FR2543712A1 - ACOUSTIC TRANSCEIVER FOR LOCATING OBJECTS - Google Patents

Abstract

THE INVENTION RELATES TO AN ACOUSTIC TRANSMITTER-RECEIVER. IT REFERS TO AN APPARATUS INCLUDING A 6AA INPUT TRANSDUCER, 7AA PROCESSING ELECTRONIC CIRCUIT AND 8AA OUTPUT TRANSDUCER THAT ARE POWERED BY A SUITABLE 5AA BATTERY. THE ELEMENTS, PLACED IN A MOLDED BOX, ARE CONTROLLED BY AN ACOUSTIC SIGNAL SUCH AS A HUMAN WHISTLE, SO THAT THE OUTPUT TRANSDUCER GIVES AN ACOUSTIC OR VISUAL SIGNAL. APPLICATION TO THE LOCATION OF OBJECTS THAT ARE NOT IN THEIR PLACE.

Description

The present invention relates essentially to

  aid for locating objects that are not discernible

immediately by sight.

  However, in other applications, the invention is intended for the identification of a control element

  or the like facilitating the operations of a person

peeled to maneuver this element.

  In an example of the first type mentioned above, we can cite the common case in which a person can not find a small object that she needs while she knows he is close but has been put to a bad location or that it is hidden by other objects and therefore can not be seen For example, a keychain may be in the pocket of a jacket that has been set aside or a glasses case may be find in a cluttered drawer of dresser It is boring and

  sometimes very long, to have to look for this object, and the invention

  In an example of the second type of application according to the invention, a machine comprising an emergency stop button which can be mixed with a large number of control buttons, must be able to be used.

  identified immediately by a novice operator of the machine.

  In all the cases indicated above, a common characteristic is that the person seeking the object or to identify any element is reduced to its own resources, so that any device that

  can help it be able to function without an artificial organ

extra sky.

  Thus, the invention relates to an acoustic transceiver intended to be attached to an object to be located or incorporated in such an object and which emits an output signal as a result of an audible triggering signal which can be produced by a person without mechanical assistance

or electric.

  Preferably, the acoustic transceiver is sensitive only to triggering signals within a predetermined narrow band of frequencies in the audio frequency range. In this case, the selected band is preferably such that a corresponding sound may be

  produced by a person, for example whistling.

  In the case of the location of hidden objects, the autonomous acoustic transceiver according to the invention emits an audible output signal and, preferably, this

  output signal is outside of the said predefined range

  terminated frequencies of the trigger signal so

  that an acoustic reaction is avoided in

  invention to the identification of elements or

  The output signal may be a visual signal from a lamp. In any case, the output signal preferably continues to be produced during a certain period of time.

  time after the cessation of the trigger signal.

  Thus, if it is assumed that an acoustic transceiver according to the invention has been attached to a key ring, when a person wishes to know if the keys are in his room, it is sufficient that it enters the room. room and whistle a short moment to get the answer, for example in the form of a "beep" indicating that the keys are present He may have to repeat this

  operation before finally locating the keys.

  In another case, when a person wishes to locate the lighting switch of a vehicle while

  at night, a short whistle causes a light to appear.

  near the lighting switch when it comprises a transceiver according to the invention, giving

such an output signal.

  Although it is preferable that

  receivers according to the invention are controlled by a sif-

  In addition, the invention also relates to transmitters

  receivers sensitive to acoustic signals in the range of audiofrequencies produced in other ways, for example

by a clapping of the hands.

  An embodiment of the invention may

  take a casing of cylindrical general shape, analogous

  to a cartridge, having an eyecup at a first

  the other end of the body can be closed by a removable cap,

  preferably screwed, intended to form a compartment of

  a battery or accumulator battery containing one or more battery cells or cells of low volume and high power, for example

mercury batteries.

  An input transducer such as a microphone

  electret is housed in the body and is intended for trans-

  forming the received sound into an electrical signal corresponding to an audio frequency, a circuit, preferably in the form of an integrated circuit chip, and an output transducer which can receive an electrical signal from the circuit

  and emitting an audiofrequency tone The two transduc-

  The input and output meters are preferably mounted near openings formed in the housing so that the passage of sound is facilitated. The circuit connects the input and output transducers as well as the element or elements of the amplifier. batteries or accumulators It may comprise, for example, a band-pass amplifier powered by the input transducer, in association with a filtering network intended to give an amplifier response bandwidth.

  included in the range of whistles by human beings.

  The output signal of the amplifier is transmitted to a detector circuit which itself controls an electronic switch in two positions, one in which the voltage of the supply element is applied to a capacitor so that charge and another in which the capacitor can discharge through the transducer

output, a vibrator in this case.

  Preferably, an on-off switch is also arranged so that the user can prevent the operation of the transceiver when it is not necessary, for example just before putting in the pocket a bunch of keys to which is hung transceiver A suitable type of on-off switch can be a rotary switch, controlled

  by a ring surrounding the body of the transceiver.

  Other features and advantages of the invention

  will be better understood by reading the description

  which will follow examples of embodiment and with reference to the accompanying drawings in which Figures 1 and 2 are longitudinal sections of an embodiment of autonomous acoustic transceiver according to the invention;

  Figure 3 is a cross-section of the

FIGS. 1 and 2;

  Figures 4, 5 and 6 are synoptic diagrams

  FIGS. 1 to 3 of an advantageous embodiment of the circuit of the apparatus of FIGS. and Figure 7 is a detailed diagram of the aforementioned circuit.

  The casing 1 AA of the device has a cylindrical shape

  drique and may have for example a length of 62 mm

and a diameter of 15 mm.

  A first end 2 AA of the cylinder has a frustoconical inclination shape equal to 180, comprising a mounting device for fastening a ring

split metal.

  The other end of the cylinder has a cap

  Removable 3 AA to give access to a rechargeable battery

emulators or batteries.

  The end cap 3 AA rotates at an angle of 400 and is provided with contacts to form a

  rotary switch by all or nothing.

  The casing 1 AA is preferably injection molded

  in a polycarbonate or a similar durable plastic manner. The electronic circuit 4 AA of the device is

  preferably formed from components available in the

  merce and it is housed just in front of AA batteries or batteries It consists of three parts, a 6 AA input transducer,

  an output transducer 7 AA, and an integrated circuit 8 AA.

  The input transducer may be formed of a

  miniature insert comprising a condenser microphone

  The purpose of this system is to detect the acoustic waves of a human whistle and to transform them into electrical energy. It is desirable that the highest sensitivity of the microphone is in the frequency band

between 660 and 1980 Hz.

  The response curve of the microphone should preferably

  decrease rapidly outside this band of

  so that the possibility of control of the device by unwanted signals is reduced, as well as

  the corresponding necessary processing of the signals.

  The output transducer 7 AA may be a miniature acoustic source of a known type, for example used in electronic cash registers and digital alarm clocks It gives a high output signal having a tone of 3.3 kHz, component

an acoustic alarm signal.

  The equipment needed to build the

  device has contacts for the power supply

  tation, switch contacts, and a fixing ring.

  The device has two contacts 9 AA for

the battery pack.

  A first contact is fixed in the removable end cap and may be formed of a strip

  coated metal (eg phosphor bronze).

  This contact also forms half of the contact

  of the switch, on the lip of the end cap 3 AA.

  The other contact of the battery pack is mounted in a wall 10 AA located midway inside the body of the housing. This contact can also be formed of a coated metal strip or a wire. steel

  coated with nickel, having the shape of a spiral spring.

  Two 11A switch contacts are intended to enable all-or-nothing control. One can be on the edge of the removable end cap

  and is part of the battery pack contact.

  The other 12 AA may have a coated wire disposed along

  the inner edge of the battery compartment

  and protrudes into cavities formed in the molded element. It protrudes from the outer edge of the cap into the compartment housing the electronic circuit and is shaped so that it is against the flat contact disposed in the endcap. all or nothing

  is obtained by rotation of the end cap 3 AA.

  The integrated circuit 8 AA is preferably a

  specialized monolithic circuit of very low power.

  The role of this circuit is to accept the electrical energy from the input transducer 6 AA, to process this information and to transmit to the output transducer 7 AA a tone signal giving an audible alarm following a signal The energy transmitted to the circuit may be from two or four 1.5 V silver oxide Ag 2 O cells, commonly known as type 576 and used

  in photographic equipment and calculators.

  The preferred embodiment of integrated circuit 8 AA may be connected in one of two ways as shown in FIGS. 4 and 5. FIG.

  a block diagram of this integrated circuit.

  In FIGS. 4 and 5, a power supply connected between terminals 1 and 2 is necessary for the circuit to operate. The positive end of the power supply must be connected to terminal 1 and the negative end to the

  terminal 2 The power supply may consist of batteries or accumula-

  emateurs or may be a voltage from a source placed at a distance and preferably between 2.4 and 7.0 V The current consumed under these conditions must be less than 50 p A. The frequency control circuit has a resistance and a capacitor mounted between the terminals

  3 and 4, and is common to both assemblies of the integrated circuit.

  This circuit or network must be stable so that it ensures

  reliable operation of the integrated circuit.

  The input transducer 6 AA shown on

  FIG. 4 is mounted between terminals 5 and 2 and the trans-

  Output conductor 7 AA is mounted between terminals 6 and 7.

  As shown in Figure 5, the input and output transducers 6 AA and 7 AA can be formed by a single device In this case, the optimal transducer

  having both functions is a piezoelectric disk.

  Referring now to Figure 6 on which

  the power supply is intended to distribute the voltage applied

  and to ensure his return.

  integrated does not have internal regulation.

  The operation of the integrated circuit depends essentially on the frequency of the oscillator and consequently on the output signal of the two dividing circuits

of the oscillator signal.

  The output signal of the microphone 5 is amplified at 8 and a pulse is created for each positive transition of the microphone voltage with a signal of

output of the oscillator 9.

  The period of the received signal is analyzed by

  the number of clock pulses of the oscillator between

  the impulses of the amplifier and of a conformal circuit

  The content of the period analysis circuit 10 can be loaded into a period register 11 and the equality of the two values can be checked by a controller.

12 period comparator.

  When the output time divider circuit 13 has counted to a predetermined maximum value and when the input signal is outside certain limits, the control logic circuit 14 goes into the idle state.

  in which the output signal is not transmitted and the

  When the output signal of the amplifier and the pulse shaping circuit 8 is active, the control logic circuit checks the number in the period analysis circuit and, when finds between the limits, for the first time after the inactive state, the content is loaded in the period register This is the transition state

  between the inactive state and the transmission state of a

  The duration of the transition state is determined by the contents of the tone transmission counter.

  For each successive signal of the amplifying circuit

  8, the period measured by the analysis circuit is checked with respect to the contents of the period register 11. If the values are equal for 64 consecutive periods, as measured by the counter 15, the circuit

  integrated goes to the tone transmission state.

  When the input signal is out of bounds during the transition state, the circuit returns to the inactive state The transition state starts again when the contents of the period register 11 and the circuit

  period analysis are not equal.

  During the duration of the tone transmission state, the output signal of the amplifier and the shaper circuit is suppressed. The tone divider circuit 16 can operate in the transmission state.

  tone, as well as the output buffer circuit 17.

  The latter is controlled by an output signal of the circuit

  divider 13 so that it forms several bursts of tone.

  The duration of the tone transmission state is determined by the divider circuit 13 which, when the terminal number is reached, resets the circuit to the inactive state ç Like the period register 11 and the comparator 12

  have a resolution of two bits, -four values are pos-

  Given the uncertainty in the digitization of the period of a received waveform, the circuit can

to be sensitive in four bands.

  When the oscillator is set to 52.2 kHz, the circuit has the following characteristics: Band input response one 825 to 942.9 Hz two band 942.9 to 1100 Hz three band 1100 to 1320 Hz four band 1320 at 1650 Hz Minimum duration at 825 Hz 77.6 ms at 1650 Hz 38.8 ms Output tone: 3.3 k Hz Output signal duration: 1.24 s Any modification of oscillator 9 causes

  a modification of the aforementioned operating parameters.

  Referring now to FIG. 7, which indicates that the three sections of the circuit A 2 form an oscillator operating at 52.8 kHz, corresponding to a period of 18.94 ps. The two sections of the circuit A 3 form a counter. cascade providing a division by four, having an output at the pin A 3 P 13 at 13.2 k Hz, corresponding to a

period of 75.76 ps.

  The output signal of the microphone is amplified

  by the circuits A 41 and A 13 which have a gain of 47 each.

  The bandwidth of this pair of amplifiers is

  limited in the low frequencies by the three conden-

  The three sections of circuit A form a Schmitt flip-flop, providing complete logic oscillation for the small microphone input signals. sections of the circuit A 16 which form, with a part of the circuit A 19, a pulse shaping circuit are such that they create, at the output A 16 P 13, a pulse formed with a positive duration corresponding to the signal of the A 16 P 11 spindle oscillator, the repetition frequency being equal to that of the A 16 P 3 pin signal from the output

microphone.

  The output signal of the oscillator at pin A 3 P 13 is transmitted to the period analysis circuit which is a four-stage cascaded counter having an overflow stage. The clock input signals arrive at pins A 4 P 3, A 4 P 11, A 5 P 3, A 5 Pil and A 6 P 3 and all share a common establishment signal transmitted by the output of the amplifier circuit and pulse shaper, after delay in both sections of circuit A 17 When the

  period between the common impulses of

  When applied to the period analysis circuit is between 8 and 16 pulses of the oscillator at pin A 3 P 13, the pins A 5 P 13 and A 6 P 2 transmit a low level signal. This occurs when the signal The pins P1 to P6 of the circuit A 6 form the overflow stage and, after receiving a clock signal, the pin A 6 P 2 goes to a high level until it is put to a low

  level at the end of the measurement time.

  The inactive state corresponds to the moment when the pin A 18 Pl is at a low level, ensuring the restoration of the transmission state switch (pins P 9 to P 13 of the circuit A 18) When the signal of the pin A 8 P 6 goes to a high level, indicating that the microphone receives a signal between 825 and 1650 Hz, the pin signal A 18 P1 goes high and loads the three least significant bits of the period analysis circuit into the period register Only the two most significant bits (pins A 7 P 5 and A 7 P 9) are active when the first stage (pin P 9 to P 13 of circuit A 6) and its

  comparator output at pin A 9 P 3 are not connected.

The period comparator -

  is realized with two exclusive OR gates and the pins P 10 to P 13 of the circuit A 8 During the state of transmission, the pin A 18 P 10 is at a low level and the pin A 18 P 12 at a low level as long as the period comparator indicates

  that the entry period and the memorized period are identi-

  within the limits of the resolving power of the circuit.

  When the microphone output signal is outside the 825 and 1650 Hz limits during the transition state, the pin A 8 P 6 signal goes low and sets the control logic to inactive The two sections of the circuits A 31, A 32 and A 33 form a six-stage cascaded counter which constitutes the tone presence counter. This counter chain is set to zero each time the output signal of the period comparator. at pin A 18 P 1 O goes to a low level indicating that the number memorized

  and the current number are not equal.

  When the current tone counter reaches a number equal to sixty-four, pin A 20 P 3 receives

  a clock signal and the circuit passes to the transmission state.

  The output signal of the amplifier is inhibited by the signal of the pin A 2 O P reaching the pins P 3 and PS of the circuit A. The signal of the pin A 20 P 2 is weak during the state of the signal. tone transmission and the oscillator signal from pin A 3 P 13 is transmitted by pin A 19 P 6 to pin A 34 P 3 The tone divider circuit controls the output buzzer (circuit A 10) and the output time divider circuit,

  using the signal from pin A 34 P 13.

  The output buffer corresponding to the pins P 6 and P 10 of the circuit A 10, is set in three states by the pins P 1 and P 2 of the circuit 20 during the inactive state so that only one transducer can be used as a microphone and loudspeaker The output buzzer is also controlled by a flip-flop of the output time division circuit so that it gives eight tone bursts

  during the output signal of 1.24 s.

  The output time divider circuit is a twelve-stage cascaded counter which has 4096 cycles of the output signal at 3.3 kHz and then transmits a clock signal to pin A 20 P 11 A pulse of pin A 20 P 13 restores the pin P 4 of the circuit A 20 and interrupts the state of transmission of tone, the circuit returning

in the idle state.

  It should be noted that the invention, at least in the embodiment described above; relates to a new, original and extremely useful device for locating objects that are not in their place Of course, various modifications may be made by those skilled in the art devices that have just been described only as non-limiting examples without

depart from the scope of the invention.

Claims (10)

  1 Acoustic transceiver intended to be fixed or incorporated in an object to be located, characterized in that it transmits an output signal following an acoustic triggering signal, this signal being able to be produced   by a person without mechanical or electrical assistance.   2 Transceiver according to claim   1, characterized in that the acoustic triggering signal   is within a predetermined range of frequency   higher than the normal range of voice frequencies.   3 Transceiver according to claim   2, characterized in that the acoustic triggering signal   is formed by a whistling of a person.   4 Transceiver according to one of the claims   2 and 3, characterized in that the output signal is an audible output signal which is outside   the predetermined range of frequencies of the trigger signal   so that an acoustic reaction is avoided.   Transceiver according to one of Claims 1 and 2, characterized in that the output signal   is a visual signal given by a lamp.   6 Transceiver according to any one of   of the preceding claims, characterized in that the   output signal stays for a while   after the end of the trigger signal.   7 Transceiver according to any one of   of the preceding claims, characterized in that   comprises an input transducer (6 AA) for receiving the trigger signal and transforming it into a first electrical signal, a circuit (8 AA) for processing the first electrical signal, and an output transducer (7 AA) intended to emit the output signal after reception   a second electrical signal from the 5 circuit (8 AA).   8 Transceiver according to claim 7, characterized   in that the input and output transducers (6 AA, 7 AA) are both formed by a single device such as a piezoelectric disk.   9 Transceiver according to one of the claims   7 and 8, characterized in that the circuit (8 AA) comprises   a band-pass amplifier (8) fed by the transducer   input filter (6 AA) in association with a filter network for providing an output response bandwidth when it is controlled by the trigger signal in a predetermined range, and the response is transmitted to   a detector circuit (16) which controls an electronic switch   apparatus for forming an output signal by an oscillator (9) and an output buffer (17),   thanks to the output transducer (7 AA).   10.Transceiver according to one of the claims   7 and 8, characterized in that the circuit is a pellet integrated circuit (8 AA).   11 transceiver according to claim, characterized in that the circuit (8 AA) is a circuit   monolithic specialized very low power.