US 3314424 A
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Description (OCR text may contain errors)
p 1967 M. BERMAN 3,314,424
MICROPHONE SUPPORT DEVICE FOR A MASK Filed Nov. 14, 1962 2 Sheets-Sheet 1 a m ns/vraz MAXVMFAA 552/144 April 18, 1967 M. BERMAN 3,314,424
MICROPHONE SUPPORT DEVICE FOR A MASK Filed Nov. 14, 1962 2 Sheets-Sheet 2 a 4 54 54a 54 Ami/mm 555511545555 MMHMMHM/I 1:1 l 5fl mmammm United States Patent 3 314,424 MICROPHONE SUPPRT DEVICE FOR A MASK Maxwell Berman, Los Angeles, Calif, assignor to Douglas Aircraft Company, Inc., Santa Monica, Calif. Filed Nov. 14, 1962, Ser. No. 237,587 2 Claims. (Cl. 128-1424) My present invention relates generally to support devices and more particularly to a means and method for providing a flexible support which is easily adjustable over a wide range but which remains firmly fixed in position after it is adjusted. This invention is especially useful in a small confined space as normally encountered within a mask or helmet between a transparent face plate and the face of a person wearing the mask or helmet.
In fighting fires, smoke masks are usually worn by the fire fighters when working in close proximity to the body of a fire. These masks are designed to be compact and lightweight such that there is very little space left between the glass face plate of the mask and the face of the person wearing the mask. In order to make satisfactory communication possible between the fire fighters, each fire fighter can be provided with a microphone, voice amplifier and loudspeaker. The microphone, of course, must be mounted within the mask before the weare-rs mouth, and is normally connected to the amplifier by an electrical cable. The amplifier and the loudspeaker which is driven by the output of the amplifier can be carried by the fire fighter outside the mask on the persons body, or integrally mounted on the mask if a small amplifier and loudspeaker are used.
Because of the very limited space left within a mask, and because of the wide differences in sizes of the heads and the variations in contour of the faces of various individuals who will wear these masks, it is quite a problem to provide a satisfactory support device for the microphone wherein the support device is small and compact but which is, however, easily adjust-able to position the microphone accurately and fixedly, directly before the individuals mouth. This is a major problem when it is considered that a fire fighter is extremely active, making vigorous and sharp motions of the head almost continuously. Since such a person cannot be burned with a large and heavy amplifier including a large and heavy battery, the microphone must be kept accurately in close proximity and directly before the mouth of each individual who is wearing the mask.
Bearing in mind the foregoing, it is an object of my invention to provide an easily adjustable support device which is particularly useful in accurately mounting an object in a very limited space.
Another object of this invention is to provide an easily adjustable support device for use in a small, closely confined space, and which is small and lightweight but remains firmly fixed in position after it is adjusted to a desired condition.
Another object of this invention is to provide a support device for use in a small, closely confined space, and which is incongruously widely and universally adjustable in such space to substantial extents in all directions and orientations.
A further object of the invention is toprovide a relatively simple, small, lightweight and adjustable support device for use in a mask (and the like), in mounting a microphone within the mask accurately before the mouth of the wearer.
Briefly, and in general terms, the foregoing and other objects are preferably accomplished by providing, in essence, a support device comprising a relatively soft and flexible, support elongate rod or wire having suitable terminations on each end, and which is longitudinally housed 3,314,424 Patented Apr. 18, 1967 in a smoothly close fitting length of a helically wound spring. The ends of the spring are secured in substantially fixed relation to respective points near the ends of the support wire by the cooperative retaining action of the terminations which are adapted to cup or hold the spring ends.
The spring ends may be additionally secured to their respective terminations by crimping or soldering the terminations to the spring ends. In another version of my invention, the ends of the spring are welded or brazed directly to respective points or areas near the ends of the support wire without involving or contacting the terminations on the ends thereof.
My invention also includes a method involving certain sequences of various steps which may be performed by hand and/or suitable machinery. In one version of my method, the support device is produced by suitably terminating one end of a relatively soft and flexible, elongate rod or wire, longitudinally sliding a shorter length of a smoothly close fitting, helically wound spring onto the wire, bending the wire and its enclosing spring to a maximum desired curvature while maintaining the adjacent end of the spring in fixed engagement with the termination on the end of the wire, and then terminating the other end of the wire so that this termination also is in fixed engagement with the other end of the spring.
In another version of the method, the support device is produced by longitudinally sliding the shorter length of a smoothly close fitting, helically wound spring onto a relatively soft and flexible longer length of support elongate rod or wire, bonding one end of the spring to a point or area near the adjacent end of the wire, bending the wire and its enclosing spring to a maximum desired curvature, bonding the other end of the spring to a point or area near the adjacent end of the wire, and terminating the ends of the wire.
My invention will be more fully understood, and other objects and advantages thereof will become apparent from the following detailed description of specific, illustrative examples of the invention to be taken in conjunction with the attached drawings, in which:
FIGURE 1 is a sectional side elevation view of a smoke mask worn by a fire fighter and including a support device according to my invention as used to mount a microphone accurately and fixedly before the mouth of the wearer;
FIGURE 2 is a rear elevational view of the smoke masks air inlet plate to which is attached the support device showing the normal shape of the device;
FIGURE 3 is a side elevational view of a support device which is not shown bent to any particular shape, and does not include mounting means for mounting a microphone or the like;
FIGURES 4A through 4H illustrate various steps in one version of my method for producing a support device; and
FIGURES 5A through 5F illustrate various steps in another version of the method.
FIGURE 1 is a profile drawing showing a fire fighter 10 wearing a smoke mask 12 which is illustrated in section along a central, vertical plane parallel to the plane of the paper. The mask 12 is generally conventional and has a transparent face plate .14 suitably mounted in a pair of formed channel rims 16a and 16b. The normally upper rim 16a is secured on the sides to the normally lower rim 16b at the ends by screws or any suitable fasteners (not shown), in order to hold the face plate 14 fixedly between the rims 16a and 16b.
Also secured to the rims 16a and 16b is a molded rubber hood 18 shaped to fit snugly around a persons face to be airtight. The hood has two holding or locking attachments 20 on each side and one holding or locking attachment 20 on the top to which can be secured the ends of the five straps 22a of a rubber, head attachment connector piece or member 22. By drawing the straps 22a through their respective holding attachments 20, the hood 18 is drawn and held firmly against the persons face so as to be airtight.
The hood 18 is formed and shaped to provide a circular opening 24 at the normally lower end, and the circula end 26a of a housing 26 is fitted therein and secured thereto by clamp ring 28. The housing 26 houses an exhaust valve 30 in the outer end portion 26b and has a lower inlet connection 260 which connects with a filtered air inlet hose 32.
An air inlet plate 34 is molded with a widened air distribution opening 34a and a tubular extension 3413 (FIGURE 2) which communicates with the exhaust valve 30, and cooperatively forms an inlet passageway 340 between the housing 26 and the tubular extension 34b- This passageway 34c connects, of course, with the widened air distribution opening 34a. The plate 34 is attached to the housing 26 by a screw 36.
Attached to the outer end portion 26b (FIGURE 1) of the housing 26 is a communication unit 38 including an audio amplifier, loudspeaker and battery (all of which are not shown). The unit 38 is connected to a microphone 40 which is mounted within the mask 12 by an electrical cable 42 (FIGURE 2). The electrical cable 42 is passed through the rubber hood 18 of the mask 12 through a suitably sealed grommet (not shown). The unit 38 can be turned on by actuating a switch 38a located on the right side of the unit 38.
The microphone 40 is mounted on support device 44 so that it is accurately positioned near and directly before the mask wearers mouth. As can be seen in FIGURE 1, there is relatively very little available space in which to mount the microphone 40. Since the size and shape of each wearers head is widely variable for different individuals, the microphone 40 has to be adjustable over a wide range.
The microphone 40 must not be positioned too close to or too far from the wearers mouth, and it should also be located directly in line before the persons mouth. The adjustment must be fairly precise since very little variation is permitted because of the relatively small size of the unit 38. Note that there is very little existing structure to which to firmly afiix the mounting means or support device for the microphone 40. It is, of course, apparent that the very limited space available does not allow any installation of elaborate mounting structure which accurately and firmly mounts the microphone 40, and also provides a wide adjustment range therefor.
FIGURE 2 is a view of the plate 34 as seen by a person looking into the mask 12 from the rear or behind the mask as in the process of putting it on. The support device 44 is also shown normally attached on one .end to the plate 34 by use of the screw 36 which was provided originally only to secure the plate 34 to the housing 26. The other end of the support device 44 includes a clamp 46 which mounts the microphone 40. The clamp 46 is preferably a nylon loop type clamp.
The microphone 40 is a conventional device having an electrical cable 48 connected on one end to terminals on the back of the microphone 40 and an electrical receptacle 50 connected on the other end. The electrical cable 42 connecting on one end with the communication unit 38 has an electrical plug 52 connected to the other end. The plug 52, of course, engages the receptacle 50 such that the microphone 40 is electrically connected to the unit 38 through cables 48 and 42. The connected receptacle 50 and plug 52 combination is suitablyrsecured by a clamp (not shown) or can simplybe firmly held in position by the support device 44 pressing it tightly against the plate 34, as shown in FIGURE 2.
The plate 34 is molded with a front wall 34d and a rear wall 34c to provide a widened air distribution opening 34a therebetween. The plate 34 includes a tubular extension 34b which extends generally forward (from the mask wearer) of the relatively flat inner surface of wall 34e closest to the wearers face. The tubular extension 34b in co-operation with the circular end 26a of housing 26 forms the air inlet passageway 34c which connects at the inner end with the opening 34a. The outer end of the passageway 34c connects with the lower air inlet connection 260 (FIGURE 1), and the tubular extension 34b connects the inside of the mas-k .12 with an exhaust valve 30' mounted in the outer end portion 26b of the housing 26. The housing 26 and the plate 34 are both preferably fabricated of plastic.
FIGURE 3 shows a support device 44 which is not bent to any particular shape, nor does it have a mounting means (microphone clamp 46) attached to end end. The (bent) device 44 is a flexible support means comprising a soft steel elongate rod or wire 54 which is, for example, 3% inches long, size 14 A.W.G., zinc coated commercial grade E wire, .a spring 56 which is 2% inches long, 0.151 O.D., 0.025 inch diameter wire, close wound and cadmi um plated, and a pair of terminal lugs 58a and 58b which are, for example, type YAV14-G82 lugs manufactured by Burndy Corporation of Norwalk, Connecticut. The lengths given above for the elongate rod or wire 54 and spring 56 are those for a device 44 which is bent to the shape illustrated in FIGURE 2.
The elongate rod or wire 54 preferably has a circular cross section, and the spring 56 preferably ha a correspondingly circular central opening formed by circular helical turns. An elliptical cross section wire may be desirably used under certain circumstances with a suitably wound spring providing a similar elliptical opening. The elliptical cross section support device would permit bending primarily at right angles to the Wider, central longitudinal plane but restricts bending at right angles to the narrower, central longitudinal plane of the device. The wire 54 and spring 56 are preferably metallic although they can be fabricated of other materials such as bendable plastic, for example. Plastic coated metals or various mixtures can also be used.
Other cross sections of wire 54 and the cooperative, correspondingly shaped openings of the spring 56 may be used. Under certain conditions, the cross section of wire 54 may differ from the opening of the co-operative spring 56. For example, a round cross section wire 54 may be used with a spring having turns forming an elliptical opening. The round cross section wire may be necessary to accommodate certain types of termination connections, and the elliptically shaped spring restricts adjustment bending mainly at right angles to the wider central longitudinal plane of the device.
In addition, the wire 54 and spring 56 can taper gradually from one end to another, or taper gradually from a central attachment point or area gradually outward to the ends which can mount respective objects; In this instance, the broad ends of two tapering Wire and spring combinations are suitably joined together to form an integral unit. Other variations should be apparent from the foregoing.
The lugs 58a and 58b are afiixed to the ends of the flexible support means such that the planes of the flat, outer ends of the lugs are substantially at right angles to each other. This is desirable for the mounting arrangement shown in FIGURE 2 wherein the lug 58a is fastened by screw 36 in an approximately vertical plane, and the lug 58b is fastened by screw .60 and nut 62 and set in an approximately horizontal plane to the ends of the'clamp 46, substantially as shown. The support device 44 can be bent to various positions as 'desiredfrom the normal arrangement depicted in FIGURE 2.
FIGURES 4A through 46 respective show the various steps of one version of a method for producing the support device 44. The spring 56 and elongate rod or wire 54 are first cut to the necessary lengths as shown in FIGURES 4A and 4B. The ends of the cut wire 54 are flattened at the ends by either grinding or compressing by any suitable means, such that the flattened ends 54a and 54b are flattened in planes which are at right angles to each other as illustrated in FIGURE 4C. It is to be noted that the step of flattening the ends of the wire 54 is unnecessary if a copper wire was used instead of a steel one together with copper lugs 58a and 58b.
The flattened ends 54a and 54b of the wire 54 are first tinned by dipping into molten solder, and then inner (relative to the center of the lug) end of the lug 58a is crimped to the end 54a as shown in FIGURE 4D. As indicated in FIGURE 4D, the spring 56 is next slipped onto the wire 54 and the corresponding end of the spring 56 is pushed snugly into the split, outer end of the lug 58a and the split outer end of the lug 58a is crimped together as shown in FIGURE 4E to firmly hold the end of the spring 56. The split ends must not be crimped too tightly on the end of spring 56 or the spring becomes distorted.
The spring 56 and wire 54 having a terminal lug 58a attached thereto is then bent to a maximum desired curvature or shape as shown in FIGURE 4F. This shape is that in which the microphone 40 is positioned in approximately its desired, maximum curvature location beyond the normal location which is illustrated in FIGURE 2. The spring 56 and wire 54 are sufliciently long to permit bending of the flexible support to position the microphone 40 in any place over a fairly large space from the normal position shown.
When the spring 56 and wire 54 are bent to the maximum desired curvature or shape, the other unterminated end of the wire 54 is drawn farther into the spring 56 until the proper length of the end of wire 54 remains ex posed as indicated in FIGURE 4F. Terminal lug 58b is then placed onto the end of the wire 54 and pushed snugly against the corresponding end of the spring 56 within the split, outer end of the lug 58b. The inner end of the lug 58b is then crimped onto the end of the wire 54, and the split, outer end crimped firmly on the end of the spring 56 to hold it in place against all adjustments of the flexible support.
Finally, the terminated ends of the flexible support are dipped into molten solder as shown in FIGURE 4H. This dipping is preferably to a point just above the split, outer end of each lug, covering the lugs entirely. The dipped ends are flicked and wiped clean except for the crevices where solder is desired. The bent support device can then be shaped to a normal, desired curvature from its maximum curvature. This soldering of the lugs to the ends of the wire 54 and spring 56 is also unnecessary if a copper wire is used with the copper lugs 58a and 58b. The crimping of a copper lug onto a copper wire causes sufficient compression to produce self-welding between the elements.
However, a steel wire 54 lasts much longer than a copper wire, and is desirable from thi standpoint. But the use of a copper wire with the copper lugs would eliminate the steps of flattening the ends of the wire 54 (FIGURE 4C) and the last soldering step (FIGURE 4H). The soldering of the split, outer end of each lug to a corresponding end of the spring 56 is not necessary and is unimportant so long as the split, outer ends are crimped firmly on their respective spring ends.
The spring 56 prevents the wire 54 from kinking and should fit closely and smoothly on the wire 54. The ends of the spring 56 should, therefore, be restrained primarily from any lateral movement relative to the wire 54 by the spring 56, and the spring should be reasonably closely wound and sufficiently long such that significant gaps do not appear between the turns or coils when the flexible support is bent to any extent or degree. The ends of the wire 54 must be tightly secured to their respective lugs, and the ends to the spring 56 are preferably aflixed rigidly to their respective lugs although a very slight amount of longitudinal movement would not be detrimental and may under certain conditions be beneficial and desirable.
FIGURES 5A through 5F illustrate the respective steps of another version of my method for producing a flexible support device. FIGURES 5A, 5B and 5C depict steps which are identical to those of FIGURES 4A, 4B and 4C, respectively. FIGURE 5D shows the spring 56 slipped onto the elongate rod or wire 54, with the corresponding (left) end positioned near the end 54a, and then the last few turns of the end of the spring 56 are welded, brazed, soldered or otherwise bonded to a point or area on the circumferential surface of the wire 54. The other (right) end of the spring 56 is noted to be situated a greater distance from the end 54b of the wire 54 than the other spring end with respect to its corresponding end 54a.
FIGURE 5E illustrates the bending of the wire 54 and spring 56 combination to a maximum desired curvature or shape wherein the end 54b of wire 54 is drawn farther within the spring 56 so that the corresponding end of the spring 56 is located a distance from the end 54b similar to the distance that the other end of the spring 56 is located from end 54a of the wire 54. The last few turns of the end of the spring 56 corresponding to end 54b is then similarly bonded to the circumferential surface of the wire 54 just like the other bonded end.
FIGURE 5F shows the final step of terminating the ends of the bent and bonded wire 54 and spring 56. The lugs 58a and 5817 are placed onto the respective ends 54a and 54b so that the split, outer ends are snug against the corresponding ends of the spring 56. The inner end of each lug is crimped onto the corresponding end of the wire 54 and then the split, outer end is crimped on the corresponding end of the spring 56. If desired, the crimped lugs may be further dipped in molten solder as was done (FIGURE 41-1) in the previous version of the method. The maximumly bent wire 54 and spring 56 combination is subsequently adjusted to any desired shape.
As in the previous version of my method, flattening of the ends of the wire 54 is unnecessary if a copper wire was used with copper lugs. Thus, the step indicated in FIGURE 5C can be omitted in such instance. Flattening of the ends of a steel wire was found to aid in holding the lugs rigidly and firmly in place after the copper lugs were crimped onto the flattened ends of the steel wire. Obviously, various terminations other than lugs may be used as required.
Note that in the latter version of my method, the wire 54 can be shorter on one or both ends than the outer spring 56. This is indicated by dots A, B and C in FIG- URE 5F indicating various weld points. Points A and C illustrate. weld points wherein the left and right ends, re-
spectively, of the wire 54 are shorter than (located within) the corresponding ends of spring 56. Point B is a longitudinally central weld point between the wire 54 and spring 56. Such a weld point B can be employed with the wire 54 being either longer or shorter, on one end or both, than the spring 56.
While the support device is shown in FIGURE 5F as having a single bend, the central weld point B is preferably used when, say, separate bends are sequentially made between two consecutive weld points. The intermediate weld point B is unnecessary, of course, but its use does permit some tolerance in dimensions between wire diameter and spring opening diameter, or use of longer support devices having more than one bend therein. Additionally, the central weld point B can be used as the attachment point to fixed structure, and both ends of the support device can be used to mount respective objects.
My support device was found to be relatively very simple, small and extremely effective for mounting objects especially in a confined space. The device could be adjusted over a wide range of positions and could be easily attached to any structure. A single screw can be used to attach the support device to a single point on fixed structom, and the device effectively holds an object such as a microphone accurately and fixedly in position. The supported object is not held in position solely by the inner support wire or the surrounding spring alone; it is supported by the combined action of the two elements. Similarly, adjustment of the mounted object is accomplished by co-operative action of both inner wire and outer spring. The device is extremely versatile and can be adjusted to have more than one bend therein.
From the above description it will be apparent that there is thus provided a device and method of the character described, possessing the features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts or steps without departing from the principles involved or sacrificing any of its advantages.
While the invention has been described in language more or less specific as to structural features and steps, it is to be understood that my invention is not limited to the specific features and steps shown, but that the means and method herein disclosed comprise illustrative examples of several modes of putting the invention into efiect, and my invention is, therefore, claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.
1. Support means for mounting objects thereto, comprising:
an angularly bent elongated rod said rod being of a first predetermined straight length and initially bent angul-arly to predetermined maximum curvatures from an intermediate point; and
a tubular spring coil of a second predetermined straight length longitudinally positioned on said rod, having a corresponding intermediate point thereon secured in substantially fixed relationship with said intermediate point of said rod, and having two selected coil points on opposite sides of said intermediate coil point secured in substantially fixed relationship with respective, predetermined points on opposite sides of said intermediate rod point so that said coil is initially placed in predetermined, maximumly stretched conditions between said intermediate coil point and said predetermined coil points, respective- 1y, when said rod is angularly bent to said predetermined maximum curvatures,
whereby a co-operative combination is obtained for providing a flexible support means which can be fixedly adjusted to any desired normal curvatures between said relatively secured coil and rod points, less than said predetermined maximum curvatures, respectively, over a Wide angular range and to various configurations.
2. Mask means comprising:
a mask subject to frequent, vigorous and sharp motions having a very limited space for accommodating said microphone, and including attachment structure having very limited area for attaching support means for mounting said microphone in said limited space;
support means including an angularly bent wire, said wire being of a first predetermined straight length and fabricated from a relatively pliable metallic material and initially bent angularly to a predetermined maximum curvature,
a tubular spring coil of a second predetermined straight length of wire longitudinally positioned on said wire, and having coil end points secured in substantially fixed relationship with respective predetermined points near corresponding ends on said wire so that said coil is initially placed in a predetermined, maximumly stretched condition between said predetermined points when said wire is bent to said predetermined maximum curvature, and
mounting means comprising a first terminal lug secured to one end of said wire, a second terminal lug secured to the other end of said Wire, and clamp means attached to saidsecond lug for mounting said microphone,
whereby a co-operative combination is obtained for providing a flexible support means which can be fixedly adjusted to any desired normal curvature, less than said predetermined maximum curvature, over a wide angular range and to various configurations; and
means for attaching said first lug'substantially to a single point on said very limited area of said attachment structure of said mask.
References Cited by the Examiner UNITED STATES PATENTS 375,702 12/1887 Fasoldt 248 472,611 4/1892 Stanley 248-274 480,749 8/ 1892 Stanley 248-160 1,789,137 l/l931 Fitoh 29445 2,076,764 4/ 1937 Cowdery 29-505 2,353,070 7/1944 Pitkin 1'79-156 2,935,985 5/ 1960 Andrews et al 128141 RICHARD A. GAUDET, Primary Examiner.
JORDAN FRANKLIN, D. S. BURKS, W. E. KAMM,