JPS62148653A - Stethoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates primarily to a medical stethoscope, and more particularly to a stethoscope that amplifies breathing sounds and heart sounds inside a patient's body using an electrical amplifier to adjust the volume. This invention relates to a small and lightweight electric stethoscope whose audio output can be electrically analyzed and listened to by a large number of people to make a comprehensive diagnosis.

BACKGROUND OF THE INVENTION Stethoscopes have long been known as medical devices that listen to the breathing sounds and heart sounds inside a patient's body to aid in diagnosing diseases. This stethoscope basically consists of a chess piece that generally has a diaphragm, an ear tip that is inserted into the ear of the diagnostician, and a tube that communicates the chess piece and the ear tip. By placing the pieces 1 to 1 on the patient's chest, etc., it is possible to hear internal heart sounds, breathing sounds, and the sounds of intestinal contractions (to the stomach) directly through the ear tips.

Problems to be Solved by the Invention The stethoscope according to the prior art described above collects internal body sounds with the chest piece, propagates the sounds inside the tube, and listens to them with the ear tips.Theoretically, the diagnostician can You can get the same feeling as listening by placing your ear directly on the affected area. Therefore, it has the advantage of being the most realistic, but on the other hand, since the volume cannot be adjusted, it is often difficult even for people with normal hearing to capture minute sounds and listen carefully to them. Additionally, it is difficult for a diagnostician with diminished hearing ability (for example, when a doctor becomes deaf due to old age) to hear small internal sounds. The current situation is that we are dealing with this based on intuition. This is not desirable when considering the role of the stethoscope as a medical device, that is, the important function of diagnosing the condition of an affected part of the human body by listening to internal sounds.

Furthermore, as mentioned above, conventional stethoscopes are not very realistic, or when listening to low-pitched sounds such as the sounds of intestinal contractions or rolling sounds, the hearing is interrupted by high-pitched sounds such as the sounds of breathing in the lungs. Sometimes it becomes difficult, and vice versa.

Moreover, even among people who use stethoscopes, there are people who have difficulty hearing high-pitched sounds, and others who have difficulty hearing low rl sounds (generally, as we get older, our eardrums thicken, It's especially difficult to hear the 'li r'↑ part). In this case, the superiority of reality actually becomes a disadvantage.

Furthermore, with conventional stethoscopes, the diagnostician inserts an ear tip into his or her ear, so only the individual diagnostician can be embarrassed, and therefore many experienced doctors, nurses, etc. It was impossible for people to simultaneously auscultate and make a comprehensive diagnosis. Furthermore, conventional stethoscopes have a device that prevents signal sound interference when the tube comes into contact with the user's face.
A gold FF1L tube is used for the connection between the tube and the ear tip. This resulted in an overall bulky configuration, which was also inconvenient for Be(:+F).

Purpose of the Invention The present invention has been proposed in view of the above-mentioned problems inherent in conventional stethoscopes, and has been proposed to suitably solve the problems by constructing the stethoscope with an electrical amplifier. , converting the patient's internal sounds into electrical signals and subjecting the output to various types of electrical processing, allowing simultaneous auscultation by multiple people and allowing internal sounds at specific frequencies to be heard; The aim is also to make the entire auscultation system smaller and lighter.

Means for Solving the Problems In order to suitably solve the above-mentioned problems, the present invention provides an auscultation chestpiece comprising a sound pickup microphone that picks up audio signals and converts them into electrical signals, and this chestpiece. The present invention is characterized by the use of an electrical amplifier comprising an amplifier circuit section connected to the circuit to amplify the electrical signal in a volume-adjustable manner, and a loudspeaker for converting the amplified electrical signal back into an audio signal. In this case, it is preferable to use earphones as a loudspeaker for converting electrical signals into audio signals. As an alternative to this, it is more preferable to use a speaker as the loudspeaker.

Embodiments Next, preferred embodiments of the stethoscope according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a block diagram of one embodiment of the listening device according to the present invention, which basically consists of a sound collection microphone 1, an amplifier circuit section 2, and a loudspeaker 3. This sound collection microphone 1 is a transducer that collects audio signals and converts them into electrical signals, and is incorporated into an auscultation chestpiece. Also, an earphone is used as the loudspeaker 3, and the earphone is configured to function as an ear tip that is inserted directly into the ear of the diagnostician. Depending on the specific application, this loudspeaker 3 can use two-pronged earphones or lightweight headphones to prevent interference from external sounds. The connection line between the sound collection microphone 1, the amplifier circuit section 2, and the loudspeaker 3 is as follows.

A lead wire is used, or the sound collection microphone 1 is integrated into the amplifier circuit section 2, and the amplifier circuit section 2 is directly connected to an earphone as a loudspeaker 33 by a lead wire.
It is also possible to adopt a method in which headphones are used as the loudspeaker 3, the amplifier circuit section 2 is integrated into the headphones, and the headphone is connected to a chest piece as the sound collection microphone 1 by a lead wire.

The amplifier circuit section 2 incorporates a variable resistor (not shown) or a multi-stage attenuator, and by adjusting the volume t1 etc. from the outside, changes the amplification amount continuously or stepwise, and adjusts the loudspeaker appropriately. It has a structure that allows you to adjust the volume to the desired level. FIG. 2 is a schematic configuration diagram showing one embodiment of the amplifier circuit section 2. As shown in FIG. The present amplifier circuit section 2 is composed of a preamplifier P and a main amplifier M, and the preamplifier P is composed of an amplifier A configured as an active element t, a fixed resistor & which is grounded at one end, and a resistor R which is a passive element. and a connection element Z formed by a combination of conductance C and conductance C, and the whole constitutes a negative feedback amplifier circuit. The connecting element 2 is
Since the impedance value of the contactance C that constitutes this changes depending on the frequency, the impedance value of the connecting element Z as a whole also changes depending on the frequency. Each connection element Z1 adjusts the amount of negative feedback by suitably changing the impedance value depending on the frequency, and corrects the frequency amplification characteristic of the entire amplifier circuit, where the amplification factor changes depending on the frequency. 2, the connection element Z 21 Z , +χ, which is set to a linear configuration, is
Each connection element Z1 is configured to have an impedance change characteristic with respect to the frequency (i.e., a change in the amount of negative feedback) and an impedance change characteristic (i.e., a change in the amount of negative feedback) with respect to a different frequency. It is set to be high and low, and the preamp P
is configured to function as an equalizer amplifier. These connecting elements Zj12, 2. may each be set to a constant value at the manufacturing stage, or it is preferable to use a variable capacitor or a variable resistor so that the frequency amplification characteristics can be varied as required by the user. In this example,
The connecting element z2 is designed to emphasize high frequencies.
It is assumed that the connection element Z3 is set to emphasize the mid-range frequency, and the connection element Z4 is set to emphasize the low-range frequency.
By switching the contacts of the connecting elements z,, z2.
z3. The configuration is such that the negative feedback path of the preamplifier P can be switched to z.

The main amplifier M connected to the next stage of the preamplifier P has a built-in variable resistor or multi-stage attenuator linked to a volume or toggle switch (not shown), and can be adjusted continuously by adjusting the volume externally or in stages by a toggle switch. The structure is such that the amplification amount of the entire amplifier circuit section 2 can be appropriately changed by changing the amplifier accordingly.

3+7] is a schematic configuration diagram showing another embodiment of the amplifier circuit unit 2. The amplifier circuit section 2 shown in FIG. 2 is composed of a preamplifier p and a main amplifier M, but in this embodiment,
A filter section F is connected before the preamplifier P. However, the preamplifier P does not have an equalizer function, and the preamplifier P and main amplifier M are configured to have linear frequency amplification characteristics. The filter part F includes a bypass filter HPF that attenuates the mid-low range of frequency components and mainly passes the high-frequency components, a low-pass filter LPF that attenuates the mid-high range of one frequency component and mainly passes the low-frequency components, and a filter. Line L1 that does not allow
It is composed of. Then, by switching the contacts of the switch SW2 from outside the amplifier circuit section 2, the respective inputs are passed through the bypass filter Hl) F or the low-pass filter LPF, and are then passed through the preamplifier P via the line L without passing through the filter. It is configured so that it can be input. This filter may be set to have a constant frequency attenuation characteristic at the manufacturing stage, or by being configured with a variable capacitor and a variable resistor, the user can arbitrarily change the frequency attenuation characteristic of the filter. It is also suitable to configure it so that it can be done.

FIG. 4 shows a block diagram of a configuration according to another embodiment of the present invention. That is, in the embodiments shown in FIGS. 1 to 3, the sound collection microphone 1 and the amplification circuit section 2 are connected by wire. In this embodiment, the sound collection microphone 1 and the amplification circuit section 2 are connected separately. configured. For example, a wireless transmitter 4 is connected to the sound collection microphone 1 to constitute a wireless transmitter 6 as a whole, and the sound collected by the sound collection microphone 1 is transmitted to the wireless transmitter 4.
The signal is converted into an electrical signal and transmitted by radio waves. on the other hand.

A wireless receiver 5 is integrally connected to the front stage of the amplifier circuit section 2 to constitute a wireless receiver equalizer section 7. and wireless receiver 5
receives the radio wave and amplifies it in the amplifier circuit section 2. Note that the amplifier circuit section 2 has a structure similar to that of the amplifier circuit section of the above-described embodiment.

FIG. 5 shows a block diagram of a configuration according to yet another embodiment of the present invention, and the configuration is the same as that in FIG. 1 except for the recording section 8. The amplifier circuit section 2 is incorporated into a small-sized recorder 9 equipped with a recording section 8. This Dfl device 9 is normally used as the amplifier circuit section 2 of the stethoscope, but if necessary, by turning on the operation switch of the recording section 8 (not shown),
The sound picked up by the sound collection microphone 1 through the line L2 is directly recorded. Also, during playback, by switching the operation switch, the playback output of the recording section 8 is input to the amplifier circuit section 2 through the line L, and the configuration is such that it can be reproduced into audio with the necessary frequency amplification characteristics via the amplifier circuit section. ing.

Next, the actual use of the stethoscope according to the present invention will be explained.

After turning on the power of the stethoscope, insert the ear tips consisting of two-pronged earphones into the ears, and place the chest piece consisting of the sweat-absorbing microphone 1 against the patient's chest. An audio signal consisting of internal sounds goes up to a sound collecting microphone 1, is collected, and is converted into an electrical signal.This electrical signal is amplified by an amplifier circuit section 2, and then converted by a loudspeaker 3 into a +1 audio signal. Therefore, the diagnostician listens directly to the internal sounds 1 using the loudspeaker 3 installed on the ear tip.
I can do something rare. In this case, by adjusting the volume provided in the amplifier circuit section 2 or switching the 1-cycle switch, the volume can be increased or decreased to listen at the most appropriate volume.

For example, if you want to auscultate low sounds such as the sounds of intestinal contractions, use the second
In the stethoscope using the amplifier circuit section 2 according to the embodiment shown in the figure, by switching the switch SW□ from the connection element Z side to the connection element Z4 side, and in the stethoscope according to the embodiment shown in By switching SW2 from line L to the low-pass filter LPF side, the treble part is cut and the bass part can be heard clearly. Conversely, when it is desired to auscultate high-pitched sounds such as the breathing sounds of the lungs, the stethoscope according to the embodiment of FIG. In the auscultation H according to the embodiment shown in the figure, by switching the switch SW2 from line r, 1 to the bypass filter HPF side, the bass part is canted and the treble part can be heard mainly. If your hearing in a particular frequency band is weak, in the embodiment shown in FIG. Similarly, in the embodiment shown in FIG. 3, by switching the switch SW2 to the bypass filter HP F side and adjusting its passband attenuation characteristic, the desired frequency amplification characteristic can be obtained. , desired frequency amplification characteristics can be obtained.

In the embodiment shown in FIG. 4, the chest piece 1 and the amplifier circuit section 2 are configured as separate bodies.

The electrical signal converted by the chest piece 1 is transmitted by radio waves by the wireless transmitter 4 integrated into the chest piece, and this signal is received by the wireless receiver 5 installed in the amplifier circuit section 2. The amplification circuit section 2 is configured to amplify the signal. Since the sound collection microphone 1 is incorporated into the wireless transmitter 6 in this manner, diagnostic information based on internal sounds is transmitted as radio waves simply by applying the chest piece to the affected area of the patient.

Therefore, the diagnostician only needs to carry the chest piece of the stethoscope, and the system can be made extremely small and lightweight. Note that if a large number of wireless receiving sections 7 incorporating the amplifier circuit sections 2 are prepared, a plurality of people can listen to the internal sounds of the patient at the same time.

For example, in a university hospital or the like, when a plurality of interns take part in rounds, one person can place the sound collection microphone 1 against the affected area so that the other people can listen to the same sound at the same time.

In the embodiment shown in FIG.
The amplifier circuit section 2 is usually used as an amplifier for the stethoscope, and the audio signal picked up by the chest piece 1 can be directly recorded as necessary. During playback, the playback output of the recorder 8 is input to the amplifier circuit section 2 by switching an operation switch (not shown). In the amplifier circuit section,
If the amplifier circuit section of the embodiment shown in FIG. 2 or 3 is used, it is possible to listen to reproduced sound with the necessary frequency amplification characteristics via the amplification circuit section.

Effects of the Invention As described above, according to the stethoscope according to the present invention, the volume can be increased for auscultation by adjusting the volume or changing the toggle switch. too.

It is convenient because you can clearly hear the patient's internal sounds. Furthermore, even people with normal hearing can listen to weak sounds at a high volume when they want to listen to weak sounds, especially when fishing for heavy fish, so this is suitable. Furthermore, if a speaker is used as the loudspeaker 3 instead of earphones, auscultation can be performed by many people at the same time.

The stethoscope according to the present invention uses an integrated circuit in the amplifier circuit section 2 and uses a small power source such as a mercury battery, thereby making the stethoscope smaller and lighter. For example, a sound collection microphone, an amplification circuit, and a power supply are integrated into a case packed in a Matsushi box.
It can be configured to be connected to earphones with a lead wire, or it can be configured to have an amplification circuit and a power source built into the headphones and connected to a microphone made of a chest piece using a lead wire. Furthermore, as shown in the embodiment shown in FIG. 4, the sound collection section and the amplification circuit section may be constructed in a wireless manner.

Since the lead wire can be eliminated, the stethoscope can be made with excellent portability and ease of handling.

Furthermore, if the amplifier circuit section shown in the embodiment shown in FIGS. 2 and 3 is used, the treble part is attenuated and the bass part is emphasized as necessary, and conversely, the bass part is attenuated and the treble part is emphasized. By doing so, it is possible to match the frequency characteristics of the intracorporeal tf that is most desired to be auscultated. Similarly, people who have poor hearing ability for high and low frequencies,
Since the amplification characteristics of the amplification circuit of the stethoscope can be adjusted to the required frequency characteristics, the stethoscope can be made very easy to use.

Furthermore, by incorporating a recording section as in the embodiment shown in FIG. 5, internal sounds can be recorded, making it possible to compare the progress of a patient's treatment with the previous one and convert it into data, or to compare other cases.

Furthermore, by using a wireless system as shown in the example of the 4th File, it becomes possible for multiple people to listen to the patient's internal sounds at the same time by using multiple wireless receivers, which is especially useful for medical students. It is effective in education, etc.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the stethoscope according to the present invention, FIG. 2 is a circuit configuration diagram showing one embodiment of the amplifier circuit section,
FIG. 3 is a circuit groove diagram showing another embodiment of the amplifier circuit section in FIG. 2, FIG. 4 is a block diagram of a configuration according to another embodiment of the present invention, and FIG. 1 shows a block diagram of a configuration according to an embodiment of the present invention. 1...Sound collection microphone 2...Amplification circuit section 3...
Loudspeaker 4...Radio transmitter 5...Radio receiver 9...Small recorder FIG, I FIG, 4 FIG, 5 FIG, 2

Claims (9)

[Claims] (1) An auscultation chestpiece consisting of a sound pickup microphone that picks up audio signals and converts them into electrical signals; an amplification circuit connected to the chestpiece to amplify the electrical signals in a volume-adjustable manner; A stethoscope characterized by using an electrical amplifier configured with a loudspeaker that converts electrical signals back into audio signals. (2) The stethoscope according to claim 1, wherein an earphone is used as a loudspeaker for converting electrical signals into audio signals. (3) The stethoscope according to claim 1, wherein a speaker is used as a loudspeaker for converting electrical signals into audio signals. (4) The amplifier circuit section has a characteristic capable of linearly amplifying a wide band, and is configured to be able to selectively switch among a plurality of set frequency amplification characteristics.
The stethoscope according to any one of Items 1 to 3. (5) The stethoscope according to claim 4, which incorporates an equalizer circuit to switch the frequency amplification characteristics in the amplifier circuit section. (6) The stethoscope according to claim 4, which incorporates a bandpass filter to switch the frequency amplification characteristic in the amplifier circuit section. (7) The frequency amplification characteristic of the amplifier circuit section can be arbitrarily set to be adjustable, and the frequency amplification characteristic of the amplifier circuit section can be switched to the adjusted frequency amplification characteristic. The stethoscope according to any one of Items 1 to 4. (8) The chest piece and the amplifier circuit section are configured as separate bodies, and the electric signal converted by the chest piece is transmitted by radio waves by a wireless transmitter integrated into the chest piece, and this signal is transmitted to the 8. A stethoscope according to any one of claims 1 to 7, wherein the stethoscope is configured to be received by a wireless receiver incorporated in an amplifier circuit and amplified by the amplifier circuit. (9) The amplification circuit section is incorporated into a small recorder, and the amplification circuit section is always used as an amplifier for a stethoscope,
9. A stethoscope according to any one of claims 1 to 8, characterized in that the stethoscope is configured to record audio signals collected by the chestpiece as necessary.