Auscultation instrument for rendering slight sounds more audible / [August Evens].

  • Evens, August.
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: Auscultation instrument for rendering slight sounds more audible / [August Evens]. Source: Wellcome Collection.

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    AMENDED SPECIFICATION. This Print is in accordance with the Original Specification as it stands after Amendment (under Section 11 of the Patents, &e., Act, 1883), as required by the decision of the Law Officer of the 27th day of April 1897. A.D. 1890 Date of Application, 4th Aug., 1896—Accepted, 5th Sept., 1896 COMPLETE SPECIFICATION (AMENDED). Auscultation Instrument for Rendering Slight Sounds More Audible. I, August Evens of 13 Maulbeerplantage, Kassel in the Empire of Germany, Manufacturer do herebv declare the nature of this invention and in what manner */ the same is to be performed to be particularly described and ascertained in and by the following statement:— 5 This invention relates to a device for detecting the sound of movements going on in the human body or within any solid substance. The invention consists, sub¬ stantially in the covering with a membrane of any elastic substance, susceptible to the vibration of sound waves, of the opening of a hollow body, the walls ol which are very thin, the said body having an outer casing, so that between the exterior 10 and interior walls there will be a hollow space, which hollow space is made either void of air or to contain only very rarefied air. If now such an instrument is laid with its membrane against or upon a body within which a sound, however slight, is being produced, the membrane will be affected thereby and made to vibrate in connection with the interior or hollow space which 15 it covers, while the space on the other side of the cavity, which contains only rarefied air or no air at all, is either not affected by such vibration, or participates in it only to a very small extent. The vibration of the membrane may be made audible by any suitable means, as may be preferred, for example by a microphone, or a transmission of the air-vibrations proceeding from the membrane. 20 A device of the kind above described is represented in the accompanying drawing. Fig. 1 is a top-view of the back or bottom of the instrument. Fig. 2 a transverse section through the same and Fig. 3 a side view' of the same. 25 The whole device is formed of a hollow light box of small dimensions and having very thin walls. The front side of this box S is depressed to form a cavity e, the opening of which is covered by a membrane m, composed of ebonite, or vulcanite, or same similar substance. The membrane m is fastened to the edge ot the depression or cavity. Over the membrane m is a somewhat thicker plate p ot the 30 same material, fastened to the box by a ring d which is retained by a button / engaging in an elbow'ed groove fl of the ring. In the middle of this plate p, a small hole is cut in which a metal, wood or ebonite rod h is screwed or otherwise made secure (see dotted line in Fig. 2). This rod h which is made of two sections, when not in use, may be secured at the back of the box in the sockets n. On the 3 3 rear side of the box S are two openings, the mouths of two pipes g, which are connected with the cavity or hollow space e. To these pipes g, two flexible tubes Jc can be attached. The space between the walls and the outer casing of the box S is to be as void of air as possible, or the air must be rarefied. [Price 8cL]