Devices for generating acoustic waves in a liquid medium

[57] ABSTRACT

Device for generating acoustic waves in a liquid medium by implosion having two movable rigid members interconnected by a deformable membrane the membrane is formed of two annular strips each perpendicularly secured to the external edge of a movable member and to an annular flange external to the moveable members respectively to form a tight enclosure between the moveable member. At least one annular boss is provided on the external edges of the rigid members and on the annular flange to achieve a proper sealing between the external liquid medium and the enclosure.

Claims, 2 Drawing Figures

<img file="US3792425A_D0001.tif" />

PAWED FEB 121974

3,792,425

FIG.I

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87 6b 88 85 89 2b

FIG. 2

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87 6b 88 85 89 2b

3,792,425

DEVICES FOR GENERATING ACOUSTIC WAVES IN A LIQUID MEDIUM

This invention relates to improved devices for generating acoustic waves in a liquid medium, particularly by implosion.

A device of this type has been described in U.S. Pat. No. 3,564,492. It comprises a generator formed essentially of two moveable members substantially identical and opposed to each other, made of a rigid material, connected in a tight manner through an annular membrane of deformable material forming a tight enclosure with said members. This generator is provided with automatic means for moving apart said members and for starting the motion bringing them together, as well as means for locking said members in spaced relationship, and releasing means.

These members comprise at least one surface of common contact when they are brought together and are associated to means for creating inside said enclosure a lower pressure than that prevailing outside the enclosure.

According to one embodiment of the device, illustrated in FIG. 5 of the drawings of the abovementioned patent, the annular membrance connecting the moveable members may be formed of two parts, e.g. two annular strips, slightly deformable, secured to each other at their periphery and further secured to the periphery of the movable members.

The present invention relates to an improvement to said device according to which the annular membrane, also formed in two parts, is secured by means of elements which prevent an excessive deformation and a too rapid wear of said membrane.

This improvement will be now described with reference to the accompanying drawings wherein:

FIG. 1 is a cross-sectional view of the membrane and its fixation system, the device being in closed position, and

FIG. 2 is a cross-sectional view of the membrane and its fixation system, the device being in open position.

On these figures the membrane comprises two flat and annular strips 6 a, 6 b made of slightly elastic material, e.g of neoprene. Each of these strips is secured along its internal periphery to the external periphery of one of the moveable members 2 a, 2 b by means of clamping bolts 85, and along its external periphery onto an annular metal flange 86 by means of clamping bolts 87.

For conveniently distributing the stresses on the internal and external periphery of each strip, metal rings 88 are interposed between the clamping bolts and the strips. This provision avoids any deterioration of the elastic material around the bolts.

In order to achieve a good sealing between the external liquid medium and the enclosure, defined by the moveable members 2 a, 2 b in spaced position, the two membrane parts 6a, 6b and the annular flange 86, annular bosses 89 and 90 are respectively provided on the edge of members 2 a, 2 b and on the edge of the flange 86. The flexible membrane 6a, 6b being adapted to the shape of these bosses, the sealing is thus performed.

This improvement provides an increased life of use of the device and improves its power output.

From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. Consequently such changes and modifications are properly, equitably and intended to be within the full range of equivalence of the following claims.