WO2007018324A1

WO2007018324A1 - Electronic stethoscope head

Info

Publication number: WO2007018324A1
Application number: PCT/KR2005/002810
Authority: WO
Inventors: Hyun-Kook Ahn
Original assignee: Pishon High Tech. Co., Ltd.
Priority date: 2005-08-09
Filing date: 2005-08-25
Publication date: 2007-02-15
Also published as: KR100706842B1; KR20070018334A

Abstract

Disclosed herein is an electronic stethoscope head which includes a piezotransducer to convert sounds to electrical signals. The electronic stethoscope head is brought into contactwith a patient to collect the sounds and then convert the sounds into electrical signals. The electronic stethoscope head includes a head case and having a cylindrical shape opened at upper and lower portions thereof, and a transducer unit fixed inside the head case and comprising a piezotransducer to convert the sounds to the electrical signals. With the piezotransducer having a secure structure, the electronic stethoscope head can be easily manufactured and manipulated, and has an enhanced response rate in a lower frequency band, thereby enabling precise diagnosis.

Description

ELECTRONIC STETHOSCOPE HEAD

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an electronic stethoscope head, and more particularly to an electronic stethoscope head which includes a piezotransducer to convert sounds to electrical signals.

Description of the Related Art

In general, a stethoscope is a medical device for listening to internal sounds of a patient, such as heartbeat and breathing. As shown in Fig. 4, in order to help the doctor to clearly listen to the internal sounds of the patient, a conventional stethoscope comprises a stethoscope head 100 adapted to contact the patient to collect the sounds, a flexible tube 300 connected to the stethoscope head 100 to transmit the sounds, and an earpiece 200 positioned at either distal end of the flexible tube 300 so as to fit into each ear of a doctor, and adapted to output the internal sounds of the patient.

However, since the conventional stethoscope transmits the sounds in a form of a sound wave, it is difficult to amplify a low level sound into a high level sound, and to listen to such a low level sound with such a conventional stethoscope. In addition, the conventional stethoscope allows noise to be also transmitted together with the internal sounds, frustrating precise diagnosis, and cannot store the internal sounds of the patient as medical records.

In order to solve the problems described above, an electronic stethoscope has been developed, which converts only the internal sounds into electrical signals, amplifies the electrical signals through a separate amplification circuit, and outputs the amplified signals to the outside through a speaker. Use of such an electronic stethoscope has been rapidly increased in recent years, as medical activities such as storage of the medical records and diagnosis have become digitalized. As shown in Fig. 5, an the electronic stethoscope head 100 comprises a conical head case 101 opened at a lower portion to collect sounds, a vibration diaphragm 102 fixed to a lower surface of the head case 101 to accept the sounds, and a microphone 103 mounted on an inner surface of the vibration diaphragm 102 to convert the sounds into electrical signals, in which the microphone 103 is connected to an amplification circuit, a speaker or earphones via a lead line 104 and the like to allow the electrical signals to be outputted. However, since such a conventional electronic stethoscope head employs a typical condenser microphone, the electronic stethoscope head has a lower response rate or suffers from non-uniform conversion of sound at frequencies bellow 200 Hz. In this regard, since most internal sounds of the patient have frequencies below 200 Hz, the conventional electronic stethoscope head has problems in that precise diagnosis is difficult, and in that severe distortion occurs due to modification of the sounds.

In order to solve the problems described above, the conventional electronic stethoscope head includes a piezoelectric polymer film sensor instead of the condenser microphone. However, although the piezoelectric polymer film sensor has an advantage of constant response rate from a lower frequency band to an upper frequency band, there is a problem in that, since it is produced as a thin film having a thickness of 0.2 mm or less, the piezoelectric polymer film sensor has difficulties in manufacture and manipulation, and requires high manufacturing costs.

SUMMARY OF THE INVENTION

Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an electronic stethoscope head which includes a piezotransducer to convert sounds to electrical signals .

It is another object of the present invention to provide an electronic stethoscope head which is not harmful to a patient while efficiently transmitting sounds through the piezotransducer .

It is another object of the present invention to provide an electronic stethoscope head which maximizes collecting capability of the sounds while preventing current leakage of the piezotransducer. In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of an electronic stethoscope head to collect sounds through a sound detection unit via contact with a patient, including: a cylindrical head case opened at upper and lower portions thereof; and a transducer unit fixed inside the head case and comprising a piezotransducer to convert the sounds to electrical signals .

The transducer unit may include a silicone plate attached to a lower opening of the head case to close the opening; a silicone pad attached to a lower surface of the silicone plate and exposed to an outside of the head case to contact the patient; a cushion pad attached to an upper surface of the silicone pad and inserted to an interior of the head case; and the piezotransducer attached to an upper surface of the cushion pad and having an outer edge supported by an inner surface of the head case.

The electronic stethoscope head may further include a fixing ring formed of non-acetic acid silicone between the outer edge of the piezotransducer and the inner surface of the head case.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

Fig. 1 is an exploded perspective view illustrating an electronic stethoscope head in accordance with one embodiment of the present invention;

Fig. 2 is a perspective view illustrating the assembled electronic stethoscope head of Fig. 1; Fig. 3 is a cross-sectional view of Fig. 2; Fig, 4 is a perspective view illustrating one example of a conventional electronic stethoscope; and

Fig. 5 is a cross-sectional view of a head for the conventional electronic stethoscope.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described hereinafter with reference to the drawings.

Fig. 1 is an exploded perspective view illustrating an electronic stethoscope head in accordance with one embodiment of the invention, Fig. 2 is a perspective view illustrating the assembled electronic stethoscope head of Fig. 1, and Fig. 3 is a cross-sectional view of Fig. 2. As shown in the drawings, the present invention provides an electronic stethoscope head adapted to collect sounds of various internal organs via contact with a patient so as to allow a doctor to listen to the sounds through the electronic stethoscope head. For this purpose, it includes a transducer unit 20 positioned in a head case 10a and 10b to convert the sounds into electrical signals by mean of a piezotransducer 24 equipped therein, thereby allowing precise diagnosis as well as allowing easy manufacturing and convenient manipulation.

The head case 10a and 10b constitutes a body of the electronic stethoscope head. The head case 10a and 10b has an inner space, a lower side of which is open to guide the sounds into the head case 10a and 10b in diagnosis, and an upper side of which is also open to guide a lead line 30 from an interior of the head case 10a and 10b to a separate amplification circuit, a speaker, an earphone, and the like. Preferably, the head case 10a and 10b is divided into an upper case 10b and a lower case 10a so as to allow easy assembly of the transducer unit 20 inserted into the head case 10a and 10b.

The transducer unit 20 is protected by the head case 10a and 10b, and serves to collect the sounds of the various internal organs while contacting a skin of the patient and to convert the sounds into electrical signals. The transducer unit 20 includes a silicone plate 21 attached to a lower opening of the head case 10a and 10b, a silicone pad 22 and a cushion pad 23 respectively attached to upper and lower surfaces of the silicone plate 21, and the piezotransducer 24 fixed inside the head case 10a and 10b while contacting the cushion pad 23.

The silicone plate 21 closes the lower opening of the head case 10a and 10b, and serves to prevent foreign substances from being introduced to the head case 10a and 10b while reducing loss of vibration of the sounds due to radiation when the internal sounds of the patient are transmitted into the head case 10a and 10b. Preferably, the silicone plate 21 is formed of a non-toxic silicone material, and has a thickness of about 0.2 mm so as to allow efficient transmission of the vibration.

The silicone pad 22 is brought into direct contact with the patient to receive the vibration of the sounds . The silicone pad 22 is integrally attached to the lower surface of the silicone plate 21 and exposed to an outer side of the head case 10a and 10b. The silicone pad 22 has a planar lower surface to maximize a contact area with the patient, allowing the internal sounds of the patient to be transmitted to the silicone pad 22 via the vibration of the skin.

The cushion pad 23 serves to allow the vibration of the sounds transmitted from the silicone plate 21 and the silicone pad 22 to be transmitted to the piezotransducer 24, as will be described hereinafter. The cushion pad 23 is formed of a soft synthetic resin, such as silicone, and is integrally attached to the upper surface of the silicone plate 21 such that the cushion pad 243 is inserted into the head case 10a and 10b. The piezotransducer 24 serves to convert the internal sounds of the patient transmitted in the form of vibration via the silicone pad 22, the silicone plate 21, and the cushion pad 23 to electrical signals. The piezotransducer 24 is a typical piezotransducer, which can convert sound into electrical signals.

The piezotransducer 24 has a secure multilayer structure wherein electrodes and ceramic layers are stacked therein, and exhibits a good response rate in a low frequency band. Thus, it can be easily manufactured, and enables precise diagnosis with the sounds while allowing convenient manipulation.

In addition, with an outer edge fixed to an inner surface of the head case 10a and 10b, a lower surface of the piezotransducer 24 through which the sounds is transmitted is brought into intimate contact with the cushion pad 23, and an upper surface of the piezotransducer 24 is coupled to the lead line 30 for supplying the electrical signals such that the electrical signals converted from the sounds are supplied to the speaker or the amplification circuit, so that the vibration of the cushion pad 23 is effectively transmitted to the piezotransducer 24.

As a result, when examining a patient using an electronic stethoscope including the head of the invention, the silicone pad 22 of the head case 10a and 10b is brought into contact with a portion of the patient' s body, and sounds of various internal organs are converted to electrical signals by the piezotransducer 24 after passing through the silicone pad 22, silicone plate 21, cushion pad 23. Thus, with the piezotransducer 24, the electronic stethoscope head can be easily manufactured, and exhibits precise conversion from the sounds to electrical signals, thereby enabling more precise diagnosis .

Furthermore, a fixing ring 25 formed of a soft material, such as non-acetic acid silicone, having adhesion and resiliency is positioned between the outer edge of the piezotransducer 24 and the inner surface of the head case 10a and 10b so that the outer edge of the piezotransducer 24 is separated a predetermined distance (about 0.5 mm) from the inner surface of the head case 10a and 10b. As a result, the fixing ring 25 prevents the piezotransducer 24 from contacting the head case 10a and 10b to avoid current leakage from the piezotransducer 24, shields entrance of external electrical signals such as static electricity to allow precise operation of the piezotransducer 24, and absorbs impact applied to the piezotransducer 24 to prevent damage of the piezotransducer 24.

In addition, since the fixing ring 25 is formed of non-acetic acid silicone, it can prevent oxidation of various metallic components included in the piezotransducer 24, so that the piezotransducer 24 can be operated stably and precisely for a long time of period.

As apparent from the above description, according to the present invention, the electronic stethoscope head includes a piezotransducer having a secure structure to convert sounds to electrical signals, so that the electronic stethoscope head can be easily manufactured and conveniently manipulated, and has an enhanced response rate in a lower frequency band, thereby enabling precise diagnosis. In addition, according to the present invention, the electronic stethoscope head includes a silicone plate and a silicone pad provided at a lower portion of a head case while contacting the piezotransducer so as to allow efficient deliver of the sounds to the piezotransducer, thereby minimizing skin toxicity, and ensuring more precise and convenient diagnosis via the stethoscope.

Furthermore, according to the present invention, a fixing ring of the electronic stethoscope head prevents current leakage of the piezotransducer while maximizing collecting capability of the sounds, so that the piezotransducer can be operated more stably and precisely, thereby enabling more precise diagnosis .

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

WHAT IS CLAIMED IS:

1. An electronic stethoscope head to collect sounds via contact with a patient and to convert the sounds into electrical signals, including: a cylindrical head case opened at upper and lower portions thereof; and a transducer unit fixed inside the head case and comprising a piezotransducer to convert the sounds into the electrical signals.

2. The electronic stethoscope head as set forth in claim 1, wherein the transducer unit includes: a silicone plate attached to a lower opening of the head case to close the opening; a silicone pad attached to a lower surface of the silicone plate and exposed to an outer side of the head case to contact the patient; a cushion pad attached to an upper surface of the silicone pad and inserted into an interior of the head case; and the piezotransducer attached to an upper surface of the cushion pad and having an outer edge supported by an inner surface of the head case.

3. The electronic stethoscope head as set forth in claim 2, further including: a fixing ring allowing the outer edge of the piezotransducer to be fixed to the head case while being separated from the inner surface of the head case.