WO1995019136A1

WO1995019136A1 - Stethoscope accessory

Info

Publication number: WO1995019136A1
Application number: PCT/GB1994/000060
Authority: WO
Inventors: Robert Parnell Mandeville
Original assignee: Under Limited
Priority date: 1992-07-07
Filing date: 1994-01-12
Publication date: 1995-07-20

Abstract

An accessory for stethoscope head (1) consists of a collar (8) formed from resilient material of relatively low thermal and acoustic conductivity which collar (8) is sized to accommodate the body (4) of a stethoscope head (1) to which it may be fitted by frictional engagement and provide a peripheral rim extending beyond the rim (7) of the bell to provide a deformable surface for contacting a subject to be examined, the said collar being stabilised for such use at least in part by having a surface remote from said rim in abutment with the mounting for the diaphragm (2) of the stem (6).

Description

STETHOSCOPE ACCESSORY

This invention relates to a stethoscope head accessory and in particular a protective external collar for a stethoscope head.

Medical stethoscope heads are conventionally made of metal materials since metals are extremely durable, give good sound reproduction and can be machined into precise receiver shapes. Normally such metal stethoscope heads have one major disadvantage well-known to patients and particularly to young children. The metal material gives a chill or cold sensation when applied to the body. Furthermore, for effective functioning of the stethoscope bell, there needs to be an airtight seal between the source of the sound (the body skin) and the air column in the stethoscope leading to the earpieces. Although skin is deformable there are some situations, for example over the bones of the ribs, where an airtight seal becomes virtually impossible due to the hard composition of the stethoscope head.

Attempts to overcome this problem have been made by providing stethoscope heads having silicone rubber rings which are fitted onto the rim of the diaphragm of the stethoscope head. The disadvantage of these rings is that they also produce a cold feeling on the skin and they do not form an airtight seal on problem areas of the body.

Other prior art stethoscope heads have closed foam plastics rings fitted around the rim, but these lack the robustness of the rubber and very soon loosen and split.

The aim of the present invention is to provide a stethoscope head accessory which obviates or mitigates the aforementioned disadvantages.

SUBSTITUTESHEET According to the present invention, there is provided an accessory for a stethoscope head consisting of a collar formed from a resilient material of relatively low thermal conductivity which collar is sized to accommodate the body of a stethoscope head to which it may be fitted by frictional engagement and provide a peripheral rim extending beyond the bell to provide a deformable surface for contacting a subject to be examined, wherein the said collar can be stabilised for such use at least in part by having a surface remote from said rim in abutment with the diaphragm mounting or the tubular stem of said head.

Preferably the resilient material is a closed foam plastics material which is acoustically insulating, and may be selected from polyethylenes or polypropylenes.

The collar is of generally cylindrical shape and the said rim for contacting the skin of a subject is preferably of rounded or tapered configuration, but may be any shape suited to the purpose.

The present invention will now be described below by way of example only, with reference to the accompanying drawings which illustrate one specific embodiment in which:

Figure 1 is a cross-sectional view of a stethoscope head with an accessory in accordance with this invention fitted.

Figure 2 is a plan view of the stethoscope head of

Figure 1.

Figure 3 is an elevation of the stethoscope head of Figure l.

Referring to Figures 1-3, a stethoscope head 1 has a conventional diaphragm 2 in back-to-back relation with an open bell 3 separated by an intermediate body portion 4. At

SUBSTITUTESHEET the apex of the diaphragm and bell respectively are aligned apertures, leading to a bore 5 through the body. The apertures are aligned substantially perpendicular to the bore.

The body is fitted with a conventional tubular stem 6.

The stem is, in turn, conventionally adapted to rotate within and relative to the body portion 4 and has conventional aligning means to align at least the opening in the stem with either aperture or to provide a sound passageway from the selected and properly aligned bell 3 or diaphragm 2 to the stem. The stem is adapted to be connected to a conventional binaural head set.

The bell has a continuous peripheral rim 7. The rim 7 lies in a plane spaced outwardly from and at all places equidistant from the central aperture. This rim 7 is contiguous with an outer annular wall and an inner annular wall. The inner annular wall is bell-shaped with its outer extremities approaching and parallel with the outer wall.

An accessory of this invention consists of a substantially annular collar 8 which when pushed over the bell of the stethoscope head stays in place by gripping the body 4 of the stethoscope and is supported preferably by the mount for the diaphragm 2 or the stem 6. The collar 8 may be formed of closed foam plastics material such as polyethylenes or polypropylenes or any appropriate elastomeric material which may be stretched or distorted to be snapped over the body of the stethoscope 4. The annular collar 8 when in place provides a rim which projects beyond the top surface of the bell 3.

In use of the present invention the collar 8 is force- fitted over the bell to fit tightly around the body of the stethoscope and is stabilised in position for use by

SUBSTITUTESHEET abutment with the diaphragm support 2 or the stethoscope stem 6.

The advantages of the present invention are that the projection of the collar 8 beyond the end of the bell 3 thermally insulates the patient being examined from the metal body of the stethoscope. The closed foam plastics material allows some degree of deformation in response to the contours of the patient's body thereby preventing the escape of sound energy while also supplying sound insulation from ambient noise.

In an alternative embodiment the collar can be used on a stethoscope without a diaphragm, wherein the collar is stabilised purely by friction fitting upon the body of the stethoscope head by virtue of the elasticity of the selected plastics material.

SUBSTITUTESHEET

Claims

CLAIMSl. An accessory for a stethoscope head consisting of a collar formed from a resilient material of relatively low thermal conductivity which collar is sized to accommodate the body of a stethoscope head to which it may be fitted by frictional engagement and provide a peripheral rim extending beyond the bell to provide a deformable surface for contacting a subject to be examined, the said collar being stabilised for such use at least in part by having a surface remote from said rim in abutment with the diaphragm mounting or the stem.2. An accessory for a stethoscope head according to claim 1 wherein the insulating material is a closed foam plastics material.3. An accessory for a stethoscope head according to claim 2 wherein the insulating material is an elastomeric material.4. An accessory for a stethoscope head according to claim 2 wherein the insulating material is selected from polyethylenes or polypropylenes.5. An accessory for a stethoscope head according to any one of the preceding claims wherein the material selected for the collar is acoustically insulating.6. An accessory for a stethoscope head according to any one of the preceding claims wherein the material selected for the collar is thermally insulating.7. An accessory for a stethoscope head substantially as hereinbefore described with reference to and as shown in the accompanying drawings.SUBSTITUTE SHEET AMENDED CLAIMS[received by the International Bureau on 24 November 1994 (24.11.94); original claims 1 and 2 amended; new claims 8 and 9 added; remaining claims unchanged (2 pages)]

1. An accessory for a stethoscope head consisting of a collar formed from a resilient material of relatively low thermal conductivity which collar is sized to accommodate the body of a stethoscope head to which it may be fitted by frictional engagement and provide a peripheral rim extending beyond the bell to provide a deformable surface for contacting a subject to be examined, the said collar being stabilised for such use at least in part by having a surface remote from said rim in abutment with [the diaphragm mounting or] the stem.

2. An accessory for a stethoscope head according to claim 1 or claim 8 or claim 9 wherein the insulating material is a closed foam plastics material.

3. An accessory for a stethoscope head according to claim 2 wherein the insulating material is an elastomeric material.

4. An accessory for a stethoscope head according to claim 2 wherein the insulating material is selected from polyethylenes or polypropylenes.

5. An accessory for a stethoscope head according to any one of the preceding claims wherein the material selected for the collar is acoustically insulating.

6. An accessory for a stethoscope head according to any one of the preceding claims wherein the material selected for the collar is thermally insulating.

7. An accessory for a stethoscope head substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

8. A stethoscope head (1) having a body (4) upon which there is provided a mounting for a diaphragm (2) , a bell (3) , and a stem (6) , and further comprising a collar (8) formed from a resilient material of relatively low thermal conductivity which collar is sized to accommodate the body of the stethoscope head onto which it is fitted by frictional engagement with the body and has a peripheral rim extending beyond the bell to provide a deformable surface for contacting a subject to be examined, the said collar being stabilised for such use at least in part by having a surface remote from said rim in abutment with the diaphragm mounting.

9. A stethoscope head according to claim 8 wherein the said collar is stabilised by having a surface remote from said rim in abutment with the diaphragm mounting and the stem.

STATEMENT UNDER ARTICLE 19

US PATENT No. 4 995 473 (Packard) This reference provides a stethoscope head adaptor for a diaphragm microphone which is wholly unsuited for use on a bell microphone which has an open-ended air column. Claim 1 as amended is not directed to a collar in contact only with a diaphragm mounting but to one which friction fits to the body of the stethoscope head, and is stabilised by contact with the stem of a stethoscope head. The cited adaptor does not contact the body of the head. New claim 8 is directed to a stethoscope head of the bell type modified by the presence of the collar such as claimed in amended claim 1. New claim 9 is dependent on new claim 8 and relates to stabilisation of the collar by abutment with both the diaphragm mounting and the stem.

- US PATENT No. 3 366 198 (Littman) The circular construction of the "cover" of the Littman patent is entirely stabilised and dependent upon the rim of the bell, and its robustness depends on the metal of the bell. The amended claims clearly distinguish therefrom by requiring the stabilisation to occur remote from the rim of the bell. Thus the integrity of the claimed accessory would not be compromised if the bell of a stethoscope head lacked adequate intrinsic structural strength. A highly deformable cover material if used in Littman's proposal would soon loosen in use and fail the intended purpose. In contrast to that the structural stability of the invention as defined in the amended claims of this application permits use of highly deformable materials to obtain close conformity with the skin to avoid loss of sound emanating from a patient whilst excluding external sound interference.