules (synthetizer, quartz crystals and NTC resistor.

Due to the technology used, synthesis module and liquid crystal interface module are physically integrated with the microcontroller, said technology being designated ASIC.

Block 4 ensures the conditioning of analog voice signals, including the filtering and amplification of the said signals. The module forming this stage is integrated into the above mentioned component.

Said stage 4 comprises, in accordance with the above mentioned, a set of filters to eliminate spurious signals that may have been reproduced in prior stages and Includes voice synthetization, the signals of which, being of little amplitude, are magnified by an amplifier built in the same stage, providing the apropriate amplitude for driving the speaker forming stage 5. The latter, in a preferred embodiment, will be built in the thermometer housing.

Display 6 is of the LCD, easy perception type and it will show on screen values corresponding to, for instance, the human body temperature level at a given moment, the maximum and minimum values, and other information.

Amidst the functional parts forming the cllnical thermometer disclosed in the original patent, three parts are invariable and indispensable: the probe for the Immediate sensing of the thermal level of the human body, which is the magnitude to be measured; the speaker for the sending out of sound signnals indicating the measured values, and the display for the visual exhibition of the values. These parts, therefore, will not be the subject of further considerations.

Functional parts defining the essentiality of the circuit forming the clinical thermometer according to the original patent constitute the subject matter of this Patent, which contemplates the practical embodiment of the above mentioned parts.

The matter is, according to the appended claims, to make blocks 2, 3 and 4 of the diagram accompanying the description of the original patent in the form of a unique equivalent block, formed by an integrated circuit of the type called ASIC or specific for the foreseen applicatlon. Said circuit carries out the functions of the above mentioned blocks, with the advantage of simplification and size and weight reduction. The cost of the integrated circuit, even though this is made according to the specifications of the thermometer manufacturer, is also significantly reduced.

When analysing the functional structure of the unified block that now forms the forms the main part of the thermometer constitution, the following subassemblies may be cited, bearing in mind that distinction is merely formal and just in order to follow the input and output signals running, respectively.

1. A voice synthesizer based in ADPCM technology of 3 bits, allowing to obtain an audible frequency range resulting in a voice quality which is sufficient for the output stage.

Said synthesizer is based on a 12 Kbytes memory containing the voice to be synthesized and a machine of synchronous states that directions the memory and coordinates the appropriate messages to shape the signs to be displayed, within a range of values from 32.0 to 42.0 centigrad degrees.

2. A measuring circuit based on a machine of synchronous states that uses digital signals to directly carry out the measurement on the NTC resistor associated to the probe. This allows to eliminate an interface for the analog/digital conversion.

3. A microcontroller, also based on a machine of synchronous states and serving to send the appropriate signals to every ideal module of the circuit, in order to carry out the algorithm or operation necessary for the case: starting of the device, measurement of the physical magnitude, feeding current applied to the voice synthesizer and to the sign display, as well as the disconnection of the device.

It is worthwhile to point out that the measurement method on the thermometer probe allows considering the input signal conditioner as a mere software routine, since there Is no module devised to bring about the analog/digital conversion. The employed method uses directly the signals available In the microcontroller to carry out a frequency-temperature conversion. That is, there does not exist physically an A/D converter module in the Integrated circuit that gathers the above mentioned functional stages.

Temperature measurement is done by computing the number of charges and discharges effected by the NTC resistor on a capacitor and refer ing it to the number of charges and discharges effected on a resistor of known value. From the resulting ratio the NTC value is obtained, and this value corresponds, according to a previously established table, to the temperature of the probe. This measurement method makes it possible to simplify at maximum the related module, as well as to obtain a measurement value which is stable in relation to changes in the feeding voltage (supplied by a set of batteries included in the device housing) and to differences in the ohmic value tolerances of the capacitor used.

A further advantage of the embodiment under description is the very small number of components directly involved with the measurement: just a capacitor, a low tolerance resistor and the NTC resistor associated to the probe.

In a preferred embodiment, the new temperature gauge will comprise a housing showing, in a easily accessible place, the thermal probe arrangement, able to be applied to the human body, the housing including as well the speaker compartment and a set of openings for the output of the generated sounds.

Claims (4)

1. A clinical thermometer with digital and spoken displays, comprising: an input to which a sensor element is attached, the sensor being capable of reacting to variations in temperature, said sensor comprising a negative coefficient temperature (NTC) resistance, a conditioning block for the signals produced by the sensor, a microcontroller block which includes a microcontroller, a voice synthesiser module for generating analogue signals which produce intelligible sounds through a loudspeaker, and a display means for displaying measured values of temperature on a screen, characterised in that, the conditioning block for the signals produced by the sensor includes an RC charge network formed by a precision resistance, the negative coefficient resistance and a capacitor which are directly controlled by the microcontroller without the need of an analogue to digital stage between the sensor and the microprocessor stage.

2. A clinical thermometer as claimed in claim 1, wherein the microcontroller uses its digital signals to perform measurement directly on output from the conditioning stage.

3. A clinical thermometer as claimed in claim 1 or 2, wherein the microcontroller is operable, after computing temperature values based on output from the conditioning 20 stage, to generate output signals which are coupled to said voice synthesiser module and said display means.

4. A clinical thermometer as claimed in claim 1, 2 or 3, wherein said conditioning block, said microprocessor and said voice synthesiser module are formed in a single 25 integrated circuit. S A clinical thermometer substantially as hereinbefore described with reference to the accompanying drawings. Dated this 29th day of March, 1995 CIBERVEU, S.A. By its Patent Attorneys DAVIES COLLISON CAVE 950329,p:\opcr\gcp,29465.92,7 ABSTRACT Clinical thermometer with digital and spoken display. The device comprises an input coming from a conditioning stage of signals given by a sensor, the latter consists of a negative temperature coefficient (NTC) resistor devised to be placed in contact with an area of the human body, a signal transducer consisting a resistance-capacity load network, a microcontrol- ler devised to receive information from the prior stages with- out needing an analog/digital conversion and having an output for a voice synthesizer that includes filters for eliminating spurious signals, and an amplifying stage of audible signals in view to the driving of an acoustic transducer, as a speaker, and a digital display of the measured temperature. The device also comprises the association in a unique integrated circuit of the stage conditioning the signals coming from the probe, the microcontroller and the stage conditioning the low frequency signals applied to the speaker, said integrated circuit including a voice synthesizer, a measuring circuit and a microcontroller sending out the appropriate signals to the ideal modules formed by the circuit. Appliable to the visual and sound displaying of the human body temperature.