Note: Descriptions are shown in the official language in which they were submitted.
2~37~
This InYention relates to a clinlcal thermometer wlth dl-
gltal and spoken dlsplay.
Cllnlcal thermometers are known in the present state of
the art, that Incorporate a dlsplay for the measured tempera-
ture values, Indlcatlng the sald values by means of flgures,
sometlmes along wlth other Indicatlons. In some cases, the
known models show leglbllity problems, speclally at a certaln
dlstance and to people wlth slght problems, and thls Is speclal-
ly true whenever LCD dlsplays are used.
The temperature gauge to be hereln disclosod Is further
characterlsed In that It is able to send out Intelllglble sounds
correspondlng to the words that indicate the temperature values,
so that slghtless people and other people wlth slght deflclency
could use the thermometer with no need to read the values, but
by only hearlng perceptlon of the sald values. To thls end, the
electronlc clrcult of this new cllnlcal thermometer Includes a
volce synthetizer that, at the same tlme the dlsplay shows fl-
gures correspondlng to the thermal values measured, sends out
sound slgnals whlch as a whole form words, also Indlcatlng the
values measured by the device.
In the present patent the structure of a clrcult
Is descrlbed on whlch the measuring devlce for the human body
temperature ls based, sald clrcult belny connected, on the one
hand, to a probe devlsed to be placed In contact wlth the human
body, and on the other hand, to a speaker devlsed to provlde
slgnals correspondlng to the temperature values, as well as a
dlsplay deslgned to exhibit signs correspondlng to the sald va-
lues.
The proper clrcuit, represented In the block dlagram ac-
companylng the description of the patent, functlonally Includes
~,.
~1 ~37~
a conditionlng stage of the lnput signals, a mlcrocontroller and
a conditionlng stage of voice slgnals applled to the speaker.
Said circuit can be embodied ln several ways, one of them
conslstlng of an assembly of discrete components dyly bullt up,
though, accordlng to the current physlcal constltution of elec-
tronlc circults, the integrated constructlon of sald components
Is preferred, In whlch the components carry out the loglc func-
tlons orlglnatlng the operatlon of the devlce.
For better understandlng of the above descriptlon, a draw-
lng is attached In whlch a practical case of embodlment of the
Invention is shown, schematically and only as a non llmltlng
example.
The drawing is a block diagram In which the stages deslgna-
ted with numerals correspond to the following parts of the clr-
cuit.
Block 1 conslsts of a thermal probe, that Is, a devlce sen-
sltive to the temperature level and fluctuatlons, providing
an electrlcally measurable signal which Is proportlonal to
the applied temperature. The probe Includes a NTC or negatlve
temperature coefflcient resistor, characterlsed In that its
ohmic ~alue decreases as the applled temperature decreases.
The system operates accord~ng to usage tables supplled by the
manufacturer, so that the resistance-temperature ratlo Is sim-
ple and fast.
~ lock 2 carrles out the conditionlng of slgnals produ-
ced by the thermal probe and translates the value of the NTC
resistor Into data dlrectly processable by a mlcroprocessor
or a mlcrocontroller bullt in the devlce. This circult Is ba-
sed on a reslstance-capaclty loading network formed by a pre-
cislon reslstor, the NTC reslstor and a capacltor.
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3 21~379~ 1
This way the temperature Is directly measured from the
microcontroller, wlth no need to ~nclude an analog/dlgltal
converter In the device deslgn. In add~tlon, due to the me- !
thod used, errors or~glnat~ng from the voltage drop of the
batterles and by the condltlon of the ca~acltor are elImlna-
ted.
Block 3 makes up the mlcrocontroller for the whole sys-
tem, by means of wh~ch the temperature Is measured, Informa-
tlon Is supplled to a set of quartz crystals bullt In the
devlce, and data necessary to the volce synthetlzer are also
provlded. The m~crocontroller ~s custom made and Is based on
a flnite state machlne, duly programmed to carry out the ge-
neral operatlon algor~thm of the thermometer and the communi-
catlon with the several external modules (synthetlzèr, quartz
crystals and NTC reslstor.
Due to the technology used, synthesls module and liquld
crystal 1nterface modllle are physlcally Integrated wlth the
mlcrocontroller, sald technology being des1gnated ASIC.
Block 4 ensures the conditloning of analog volce slgn-
als, Includlng the fllterlng and ampllflcatlon of the sald
slgnals. The module formlng thls stage Is Integrated Into the
above mentloned component.
Sald stage 4 comprlses, In accordance wlth the above
mentloned, a set of fllters to ellmlnate spurlous slgnals
that may have been reproduced In prior stages and Includes
volce synthetlzatlon, the signals of whlch, belng of llttle
amplltude, are magnlfled by an ampllfler butlt In the same
stage, provldlng the apropriate amplltude for drlvlng the
speaker formlng stage 5. The latter, In a preferred embodl-
ment, wlll be bullt In the thermometer houslng.
- 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 max-
imum and minimum values, and other information.
Amldst the funct~onal parts formlng the cl~nlcal thermo-
meter dlsclosed In the orlginal patent, three parts are Invar-
lable and ~nd~spensable the probe for the immedlate senslng
of the thermal level of the human body, wh~ch Is the magnltude
to be measured; the speaker for the send~ng out of sound slgn-
nals lndlcatlng the measured values, and the dlsplay for the
vlsual exhlbltlon of the values. These parts, therefore, ~111
not be the subject of further conslderations.
Functlonal parts definlng the essentlallty of the clr-
cult formlng the cllnlcal thermometer accordlng to the orlgln-
al patent constitute the subject matter of thls Patent,
whlch contemplates the practlcal embodlment of the
above mentloned parts.
The matter Is, according to the appended clalms, to make
blocks 2, 3 and 4 of the diagram accompanying the descrlption
of the orlglnal patent ~n the form of a unlque equlvalent
block, formed by an Integrated clrcult of the type called ASIC
or speclflc for the foreseen appllcatlon. Sald clrcult carrles
out the functlons of the above mentloned blocks, with the ad-
vantage of slmpllflcatlon and slze and welght reductlon. ~he
cost of the lntegrated clrcult, even though thls Is made accord-
ing to the speclflcations of the thermometer manufacturer, Is
also slgnlflcantly reduced.
When analyslng the functional structure of the unlfled
block that now forms the forms the maln part of the thermometer
constitutlon, the followlng subassemblles may be clted, bearlng
in mind that dlstlnction is merely ~o1rQal~and just In order
to follow the input and output signals runnlng, respectlvely.
1. A voice synthe~i~er based In ADPCM technology of 3
bits, allowing to obtain an audible frequency range resultlng
in a voice quality which is sufficlent for the output stage.
Said syntheslzer Is based on a 12 Kbytes memory contalnlng
the voice to be synthesized and a machine of synchronous states
that directlons the memory and coord~nates the approprlate
messages to shape the signs to be displayed, wlthln a range of
values from 32.0 to 42.0 centigrad degrees.
2. A measurlng clrcult based on a machlne of synchronous
states that uses d~gital s~gnals to directly carry out the
measurement on the NTC reslstor assoclated to the probe. Thls
allows to el~mlnate an interface for the analog/dlgltal conver-
slon.
3. A mlcrocontroller, also based on a machlne o~ synchro-
nous states and servlng to send the approprlate slgnals to every
Ideal module of the clrcult, in order to carry out the algorlthm
or operatlon necessary for the case: startlng of the devlce,
measurement of the phys~cal magnitude, feedlng current applled
to the volce syntheslzer and to the s~gn dlsplay, as well as the
dlsconnectlon of the devlce.
lt is worthwhlle to point out that the measurement method
on the thermometer probe allows conslderlng the Input slgnal
condltloner as a mere software routlne, slnce there Is no module
devlsed to brlng about the analog/dlgltal converslon. The employ-
ed method uses dlrectly the signals avallable In the mlcrocon-
troller to carry out a frequency-temperature converslon. That
is, there does not exist physlcally an A/D converter module In
the Integrated clrcult that gathers the above mentloned functlon-
al stages.
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Temperature measurement is done by computlng the number
of charges and d~scharges effected by the NTC reslstor on a
capacltor and refer lng it to the number of charges and dis-
charges effected on a resistor of known value. From the result-
lng ratlo the NTC value Is obtalned, and this value corresponds,
accordlng to a prevlously established table, to the temperature
of the probe. Thls measurement method makes it posslble to s~m-
pllfy at maxlmum the related module, as well as to obtaln a
measurement value which is stable in relatlon to changes In the
feeding voltage ~supplied by a set of batterles Included In the
device houslng) and to differences In the ohmlc value toleran-
ces of the capacitor used.
A further advantage of the embodlment under descrlptlon
is the very small number of components dlrectly Involved with
the measurement: just a capacitor, a low tolerance reslstor and
the NTC reslstor assoclated to the probe.
In a preferred embodiment, the new temperature gauge
wlll comprlse a houslng showlng, In a easlly accesslble plac~,
the thermal probe arrangement, able to be applled to the hu-
man body, the housing ~ncluding as well the speaker compart-
ment and a set of openings for the output of the generated
sounds.
