Microphone Shock-mounting Apparatus

Abstract

Apparatus for shock-mounting a microphone comprising a compact, resilient mounting member defining a socket adapted to receive a microphone body and means for supporting the mounting member in a desired position. The mounting member defines an enclosed space encircling the socket that is preferably filled with a fluid, such as a liquid or pressurized gas. The action of the shock mount can be modified by the selection of different viscosity gases or liquids, or by the addition of foam to affect viscous damping and thereby permit tuning of the apparatus for a particular application.

Description

BACKGROUND OF THE INVENTION

This invention relates to shock-mounting apparatus, and is more specifically directed to apparatus for shock-mounting a microphone.

Those skilled in the art will appreciate that microphones with improved sensitivity and response characteristics are continually being developed by the audio industry. However, before these improved microphones can be used to best advantage, they must be thoroughly isolated from the surrounding environment by appropriate mounting apparatus. Failure to properly mount these microphones results in the transmission of structure borne vibrations to the microphone body which, in turn, creates undesired noise signals in the electrical output of the microphone.

Although methods of shock-mounting microphones have been developed in the past, each has exhibited deficiencies that have limited its usefulness. For example, a conventional so called "rubber band" type suspension system fails to provide satisfactory isolation for a microphone connected thereto, and is relatively cumbersome to assemble and use. In addition, this type of suspension system is relatively expensive to manufacture and properly install. Still further, prior mounts characteristically were undesirably large in size, which often resulted in their being within the range of a television camera or in casting shadows in the television picture. The small size of this suspension virtually eliminates any obstructions around the microphone which might interfere with the sound path or might cause unwanted sound diffraction patterns or wind noise in the area of the microphone.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies of the prior art, the present invention, in principal aspect, basically comprises a resilient mounting member that defines a socket adapted to receive the body of a microphone. The mounting member is constructed in such a way that an enclosed, shock-absorbing space encircles the socket. Means for supporting the mounting member in a desired position are also provided.

By fabricating the mounting member from an appropriate resilient material, such as rubber, and by filling the enclosed space with an appropriate material, such as pressurized gas, or shock-absorbing material, the present invention provides better shock isolation than more conventional known types of microphone suspension systems. Moreover, the invention is easy to install and use, and may be employed by inexperienced personnel in connection with a microphone mounted on a boom, a floor stand, or a desk stand. When mounted in the foregoing manner, the microphone is extremely maneuverable, and may be readily relocated to provide optimum pick-up of a mobile sound source. Mounting apparatus embodying the invention is extremely economical to fabricate, and may be manufactured from resilient material that may take the form of an annulus and is sealed in an appropriate fashion in order to form an enclosed cavity which may be filled with vibration damping material.

DESCRIPTION OF THE DRAWING

These and additional advantages and features of the present invention will hereinafter appear for purposes of illustration, but not of limitation, in connection with the accompanying drawing in which like numbers refer to like parts throughout, and in which:

FIG. 1 is a perspective view of a preferred embodiment of the present invention used to mount a microphone on a desk stand;

FIG. 2 is a perspective view of a preferred embodiment of the present invention used to mount a microphone on a boom;

FIG. 3 is a top plan view of a preferred form of microphone shock-mounting apparatus made in accordance with the present invention;

FIG. 4 is a side elevational view of the apparatus shown in FIG. 3;

FIG. 5 is a cross-sectional view taken along line 5--5 of FIG. 3; and

FIG. 6 is a cross-sectional view of the apparatus in its disassembled form.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawing and particularly to FIG. 6, a preferred form of microphone shock-mounting apparatus made in accordance with the present invention includes a mounting member 10 comprising a hollow, resilient, rubber tube in the form of an annulus. In one illustrative embodiment of the invention, the tube comprises a mid-section 16 having a 3/32 inch thick side wall 18. Side Wall 18 defines a socket 58 having a longitudinal axis A, a width W, and a length L. The tube also comprises side wall sections 24 and 26 each 0.025 inches thick. Sections 24, 25 form a side wall parallel to and displaced from side wall 18 by a distance D about seven times less than length L. Side wall sections 24, 26 and side wall 18 are joined by side wall sections 29a, 29b to form a gas-filled toroidal space 60. Side wall sections 24 and 26 define identical lips 28 and 30 at opposing ends thereof. Lip 28 comprises a rim 32, an outer mating surface 34, and an inner mating surface 36 arranged as shown. Likewise, lip 30 comprises a rim 32a, an outer mating surface 34a, and an inner mating surface 36a that are identical to the like-numbered parts of lip 28.

Eight ribs shown generally by the number 38 are equally spaced 45.degree. apart, and are formed as an integral part of the inner surface of midsection 16. These ribs are sufficiently high so that if the shock mount happens to be positioned over the sound entry of the microphone, free entry to the sound entry would still be guaranteed.

Means for supporting the mounting member in its mounted position are provided by a ring member 40 and a cylindrical collar 52, both made from a rigid plastic material such as Cycolac. As shown in FIG. 6, ring member 40 comprises a cylindrical body 42 having an inner surface 43. Attached to one end of body 42 is an L-shaped flange 44 that defines a circular notch 46 and a clamping surface 47. Ring member 40 also comprises a tab 48 that defines a mounting hole 50. The tab may be used to connect the apparatus to a fixture, such as a stand or boom. As also shown in FIG. 6, collar 52 comprises a clamping surface 54, a mating surface 55, and an outer surface 56 that fits snugly inside inner surface 43 of ring member 40.

In order to assemble the mounting member into the form shown in FIG. 5, one end of the tube is fitted through the center opening in ring member 40 (i.e., the tube is lowered into the ring member as viewed in FIG. 6). When the tube is in the proper position, inner mating surface 36a has a flush fit against clamping surface 47, and rim 32a fits into notch 46 as shown in FIG. 5. Collar 52 is then fitted between ring member 40 and side wall 24 of member 10 until it attains the position shown in FIG. 5. When the collar is properly installed, rim 32 fits against mating surface 55, and inner mating surface 36 fits against clamping surface 54.

If a permanent connection is desired, an appropriate rubber cement or adhesive may be applied to the co-mating surfaces of member 10, ring member 40, and collar 52 before the parts are assembled. The unique shape of member 10, ring member 40, and collar 52 insures a positive seal between the parts and facilitates assembly. Moreover, the location of ring member 40 adjacent the periphery of member 10 and along its midsection helps to eliminate shock occurring along any axis.

When the apparatus is properly assembled, as shown in FIGS. 3, 4 and 5, member 10 defines a socket 58 that is adapted to receive the body of a microphone. Socket 58 has a width W that is over four times as great as the distance D between sections 24, 26 and side wall 18.

Member 10 also defines enclosed annular space 60 that encircles socket 58 and which is filled with an appropriate shock-absorbing material, such as a liquid or a pressurized gas. Gas may be admitted to the enclosed space by means of a hypodermic needle, and the hole left by the needle (after it is withdrawn) may be sealed by any appropriate rubber cement or adhesive. Applicant has found in one illustrative embodiment that best results are achieved when the space is inflated to a pressure of about 1/4 to 1/2 pounds per square inch, although it will readily be appreciated that these exemplary pressure ranges may vary to best suit a particular environment. Liquid may be placed in the enclosed space by the same means.

As shown in FIG. 1, the apparatus of the preferred embodiment may be used to shock mount a microphone 65 by placing its body 64 through socket 58, and by connecting tab portion 48 to a desk mount 66.

Likewise, according to FIG. 2, the microphone may be mounted in a similar manner by attaching tab portion 48 to a boom fitting 68.

When a microphone is used in connection with the apparatus described herein, it is thoroughly insulated from structure borne vibrations and may be assembled and maneuvered in more than one degree of freedom with a convenience and reliability heretofore unattainable. It further will be appreciated that the action of the shock mount may be modified, as desired, by the choice of different viscosity gases or liquids, or by the addition of another vibration damping material, such as foam, to affect the viscous damping. This allows the apparatus to effectively be tuned for a particular application.

Those skilled in the art will recognize that the apparatus shown herein may be altered and changed without departing from the true spirit and scope of the invention.

Claims

What is claimed is:

1. Apparatus for shock-mounting a microphone having a body, said apparatus comprising:

a resilient cylindrical first side wall defining a socket adapted to receive said microphone body;

a resilient cylindrical second side wall parallel to and displaced from the first side wall, said second side wall comprising a first section terminating in a first L-shaped lip portion and a second section terminating in a second L-shaped lip portion that abuts the first L-shaped lip portion;

a third side wall connecting one end of the first and second side walls;

a fourth side wall connecting an opposite end of the first and second side walls so that the first, second, third and fourth side walls define an enclosed, toroidal, fluid-filled space; and

means for holding together the first and second L-shaped lip portions in abutting relationship, whereby the gas-filled space is sealed and said side walls are supported in a desired position.

2. Apparatus, as claimed in claim 1, wherein said means comprises a ring-shaped member adapted to comate with the L-shaped lip portions of the first and second sections.