WO2009074973A1

WO2009074973A1 - Arrangement and method for respiration detection and/or measurement

Info

Publication number: WO2009074973A1
Application number: PCT/IB2008/055277
Authority: WO
Inventors: József Vincze
Original assignee: Vincze Jozsef
Priority date: 2007-12-13
Filing date: 2008-12-12
Publication date: 2009-06-18
Also published as: EP2231014A1; HU0700807D0; HUP0700807A2

Abstract

An arrangement for the detection and/or measurement of respiration; comprising at least one holder (2) associated with at least one specific part of a living body (1); a sensor unit detecting parameter change provoked by the position change or movement of the living body (1) in direct relation to respiration, whereas the sensor unit is assigned to holder (2), and the sensor unit is connected to a control and processing unit; a signal sequence generator, the signal sequence generator is fixed on holder (2); a power supply powering the several stages and units of the arrangement; a carrier element which conducts the signal sequence generated by the signal sequence generator to the sensor unit, wherein the control and processing unit connected to the sensor unit is realised as a unit detecting and where appropriate measuring the change of propagation of the signal sequence over time.

Description

Description ARRANGEMENT AND METHOD FOR RESPIRATION

DETECTION AND/OR MEASUREMENT

Technical Field

[1] Present invention relates, on the one hand, to an arrangement for the detection and/or measurement of respiration; the arrangement comprises at least one holder associated with a specific part of a living body; a sensor unit detecting changes of one or more parameter provoked by the position change or movement of the body in direct relation to respiration; whereas the sensor unit is assigned to the holder and is connected to a control and processing unit, the sensor unit comprises signal sequence generating unit, whereas the signal series generating unit is fixed onto the holder and, moreover, a power supply unit supplying energy to the components and units of the arrangement. The invention relates, on the other hand, to a method for the detection and/or measurement of respiration, comprising the steps of detecting the position change or movement of the body in direct relation to respiration by monitoring change in at least one parameter associated with the position change or movement, and, in case of respiration measurement, recording the parameter change over time. Background Art

[2] The measurement of human respiration over time is generally effected at two distinct places. One consist of the measurement of the current of air in or near the nasal and oral cavity. The other method consists of the measurement of the change in position of the chest or the abdomen, that is, rise and fall due to breathing in and out. This invention concerns measurement at the latter place.

[3] The best-known methods for the measurement of the change of the chest and the abdomen over time (the recording of the respiratory curve) may be divided into two main groups.

[4] One measures body resistance, which depends to a minor extent on the quantity of air in the lungs. This method poses a special problem, namely that body resistance is small and, therefore, low-resistance electrode connections are needed. The advantage of resistance measurement is that only 2 to 4 electrodes must be stuck on the chest, whereas body circumference measurement requires two belts running around the body.

[5] The other measures the change in body circumference during respiration due to the rise of the ribs or the movement of the diaphragm. One conductive fibre or several resistance strain gauges are attached to the body, the resistance of which changes under the effect of stretching. It is a special problem with this measurement technique that it is not sufficient to do the measurement at one place, since the circumference of the abdomen changes somewhat in case of chest respiration, and that of the chest in case of abdominal respiration. Body circumference measurement has the advantage that no electric connection is needed with the body.

[6] It is a problem with both methods that the effect is on a very small scale; it is commensurable with the noise signals. The respiration detector according to the invention is based on body circumference measurement, but its method differs from the above.

[7] GB 2743 describes a simple, mechanical solution for measuring the change in body circumference during respiration, which resembles most the use of a measuring tape: a belt is fastened onto the chest of the person being examined, which adapts relatively freely to the change of the chest of the examinee during respiration, whereas the belt is provided with a scale, the reading of which allows to detect and establish volumetric change. It follows from the nature of this solution that it is rather inaccurate, and it is decisively adequate for detection, unless the belt slips down the chest of the examinee during respiration.

[8] US 4,602,643 describes a pneumatic breathing sensor device which contains a belt- like apparatus, the air-filled internal chamber of which is in connection with the atmosphere. During respiration, under the effect of the change in chest volume, the wall of the chamber is flexibly compressed, and hence the volume of the chamber changes in proportion to with the extent of the respiration, and the air inside communicates between the chamber and the external space so that air flows out from the chamber of the belt upon inhaling and air flows into the belt upon exhaling, and the visible movement of the detector component, a ball, placed in the way of the airflow, indicates respiration, but the device may also be attached to a monitoring equipment, which will emit an alarm signal should the respiration fall under a predefined level or stop. This simple, disposable, device has been developed primarily for monitoring the respiration of infants, and it is not suitable for detecting or measuring the measure of respiration.

[9] The second document indicated above represents transition from the purely mechanical measuring methods to the field of electro-mechanical measuring transducers. DE 10316255 also proposes to place a belt-like holder on the chest of the person being examined, so that the ends of the belt may move relative to one another as the chest rises and falls, and that mechanical change is used to turn a potentiometer, and the signal so received is processed by the electric/electronic unit which contains the potentiometer itself. One of the shortcomings of this solution is that forces, frictions occurring during electro-mechanical conversion may affect the measurement in an uncontrollable and unrepeatable manner, the transducer - the potentiometer - being used is susceptible to abrasion, contact fault, and its replacement necessitates the re- calibration of the entire apparatus, due to the different potentiometer characteristics.

[10] US 2005/0171417 describes a respiratory detection and measurement system, in which the person being examined lies on the examining table, and a sensor unit designed as a cord and fixedly attached to the table at one end is being pulled across his chest, while the other end of the cord is attached to a linear position encoder capable of determining mechanical displacement. As the chest of the person rises or falls during respiration, the cord disposed across it will also stretch and slacken, and the linear position encoder will detect its movement. One of the drawbacks of this solution is that the examinee must lie on the examination table and, on the other hand, if that person slides a little up or down the table, his chest size will change, and the measuring apparatus may mistakenly evaluate that as breathing or a change in the measure of breathing.

[11] US 5,195,528 describes an acoustic respiration detector, wherein two microphones are placed in the face mask to be put on the examinee's head in case of respiration examination, and the microphones receive the sounds of inhaling and exhaling, and the signals of the microphones are used to determine the time span of exhaling and inhaling. One of the - not always acceptable - characteristics of this solution is that the person to be subjected to the respiration examination must wear a special mask, as well as detecting and measuring units connected to it; on the other hand, despite the mandatory signal processing operations, the signal provided by the microphones applied as sensor units does not provide measurement data repeatable with the same results. A further disadvantage is that the solution is suitable primarily for detecting the length of the breathing periods and allows determining the breathing intensity at a signalling level only.

[12] EP 1731094 proposes a garment, a shirt, which contains a belt-like respiration measurement apparatus in the range of the chest and abdomen, respectively, of the examinee. The apparatus in the garment collecting and providing biological information on the examinee contains woven sensors of variable conductivity emitting analogous signals in the shirt, of varying tightness during breathing, in correlation with the respiration. It is a shortcoming of this solution that the sensors being applied will perceive and transmit any displacement causing size change or stretching as change due to respiration and, consequently, if the examinee performs more intensive movement, the apparatus can only be used for the detection, not the measurement of breathing, and event that with limited reliability.

[13] EP 1374767 proposes a respiratory measurement apparatus in which a belt- like holding unit contains a closed chamber filled with air and touching the body, that is, the chest and/or the abdomen. During respiration, the movement of the chest or abdomen of the examinee causes a change in volume in the chamber, and it is this change in volume that is measured and evaluated during respiration assessment. It is a deficiency of the solution that, in order to attain the desired effect, the belt must be fastened tightly onto a part of the body of the examinee, which exerts such force on the given body part as may falsify the measurement results if the body part in contact with the chamber reacts by smaller or weaker movement than usual under the effect of the force bearing on it.

[14] WO 2006/008745 proposes an apparatus for breathing pattern determination whereas a headset with microphones is put on the head of the examinee. Sounds generated or emitted during breathing are monitored by a microphone placed in front of the mouth of the person, and the microphone signal is used for further processing, while the headset is used to relay instructions to the examinee, so that he should know exactly what to do during the examination. The solution does not provide repeatable, precise results due to detection by the acoustically open microphone and, of course, specific ambient conditions must be met in this case, too, to be able to perform the examination, which cannot be done in a noisy environment.

[15] WO 2007/069111 describes a device for assessing the physical condition of a person, said device comprising an apparatus for respiration measurement. The apparatus contains a holding belt to be fastened on the examinee, with a signal emitting and a signal receiving sensor unit at its two ends, so that the relative displacement of the ends of the belt during respiration implies the relative displacement of the emitter and the receiver elements as well, as a result of which the signal received by the sensor unit, to be processed during measurement later on, will also change. The document proposes an optical light source e.g. a LED as a signal emitter and a photodiode or photo- transistor as a sensor unit eventually fixed relative to one another, and an intermediate light-blocking element is moving during the breathing of the examinee. The movement of the light-blocking element provokes a change in the quantity of received light, and hence the measure of the displacement may be detected in a relatively more accurate manner by the sensor unit, and the design of the light-blocking element may play an essential role in that. Furthermore, this solution considers it feasible also to have an emitter and a receiver unit in electromagnetic connection, whereas the change in the relative distance of the emitter and receiver units, or the movement of the magnetic light-blocking element (shunt) put in between the two units, will cause a signal change at the output of the sensor unit through the change in the magnetic coupling.

[16] It is a drawback of this solution that it must be forcefully and perfectly shielded against the external environmental effects and, on the other hand, the measurement range of the apparatus can only be adjusted in a narrower range, and its accuracy depends of the stable positioning of the units being used and the fixing and shape of the optical or magnetic shielding element, which can only be adjusted in a complicated way, if at all, in a given apparatus. Disclosure of Invention Technical Problem

[17] An object of the present invention is to create an arrangement and method for the detection and/or measurement of respiration which is universally applicable for various bodies and requires minimum or no co-operation on the part of the examinee. A further object is that the arrangement, when in use, should imply no limits for the person concerned and that it should cause no inconvenience in terms of movement or everyday behaviour. Another objective is that the arrangement should contain no element to be fastened directly on the skin. Yet anther objective of the invention is that the measuring limit and the measurement accuracy of the arrangement should be alterable and adjustable relatively easily, simply and quickly. In addition, it is our objective that the solution should allow to detect and/or measure respiration in a simple and cheap way. Technical Solution

[18] It has been realised that, as compared to the known solutions and proposals, the change in body circumference related to respiration may be determined in a manner that resembles most measurement by the traditional tape measure (centimetre), but the old mechanical method must be realised by a new measuring medium which has an adjustable scale and is not disturbed by the ambient conditions. We have realised that periodic signal sequence, e.g. sound waves, are most expedient for this purpose, because under the effect of the change in respiration over time, the distance between the signal source and the signal receiver will change over time. And if the distance between the signal source and the signal receiver changes, then the phase change will be proportional to the displacement. Hence, by measuring the phase change over time between the signal source and the signal receiver, we shall obtain a signal which is proportional with the length of the distance covered by the signal, i.e. with the intensity of respiration.

[19] To solve the problems as describe above, an arrangement for respiration detection and/or measurement has been developed, comprising at least one holder associated with at least one specific part of a living body; a sensor unit detecting parameter change provoked by the position change or movement of the living body in direct relation to respiration, whereas the sensor unit is assigned to holder, and the sensor unit is connected to a control and processing unit; a signal sequence generator, the signal sequence generator is fixed on holder; and a power supply powering the several stages and units of the arrangement; the arrangement comprises a carrier element which conducts the signal sequence generated by the signal sequence generator to the sensor unit, and the control and processing unit connected to the sensor unit is realised as a unit detecting the change of propagation of the signal sequence over time and, where appropriate, measuring the change of propagation of the signal sequence over time. [20] According to a preferred embodiment of the arrangement the holder associated with a specific part of the living body is a holder placed around the chest. [21] According to another preferred embodiment of the arrangement the holder associated with a specific part of the living body is a holder placed around the abdomen. [22] According to another preferred embodiment of the arrangement the holder associated with a specific part of the living body are holders placed around the abdomen and the chest.

[23] In a preferred embodiment the holder is realised as a belt.

[24] According to another preferred embodiment of the arrangement the belt constituting holder is adjustable so as to fit bodies of various sizes. [25] According to another preferred embodiment of the arrangement the belt is made of an elastic material.

[26] In a preferred embodiment the belt is realised as a rubberised strap.

[27] According to another preferred embodiment of the arrangement the belt comprises a rubberised strap inset. [28] According to another preferred embodiment of the arrangement co-operating Velcro fastener segments are fixed at the end sections of an open-type belt. [29] According to another preferred embodiment of the arrangement the belt is associated with a shoulder strap. [30] According to another preferred embodiment of the arrangement the sensor unit contains at least one microphone. [31] According to another preferred embodiment of the arrangement the signal sequence generator consists of an acoustic signal generator and a sound emitting device connected to it. [32] According to another preferred embodiment of the arrangement the acoustic signal generator is an audio frequency signal generator. [33] In a preferred embodiment the audio frequency signal generator is a sine wave generator.

[34] In an another preferred embodiment the sine wave generator is quartz-controlled.

[35] According to another preferred embodiment of the arrangement the carrier element conducting the signal sequence to the microphone of the sensor unit is a tube made of elastic material.

[36] The tube is preferably a silicone tube.

[37] According to another preferred embodiment of the arrangement the sound emitting device is a piezoacoustic emitter. [38] According to another preferred embodiment of the arrangement the signal sequence generator is fixed on the holder in an adjustable position.

[39] According to another preferred embodiment of the arrangement the microphone is fixed on the holder in adjustable position.

[40] According to another preferred embodiment of the arrangement the control and processing unit comprises an input amplifier, a filter connected to the output of the input amplifier, a comparator connected to the output of the filter and a processor constituting a unit measuring the difference in time, one input of the processor is connected to the output of the comparator and a second input of the processor is connected to the output of the sine wave generator of the signal sequence generator, and a measurement data logger is connected to an output of the processor.

[41] In an also preferred embodiment the measurement data logger comprises replaceable semiconductor storage means.

[42] In a further preferred embodiment the replaceable semiconductor storage means is a memory card or a pen-drive.

[43] According to another preferred embodiment of the arrangement the power supply consists of battery cells arranged in a battery holder or the power supply is a rechargeable battery.

[44] According to another preferred embodiment of the arrangement the power supply is removably fastened on holder unit.

[45] In an another aspect the task set has been solved by a method for respiration detection and/or measurement, comprising the steps of detecting the position change or movement of a living body occurring in direct relation to respiration, by monitoring change in at least one parameter associated with the position change or movement, and in case of respiration measurement, recording the parameter change over time; and detecting, as a parameter associated with the position change or movement, a change of propagation over time of an acoustic signal sequence conducted along the body part involved in respiration.

[46] According to a preferred realisation the method comprises emitting an audio frequency signal as the acoustic signal sequence.

[47] According to another preferred realisation the method comprises emitting a sine wave signal as the audio frequency signal.

[48] According to another preferred realisation the method comprises detecting, as a change over time of the propagation of the acoustic signal sequence, the change of the phase difference between the emitted signal sequence and the signal sequence reaching the sensor unit on a longer distance due to respiration.

[49] According to another preferred realisation the method comprises detecting the phase differences by zero crossing detection.

[50] According to another preferred realisation the method comprises influencing the accuracy of the measurement by the chosen frequency of the acoustic signal sequence. Description of Drawings

[51] A better understanding of the present invention can be obtained from the following detailed description in conjunction with the drawings, in which

[52] Figure 1 is a schematic view of a possible application of the arrangement according to the invention,

[53] Figure 2. shows a block diagram of the electric circuit of a possible embodiment of the arrangement according to present invention,

[54] Figure 3 shows a more detailed circuit diagram of another possible embodiment of the arrangement according to the invention, and

[55] Figure 4 shows the structure of a possible holder of the proposed arrangement.

Best Mode

[56] Figure 1 shows a possible and customary application of the arrangement according to the invention. Holders 2 designed as belts are placed on body 1, more specifically on the chest and on the abdomen, of an examinee, so that said 2 holders and the units carried by them should influence the movement and general disposition of the person concerned hardly or not at all. In addition to holders 2, further sensors are visible on the examinee, namely motion sensors 3, preferably piezoelectric motion sensors 3, the structure and operation of which is known to those skilled in the art from prior art, are placed on the tight and ankle of the person, which are meant to indicate the movement, hence the wakefulness or occasional sleep, of the examinee.

[57] Figure 2 shows the block diagram of a possible embodiment of the proposed respiratory measurement arrangement. In the represented solution, the arrangement contains two main units: unit 4 is mounted on holder 2, solidly fastened to the latter, whereas in the given embodiment, unit 5 is connected to unit 4 by wire and serves the processing and measurement of the detected signals. Unit 4 contains a piezoacoustic sound emitting device 6, a microphone 7, and a tube 8 interconnecting them acoustically. Unit 5 contains a clock pulse generator 51, a sine wave generator 52 and a processor 53 connected to its output, and storage means 54 connected to the processor 53 in the customary way and, furthermore, an amplifier 55, a filter 56 attached to its output, zero crossing detector 57 attached to its output, the output of which is connected to the processor 53. One of the outputs of sine wave generator 52 is also connected to the processor 53, whereas its other output is connected to piezoacoustic sound emitting device 6 of the sensor unit 4. Power supply 58 providing the electric components and units with energy is regarded as part of control and processing unit 5, but it may, of course, be realised also separately from control and processing unit 5, in which case it is connected to control and processing unit 5 by wire, in a manner known in the art. It should be noted that whereas sub-units of sensor unit 4 are acoustically connected, sub-units of control and processing unit 5 are connected electrically to one another and to the relevant sub-units of unit 4.

[58] In the present embodiment, sine wave generator 52 and piezoacoustic sound emitting device 6 constitute the signal sequence generator of the arrangement.

[59] The principle of detection, as realised by the aid of the embodiment designed as described above, which can be regarded as an exemplary embodiment of the method according to the invention, is that sound waves are conducted with the help of the elastic tube 8 around the living body 1. Tube 8 is placed in holder 2 designed as a belt, and the latter is fastened onto the chest and/or abdomen of the examinee. Of course, detection and measurement may be realised by a single holder 2, to be placed either on the chest or on the abdomen, but more comprehensive detection and measurement requires the placement of two holding units 2 on the said body parts. An acoustic source, in the given case piezoacoustic sound emitting device 6, is placed at one end of tube 8, and a signal receiver, in the given case microphone 7, is placed at its other end. Piezoacoustic sound emitting device 6 and microphone 7 may be fastened on the respective ends of tube 8 so that tube 8 should form an acoustically closed chamber together with the said elements. The frequency of the emitted acoustic signal does not influence the essence of the measurement, but it has been established on the basis of our examinations that the acoustic conductivity of tube 8 is more favourable in the range of audible frequencies. A comparison of the signal, in the given case a sine wave signal, originating from the piezoacoustic sound emitting device 6, with the signal detected by microphone 7 at the end of tube 8, shows that, given the speed of sound, the signal of microphone 7 is delayed relative to that of piezoacoustic sound emitting device 6. The delay may amount to several periods depending on the wavelength and distance of the acoustic signal.

[60] Under the effect of the change of respiration over time, the distance between the acoustic signal generator and receiver components placed at the two ends of tube 8 will also change over time. If that distance is not an exact multiple of the wavelength being used, the signal of microphone 7 will not be in phase with the signal of piezoacoustic sound emitting device 6. Where the distance between piezoacoustic sound emitting device 6 and microphone 7 is altered, the phase change (within one wavelength) will be proportional with the displacement. By measuring the change of the phase between piezoacoustic sound emitting device 6 and microphone 7 over time, we shall obtain a signal which is proportional with the intensity of the breathing.

[61] In the example presented here, sine wave generator 52 produces a signal of frequency of 3.6 kHz, radiated to tube 8 by piezoacoustic sound emitting device 6. Tube 8 may be any tube made of an elastic material; in the tests and experiments, common silicone tube proved to be the most adequate for this purpose. Piezoacoustic sound emitting device 6 radiates one signal of around 40 dB/100 mm, received by microphone 7. An electret or condenser microphone with a sensitivity of -62 dB is applied as microphone 7. The signal of microphone 7 is amplified approximately 850-fold in amplifier 55 then it is led to filter 56, where 3.6 kHz band filtering is applied on it. The amplified and filtered signal will be transmitted to zero crossing detector 57, at the output of which a rectangular signal suitable already for processing appears. The use of the rectangular signal is advantageous because the zero-point transition of the signal can be easily detected. The time differential between the rectangular signal exiting the zero crossing detector 57 and the synchronising signal obtainable at one of the outputs of sine wave generator 52 is measured by processor 53. It has proved to be expedient to select the sampling frequency at 10 Hz, when measurement by processor 53 is done every 0.1 second, with a resolution of 9 bits in each of the channels. The differential of the consecutive values measured at the output of processor 53 is represented with a resolution of 1-1 byte each. The measurement values are stored in storage means 54. Under the above conditions, tube 8 may undergo a measurable stretching of maximum approximately 200 mm/s but such a value will not occur in case of normal respiration. With the applied parameter setting, the widest range which may be represented in one byte covers values from -128 to +127.

[62] In a preferred embodiment, sine wave generator 52 is quartz-controlled, which provides, in the manner familiar to those skilled in the art, high stability to the signal sequence radiated by piezoacoustic sound emitting device 6.

[63] In another embodiment, also a preferred one under certain circumstances, tube 8 is

Y-shaped, with piezoacoustic sound emitting device 6 located in its common leg and one microphone 7 secured in each of its two upper branches. In this case, the signal recorded by the microphones 7 is received and processed alternately, so that the voltage of microphones 7 is switched on and off by processor 53 (not shown in the drawing), and the channel to be measured, alternately one or the other, is also selected by processor 53.

[64] Figure 3 shows the circuit diagram of the arrangement according to Figure 2 in more detail. Since the individual functional units are easy to identify for those skilled in the art, the units of Figure 2 are indicated in dotted line in the Figure. Owing to expedient and targeted high-level integration, one circuit unit may perform several functions or may contribute to the performance of several functions (in the case described here, cf. clock pulse generator 51 and processor 53), depending on the specific design ever, is considered as a routine activity on the basis of the description for a person skilled in the art. Of course, as it will be evident for those skilled in the art, joint placement of units 4 and 5 within one housing is also possible. [65] Circuit U7 of power supply 58 produces a stabilised voltage of 3.6 V from the voltage of approximately 4.8 V of the used one-way batteries or rechargeable accumulators. Circuit U5A produces operating-point voltage for operation amplifiers U5B, U6A and U6B.

[66] Operation amplifiers U5B, U6A and U6B of amplifier 55 and filter 56 amplify the signal of microphones 7. The aggregated gain of the amplifiers is around 850-fold at 3.6 kHz. The value of amplification is frequency-dependent; the value is approximately 1 at 360 Hz and 36 kHz. (The signal outputted by microphone 7 is around 2.5 mV.) Storage means 54 is realised by circuit Ul. Note that storage unit 54 is not needed for measurement, only for data collection. Circuit U3 is responsible for fitting the serial line voltage level of the RS232 interface 59. U4 produces as a sine wave generator 52 the 3.6 kHz sinus signal, and the comparator inside it squares as comparator 57 the amplified signal arriving from microphones 7.

[67] The control and processing unit 5 may be equipped with a standard 59 interface, which may be connected to a computer in a manner known from prior art, and the detected and measured data may be further processed by a dedicated computer software.

[68] In a preferred embodiment, tube 8 is a silicone tube with an inner diameter of 2 mm, pulled onto the connecting branch of the housing holding the arrangement. In this case, the piezoacoustic sound emitting device 6 is fixed inside the housing, in the mouth of the connecting branch, so as to be in direct acoustic contact with tube 8.

[69] In a possible embodiment, holders 2 are designed as belts having double function.

One of the functions of the belts is to fix the position of the silicone tubes 8 positioned inside them at the appropriate respiratory points of chest and/or abdomen respiration, and to guarantee the adequate stretching of silicone tubes 8 in case of the movement of the abdomen and the chest. The other function of the belts is to hold in adequate position the arrangement presented above, as well as the battery or accumulator holder connected to it, in which the batteries of accumulators providing for the electric power supply of the units may be placed.

[70] Figure 4 shows a preferred design of a possible holder 2 of the proposed arrangement. In the presented embodiment, the belt constituting holder 2 is made of rubberized strap 9 of a width of 50 mm and a length of 850 mm. On one end of strap 9, the 10a 'loop' side of a Velcro fastener of 10 of 50 mm width and 310 mm length is sewn. At the end of strap 9, the 10b 'hook' side of a Velcro fastener 10 of 30 mm width and 60 mm length is sewn. On the middle of rubberised strap 9, a narrower, also rubberized, strap 11 of 30 mm width and 830 mm length is sewn, so that sewing 12 should not hinder the stretching of straps 9, 11 - this may be ensured, for example, by so-called 'zikk-zakk' sewing -, and a part 13, of 10 mm length, not sewed together, is left at each of the two ends. A silicone tube 8 of 4 mm external diameter, 2 mm inner diameter and 1500 mm length is pulled between the two straps 9, 11 (not shown in Fig. 4), so that its two ends extend by 40-40 cm over the unsewn parts 13.

[71] The main design criterion has been throughout the process to assemble a low-energy arrangement to ensure more lasting measurements. The other essential criterion was that the arrangement was to operate in a highly specific environment. In the design of most medical instruments, it is no criterion that the physiological processes of the patient should be disturbed as little as possible during the diagnostic process. The arrangement to be created here, however, must take that, too, into consideration - that is, the normal physiological process of sleep must not be disturbed.

[72] Although the examples presenting the essence of the invention in the above description refer to the human body, to sound frequency signal sequence and to one or more microphones, and the proposed arrangement and method is described with their help, it will be obvious for those skilled in the art that the basic principles of the arrangement and the method are applicable to any body, hence even the body of an animal, and a professional aware of the technical state of the art and the solutions presented in the description will be able to create also a different arrangement, which, however, will also fall within the scope of this invention based on the disclosure of the description.

[73] List of reference signs

[74] 1 body

[75] 2 holder

[76] 3 motion sensor

[77] 4 sensor unit

[78] 5 control and processing unit

[79] 6 sound emitting device

[80] 7 microphone

[81] 8 tube

[82] 9 strap

[83] 10a loop' side

[84] 10b 'hook' side

[85] 11 strap

[86] 12 sewing

[87] 13 part

[88] 51 clock pulse generator

[89] 52 sine wave generator

[90] 53 processor

[91] 54 storage means [92] 55 amplifier

[93] 56 filter

[94] 57 zero crossing detector

[95] 58 power supply

[96] 59 interface

Claims

[1] 1. An arrangement for respiration detection and/or measurement, comprising: at least one holder (2) associated with at least one specific part of a living body

(i); a sensor unit (4) detecting parameter change provoked by the position change or movement of the living body (1) in direct relation to respiration, whereas the sensor unit (4) is assigned to holder (2), and the sensor unit (4) is connected to a control and processing unit (5); a signal sequence generator (52, 6), the signal sequence generator (52, 6) is fixed on holder (2); a power supply (58) powering the several stages and units of the arrangement; characterized in that it comprises a carrier element (8) which conducts the signal sequence generated by the signal sequence generator (52, 6) to the sensor unit (4), and the control and processing unit (5) connected to the sensor unit (4) is realised as a unit (5) detecting and where appropriate measuring the change of propagation of the signal sequence over time.

2. The arrangement according to claim 1 characterized in that the holder (2) associated with a specific part of the living body (1) is a holder (2) placed around the chest.

3. The arrangement according to claim 1 characterized in that the holder (2) associated with a specific part of the living body (1) is a holder (2) placed around the abdomen.

4. The arrangement according to claim 1 characterized in that the holder (2) associated with a specific part of the living body (1) are holders (2) placed around the abdomen and the chest.

5. The arrangement according to any one of claims 1 to 4 characterized in that the holder (2) is realised as a belt.

6. The arrangement according to claim 5 characterized in that the belt constituting holder (2) is adjustable so as to fit bodies (1) of various sizes.

7. The arrangement according to claim 6 characterized in that the belt is made of an elastic material.

8. The arrangement according to claim 6 characterized in that the belt is realised as a rubberised strap.

9. The arrangement according to claim 6 characterized in that the belt comprises a rubberised strap (9) inset.

10. The arrangement according to claim 6 characterized in that at the end sections of an open-type belt co-operating Velcro fastener segments (10a, 10b) are fixed.

11. The arrangement according to any one of claims 5 to 10 characterized in that the belt is associated with a shoulder strap.

12. The arrangement according to claim 1 characterized in that the sensor unit (4) contains at least one microphone (7).

13. The arrangement according to claim 1 characterized in that the signal sequence generator (52, 6) consists of an acoustic signal generator (52) and a sound emitting device (6) connected to it.

14. The arrangement according to claim 1 characterized in that the acoustic signal generator (52) is an audio frequency signal generator.

15. The arrangement according to claim 14 characterized in that the audio frequency signal generator is a sine wave generator.

16. The arrangement according to claim 14 or 15 characterized in that the sine wave generator is quartz-controlled.

17. The arrangement according to claim 1 characterized in that the carrier element conducting the signal sequence to the microphone (7) of the sensor unit (4) is a tube (8) made of elastic material.

18. The arrangement according to claim 17 characterized in that the tube (8) is a silicone tube.

19. The arrangement according to claim 1 characterized in that the sound emitting device is a piezoacoustic emitter (6).

20. The arrangement according to claim 1 characterized in that the signal sequence generator (52, 6) is fixed on the holder (2) in an adjustable position.

21. The arrangement according to claim 1 characterized in that the microphone (7) is fixed on the holder (2) in adjustable position.

22. The arrangement according to claim 1 characterized in that the control and processing unit (5) comprises an input amplifier (55), a filter (56) connected to the output of the input amplifier (55), a comparator (57) connected to the output of the filter (56) and a processor (53) constituting a unit measuring the difference in time, one input of the processor (53) is connected to the output of the comparator (57) and a second input of the processor (53) is connected to the output of the sine wave generator of the signal sequence generator (52), and a measurement data logger is connected to an output of the processor (53).

23. The arrangement according to claim 22 characterized in that the measurement data logger comprises replaceable semiconductor storage means (54).

24. The arrangement according to claim 23 characterized in that the replaceable semiconductor storage means (54) is a memory card or a pen-drive.

25. The arrangement according to claim 1 characterized in that the power supply (58) consists of battery cells arranged in a battery holder.

26. The arrangement according to claim 1 characterized in that the power supply (58) is a rechargeable battery.

27. The arrangement according to any one of claims 1, 25 or 26 characterized in that the power supply (58) is removably fastened on holder unit (2).

28. A method for respiration detection and/or measurement, comprising the steps of detecting the position change or movement of a living body (1) occurring in direct relation to respiration by monitoring change in at least one parameter associated with the position change or movement, in case of respiration measurement, recording the parameter change over time; characterized by detecting, as a parameter associated with the position change or movement, a change of propagation over time of an acoustic signal sequence conducted along the body part involved in respiration.

29. The method according to claim 28 characterized by emitting an audio frequency signal as the acoustic signal sequence.

30. The method according to claim 29 characterized by emitting a sine wave signal as the audio frequency signal.

31. The method according to any one of claims 28 to 30 characterized by detecting, as a change over time of the propagation of the acoustic signal sequence, the change of the phase difference between the emitted signal sequence and the signal sequence reaching the sensor unit on a longer distance due to respiration.

32. The method according to claim 31 characterized by detecting the phase differences by zero crossing detection.

33. The method according to any one of claims 28 to 32 characterized by influencing the accuracy of the measurement by the chosen frequency of the acoustic signal sequence.