US2171173A - Sound pick-up unit - Google Patents

Description

Aug 29, 1939 F. J. coYER 2,171,173

SOUND PICK-UP UNIT Filed Deo. ll, 1936 2 Sheets-Sheet 2 In ven for Frmzfz' Jaye 7,"

Patented Aug. 29, 1939 SOUND PICK-UP UNIT Application December 11, 1936', Serial No. 115,399

2- Claims.

The present invention appertains to new and useful improvements in sound pick-up units, which are mainly designed forlocating leaks in water mains.

The principal object of the present invention is to provide a device of the character stated whereby leaks can be detected by simply amplifying the sound vibration emanating from the leaky portion of the main, and traveling through the ground.

Another important object of the invention is to provide a device which is substantially foolproof and positive acting in operation.

In the drawings:

Figure l is a fragmentary vertical sectional view through the sound locating unit.

Figure 2 represents a horizontal sectional view taken substantially on the line 3-3 of Figure 1.

Figure 3 is a plan View of the lead block.

Figure 4 is a View looking into one of the cupshaped members.

Figure 5 is a top plan View of the lead block housing.

Figure 6 represents a fragmentary side elevational view partly in section of the sound locating unit grounding engaging tip.

As shown in these drawings, the sound locating unit consists of a cylindrical shell I1 within the lower portion of which is secured the circular housing I8 of steel which has a squareshaped opening I9 at its central portion, receiving the block 20 of lead.

The top and bottom sides of the assembly consisting of the housing I8 and block 20 are concave and over these concaved sides are disposed the diaphragms 2l-22. The block of lead 25J is provided with an opening 23 therethrough and through this is disposed the bolt 24, the head at one end of the bolt engaging the diaphragm 22 while the nut at the opposite end of the bolt engages the diaphragm 2|. The bolt is in rigid engagement with the lead block.

A cup-like structure 25 is disposed into the lower portion of the shell l1 so as to define a sound chamber for the lower diaphragm 22. This cup 25 has a central opening 26 therein and is covered by a thin plate 2l.

'I'he disk 2l has a cup-like structure 28 disposed thereover to dene a sound chamber 29 for the diaphragm 2l and over this is disposed the thin plate 30 upwardly from the central portion of which extends the small tube 36 which extends through the sponge rubber disk 3l.

A pair of bracket members 32 extend upwardly from the plate 30 and support the microphone (Cl. ITL-352.7)

33 from which the conductor l extends. A sound funnel 34 extends to the microphone 33 and has its lower edge bearing against the disk 3l.

Tie bolts 35 extend through the sound boxes below and above the diaphragms 2l-22 as well as through the plates 21-39 and the brackets 32 for holding these units together in rigid assembly.

When the device is placed on the ground and there is any noise in the vicinity, such as the sound of water escaping from pipes, energy is transmitted as wave motion to the earth and the earth waves shake the device. The lead block remains comparatively motionless, and thus relative motion occurs between the case and the weight, causing the air in the cup-shaped members 25 and 28 to be compressed and ratified. The air pulsations are transmitted through the tube 30 and funnel 34 to the microphone. The conductor 6 leads to an amplier to which may be connected a loud speaker.

As is shown in Figures 1 and 6, the unit 5 has an elongated tube 36 extending from the top of its shell terminating in a solid head portion 3l to which a driving point 38 is secured by the threaded shank 39, so that when desired as when soft ground is available, the pointed end of the sound locator can be driven into the ground to catch the vibration.

While the foregoing specification sets forth the invention in specific terms, it is to be understood that numerous changes in the shape, size and materials may be resorted to without departing from the spirit and scope of the invention as claimed hereinafter.

What is claimed as new is:

l. In a device of the class described, a shell having its bottom open, a plate extending across the bottom, a vibratory block located in the shell above the plate, diaphragms extending across the upper and lower faces of the block and having their major portions spaced therefrom, a bolt connecting the block with the diaphragm, upper and lower cup-shaped members forming air chambers above and below the diaphragms, each cup-shaped member having a centrally arranged opening therein, a thin plate resting on the upper cup-shaped member and having a tubular part in communication with the upper cup-shaped member through the opening therein, a resilient member seated on the plate and surrounding the tubular part, brackets resting on the upper plate, screws connecting the brackets, the plates, the cup-shaped members, the diaphragms and the block together, a microphone supported by the brackets and a funnel having its large lower end resting on the resilient member and its small end engaging the microphone.

2. In a device of the class described, a shell having its bottom open, a thin plate extending across the opening, a steel block supported in the shell `above the plate and having a centrally arranged opening therein, a lead member fitting in the opening of the steel member, said steel member and the lead member forming a Vibratory block the upper and lower faces of which are substantially concave, upper and lower diaphragm plates extending across said faces, a central member rigidly connected with and passing through the lead member and having its ends connected with the diaphragm plates, a cupshaped member having its flanges engaging the lower diaphragm plate and resting on the firstmentioned plate and having a centrally arranged opening therein, an upper cup-shaped member having its flanges resting on the upper diaphragm plate and having a centrally arranged opening therein, a thin plate resting on the upper cupshaped member and having a centrally arranged tubular part, brackets resting on the upper thin plate, screws passing through portions of the brackets, the upper thin plate, the cupi-shaped members, the diaphragm plates, and the vibratory plate and having their lower ends connected with the first mentioned plate, a microphone supported by the brackets, a resilient member resting on the central portion of the upper thin plate and surrounding the tubular part thereof and a funnel having its largeV lower end resting on the resilient member and its upper end engaging the microphone.

FRANCIS J. COYER.

Images