WO1992014427A1

WO1992014427A1 - Instrument for insertion of a plug into the ear canal

Info

Publication number: WO1992014427A1
Application number: PCT/SE1992/000097
Authority: WO
Inventors: Alf Ivarsson
Original assignee: Alf Ivarsson; Bennrup Sigrid
Priority date: 1991-02-14
Filing date: 1992-02-14
Publication date: 1992-09-03
Also published as: SE9100451D0

Abstract

Instrument for insertion and orientation of an ear plug, comprising a cylinder (10) open at one end thereof and having a circular cylindrical cylinder bore, and a piston (16) to be reciprocated in the cylinder bore, said piston having a piston rod (17) projecting from the other end of the cylinder. At said one end to be engaged with the opening of the ear canal the cylinder forms an ear-anatomically adjusted end portion (14) the exterior shape of which deviates from the circular shape.

Description

TITLE OF INVENTION: INSTRUMENT FOR INSERTION OF A PLUG

INTO THE EAR CANAL

5 Plugs for noise attenuation (hearing protectors) usually consist of an essentially circular-cylindrical plug of foamed polymeric material and are today considered as the most comfortable and effective hearing protector. Investigations have shown that the ear canal,

10 including its opening portion, seldom is round (circular) . When determining the anatomy of the ear canal, the size of the external ear canal has been measured on ear canal castings of the type produced for use in the manufacture of ear canal inserts for hearing aids, and by guidance of the

15 measurements it has been established that the opening of the ear canal of 95 % of all measured ear canals (ear canal castings) is slit-formed or oval.

On the basis of these results, it has been suggested previously in WO 91/02504 to make the ear plug with a

20 portion insertable into the ear canal, which has an oval cross secional shape, thereby avoiding annoying pressure in the ear canal.

In practice, it has become apparent that the ear plugs are not always inserted in the right way. Both hands

25 have to be used when inserting the plugs, and it is then difficult to control how the insertion is made. The plug is not always compressed enough and when compressed, it can often be contaminated with an accompanying risk of the plug causing irritation and/or inflammation in the ear canal.

30 In this connection, it is important that the ear plug

* extends over about the external half of the ear canal and * does not protrude more or less therefrom. It is also ; important that the ear plug tightly engages the wall of the ear canal after expansion in order that maximal attenuation

35 of noise coming from the outside will be achieved. In case of an ear plug with an oval cross section this means that the plug must be correctly oriented in relation to the slit-shaped or oval opening of the ear canal.

Thus, it is also suggested in WO 91/02504 in connection with ear plugs to use an instrument for the insertion of a self-expanding plug into the ear canal, but then the anatomy of the opening of the ear canal has not been considered. Even if one has realized the importance of the ear plug being tightly adjusted to the wall of the ear canal in order not to give annoying pressure, one has not realized the importance of the instrument for insertion of the plug into the ear canal being adjusted to the anatomy of the opening of the ear canal in order that the plug in a portion which is oriented correctly in relation to the opening of the ear canal will be able to pass unimpededly from the instrument into the ear canal without being pressed against portions of the ear canal at the opening thereof, which inhibits or arrests the movement of the plug into the ear canal. In other words, the plug has to be directed from the instrument straight into the ear canal. In CH-A-186 674 a device has been proposed having an externally and internally circular cylinder with a piston displaceable therein for insertion of a padding plug into a body cavity.

In order to eliminate the problems mentioned above it is proposed according to the invention an improved instrument for insertion of a self-expanding plug into the ear canal as defined in claim 1.

For further explanation of the invention reference is made to the accompanying drawings in which FIG 1 is a side view, partially an axial cross sectional view, of the instrument according to the invention,

FIG 2 is an end view of the end portion of the instrument adjusted anatomically to the ear, FIG 3 is a perspective view of an ear plug for noise r attenuation,

FIG 4 is a perspective view which illustrates the engagement of the instrument against the opening of the ear canal, 5 FIG 5 is a side view, partially an axial cross sectional view, of an instrument for insertion of an ear plug, which is provided with an angled tube passing therethrough, and

FIG 6 is a perspective view partly broken of an ear 10 plug with a central tube passing therethrough.

The instrument shown in FIG 1 comprises a cylinder 10 having a circular-cylindrical cylinder bore which at one end is sealed by an end cover 11 forming projecting finger grips 12, and which at the other end is open at 13. The 15 last mentioned end has an end portion 14 anatomically adjusted to the ear, the outer cross sectional shape of said portion being oval in order not to give unpleasant feelings when the instrument is engaged with the opening of the ear canal, due to a small and uneven contact surface, 20 as in case of the instrument with an externally circular end portion. Preferably, the exterior oval cross sectional shape of the end portion should have a major axis with a length between 3 and 10 mm. The ratio between the length of the minor axis and the major axis of the exterior oval 25 cross section should range from 0.3 to 0.95. Alternatively, the end portion can be arranged as a separate element which is demountably attached to the cylinder 10.

On the outside of the cylinder (or the separate element, respectively) a stop lug 15 is provided which is * 30 arranged at the lower part of the cylinder for engagement * against the lower part of the opening of the ear canal in i order to restrict the insertion depth of the instrument.

However, the lug can also be arranged at another place on the circumference of the cylinder, and more than one lug 35 may be present. A piston 16 having a piston rod 17 is provided to be reciprocated axially in the cylinder.

The piston rod extends through the end cover 11 and is provided at the outer end thereof with a head 18 so that the instrument can be grasped with a pair of fingers around the finger supports 12 and, with the thumb engaged against the head 18, the piston 16 can be displaced through the cylinder towards the open end thereof, see FIG 4.

In FIG 1 a self-expanding plug 19 of foamed polymeric material is shown which is inserted into the cylinder in a compressed state. After the end portion 14 of the instrument has been engaged against the opening of the ear canal this plug can be pushed unimpededly into the ear canal by the piston 16 being displaced through the cylinder pressing out the plug therefrom, see FIG 4. The piston rod 17 is provided with a tap 20 which slides in a slot 21 in the cylinder 10 in order to restrict the insertion depth of the plug. The plug 19, see FIG 3, can have a circular or elliptic cross section and can be cylindrical, e.g. in case of punched or extruded plugs, or slightly conical, e.g. in case of injection moulded plugs (for relief). Also plugs of fine glass wool or plugs provided with flanges can be used in connection with the instrument according to the invention.

The cylinder 10 can be provided with a longitudinal slot 22, see FIG 5, extending axially a part inwards from the open end, in order to be used in connection with an ear plug 23 according to FIG 6, which consists of foamed polymeric material with a central tube 24 passing therethrough and otherwise can be designed as the plug 19. The tube 24 can be straight, have an angled portion or be connected to, for example, an angled connector tubing 25, and instead of a tube an acoustically tight pin can be provided which facilitates the removal from the ear canal. In FIG 5 the plug 23 is shown inserted into the cylinder 10, the angled connector tubing 25 connected to the tube 24 being received by the slot 22. When displacing the piston 16 through the cylinder the plug 23 being pressed out therefrom, the connector tubing slides in the longitudinal slot of the cylinder. The plugs 19 and 23 can, of course, be used in connection with instruments with or without a slot, the length of the piston stroke being adjusted to the plug so that the piston cannot be displaced longer than the plug having just left the cylinder. By the end portion of the instrument having the same cross sectional shape as the opening of the ear canal an optimal direction of introduction is achieved since the shape of the end portion enables application of the instrument close to the straight front wall of tragus, which is a prerequisite for the instrument to be centered on the centre of the opening of the ear canal.

Moreover, an ear-anatomically adjusted end portion provides the advantage that the instrument, when engaged against the opening of the ear canal, assumes the same angle as the ear canal, i.e. slightly uppwards/inwards. An optimal direction and orientation of the ear plug is achieved thereby in order to properly position the plug in the ear canal, sealingly engaging the bounding walls thereof, so that the ear plug will effectively prevent environmental sound from entering the ear canal.

Furthermore, the shape of the end portion allows deep engagement in the bowl-shaped opening of the ear canal, the stop lug 15 restricting the insertion depth, which additionally improves the chance of correct orientation of the plug in the ear canal.

The instrument can be designed with different diameters of the cylinder 10 in order to fit ear canals of different sizes.

It is obvious that the instrument according to the invention can be used for insertion of self-expanding plugs irrespective of what cross sectional shape they have, but it is an advantage to be able to use the instrument especially for plugs with an oval cross sectional shape considering that such plugs are best adjusted to the shape of the ear canal of most people. Then the end portion 14 (or the separate element, respectively) should also have an internally oval or elliptic cross sectional shape adjusted to the cross sectional shape of the ear plug.

Claims

1. Instrument for insertion and orientation of an ear plug, comprising a cylinder open at one end thereof and having a circular cylindrical cylinder bore, and a piston to be reciprocated in the cylinder bore, said piston having a piston rod projecting from the other end of the cylinder, c h a r a c t e r i z e d in that the cylinder at said one end to be engaged with the opening of the ear canal forms an ear-anatomically adjusted end portion, the exterior shape of which deviates from the circular shape.

2. Instrument as claimed in claim 1, c h a r a c ¬ t e r i z e d in that the interior shape of the end portion differs from the circular form.

3. Instrument as claimed in any of claims 1 or 2, c h a r a c t e r i z e d in that the interior and/or exterior shape of the end portion has an oval cross sectional shape.

4. Instrument as claimed in any of claims 1-3, c h a r a c t e r i z e d in that the major axis of the exterior oval cross section has a length between 6 and 15 mm, the minor axis thereof having a length between 3 and 10 mm.

5. Instrument as claimed in any of claims 1-4, c h a r a c t e r i z e d in that the ratio between the lengths of the minor and major axes of the exterior oval cross section lies between 0.3 and 0.95.

6. Instrument as claimed in any of claims 1-5, c h a r a c t e r i z e d in that said one end for engagement against the opening of the ear canal is provided with a stop lug in order to restrict the insertion of said end into the opening of the ear canal.

7. Instrument as claimed in any of claims 1-6, c h a r a c t e r i z e d in that said stop lug is arranged at the lower part of said one end for engagement against the opening of the ear canal.

8. Instrument as claimed in any of claims 1-7, c h a r a c t e r i z e d in that said cylinder has a longitudinal slot for receiving a connector tubing or the like angled from the ear plug angled .

9. Instrument as claimed in any of claims 1-8, c h a r a c t e r i z e d in that the stroke of the piston rod is restricted.