US 3457565 A
Description (OCR text may contain errors)
July 29, 1969 J. N. SIMPSON ETAL 3,457,565
CIRCUMAURAL EAR PROTECTOR Y 2 Sheets-Sheet 1 Filed Aug. 11, 1966 Fig.4
I INVENTORS, JACK N. SIMPSON y CHARLES J. BOYER ATTORNEY 2 Sheets-Sheet 2 INVENTORS JACK N. SIMPSON CHARLES J. BUYER ATTORNEY July 29, 1969 J. N. SIMPSON ETAL CIRCUMAURAL EAR PROTECTOR Filed Aug. 11, 1966 United States Patent 3,457,565 CIRCUMAURAL EAR PROTECTOR Jack N. Simpson and Charles J. Boyer, Reading, Pa., assignors to ESB Incorporated, a corporation of Delaware Filed Aug. 11, 1966, Ser. No. 571,897 Int. Cl. A41d 21/00 US. Cl. 2--209 4 Claims ABSTRACT OF THE DISCLOSURE A circumaural, noise suppressing, pair of ear cups adjustably attached by cam operating levers to the ends of a nape strap so that upon rotation of the individual levers, the angularity and distance apart of the ear cups will change. Each lever turns an annular element having an angularly disposed groove in which an end ring at the extremity of the nape strap is inserted.
This invention relates, generally, to a noise attenuating device and, more particularly, to a circumaural ear protector to provide protection against loud noises accompanying industrial machinery, jet aircraft and the like.
An outstanding disadvantage of ear protectors commonly used for suppressing noise by the use of ear cups mounted on the ends of a headband is that the ear cups do not always fit, or fit comfortably against the earsurrounding portions of the head of the wearer, therefore cause not only discomfort but decrease the efiiciency of the ear cup seal against the head of the wearer.
An object of our invention is to provide a novel circumaural ear protector and nape strap assembly, somewhat in the form of a headset, which will overcome the abovenamed disadvantages.
A more specific object of our invention is to provide an ear protector, for suppressing noise, comprising a pair of ear cups adjustably mounted with relation to the ends of a nape strap for adjusting the angle of the cups with respect to the ends of the nape strap so as to provide a comfortable fit on varying head sizes of different wearers.
Other objects of the invention will become more apparent from a study of the following description taken with the accompanying drawing wherein:
FIG. 1 is a perspective view of a circumaural ear protector having a nape strap and adjustable means embodying the present invention;
FIG. 2 is a top view thereof showing, in dash and dot outline, a range of adjustability of the ear cups relative to the nape strap;
FIG. 3 is a rear view of the nape strap alone and of the adjusting means shown in FIGS. 1 and 2;
FIG. 4 is an enlarged plan view of the adjustment lever 4 shown in FIGS. 1, 2 and 3;
FIG. 5 is a side view of the adjustment lever;
FIG. 6 is a cross-sectional view taken along line VIVI of FIG. 4;
FIG. 7 is an exploded view showing the various parts of the left ear cup assembly; and
FIG. 8 is a vertical, cross-sectional view through one of the ear cup assemblies.
Referring more particularly to FIGS. 1, 2 and 3 of the drawing, numeral 1 generally denotes a circumaural ear protector embodying the present invention and comprising a pair of ear cups 2, of plastic or other suitable material, having detachably mounted on their mouth portions a fluid filled liner or cushion 25 (see FIGS. 7 and 8). The ear cups 2 are adjustably mounted, angularly, on the ends of a nape strap generally denoted by numeral 3 and comprising a substantially semi-circular "ice strip of spring metal 5, preferably covered by a plastic covering, such as a inch thick vinyl cover. The end portions 5 of the nape strap have terminals which project into a slot 11 of an adjustment lever, denoted generally by numeral 4. More specifically, the terminals of the nape strap are provided with holes which are placed in registry with the hole 10 which extends through the adjusting lever 4, as shown more clearly in FIG. 8. Integrally mounted on the adjustment lever 4 is a stepped or serrated handle portion which is adapted to being turned about machine screw 6 as an axis, which screw is screw threaded into hole 14 of a metal cup boss 13 integrally formed in the rear portion of the cup 2, as shown more clearly in FIG. 8. The base portion 12, as well as the integral handle portion of the adjustment lever 4, are preferably made of suitable plastic material.
Slot 11 may be disposed at any suitable angle with respect to the face of portion 12, preferably of the order of 20.
In operation, by grasping the serrated or stepped handle portion of the adjustment lever 4 and turning it through an angle 8 of (see FIG. 3) from the full to the dotted line position 9, a cam action is provided which permits the wearer to adjust the angle of the cups 2 relative to the nape or pressure spring 3 to suit his own head configuration and to provide a more comfortable fit. Such adjustment equalizes the cushion pressure on the head, front and back (or front to back). The central location of the boss 13 of the cup permits the cup assembly to automatically align itself, top to bottom, with the cup rotating about the axis of the machine screw 6, which screw is used to assemble the unit.
As shown in FIGS. 7 and 8, each cup 16 is provided with a spongy insert 18 therein and has mounted on the mouth-forming edge a base plate 20. The insert has a V-shaped notch to provide a somewhat convex shape as shown in FIG. 8 when its perimeter rests against inner peripheral surface 17.
The contact area provided by the base plate and cushion 24 has been narrowed at the top of the ear position. This allows the cup to be worn much lower on the head, making the possible use of safety hats, caps, bump caps, etc., in conjunction with the ear protector. The ear protector can thus be put on or removed without disturbing the head protection. Safety hats, caps, etc., can be worn in their normal position and do not need to be worn high on the head, as usually necessary to accommodate ear protection. Ring 20 of rigid plastic material is formed with a groove 21-22 which fits about the mouth portion 17 of the cup and serves as a base plate for supporting the cushion 24, which cushion is filled at 25 with a suitable fluid, such as glycerine or glycerine and water, sponge, grease, etc. An integral peripheral tab 23 is provided on cushion 24 which fits about the outer periphery of base plate 20 and the mouth 17 of cup 2 to form a seal. The lip is large enough to retain the ring 22 without using an elastic element, such as an O ring.
The base plate, cushion and sponge cup insert are interchangeable from left to right hand. However, the cups and adjustment levers are either right or left handed.
Moreover, adjustments can be made without the use of tools and while the ear protector is being worn.
Thus it will be seen that we have provided an efficient circumaural ear protector and nape strap assembly of such construction that the ear cups may be very easily adjusted .angularly with respect to the nape strap by a slight turn of an adjustment lever forming a component part of the ear cup to suit different head configurations and sizes; furthermore, we have provided adjusting means for a headset type of ear protector for equalizing cushion pressure on the head and for adjusting the snrina Patented July 29, 1969 pressure and the angle of the cups to suit not only the wearers own head configuration, but to provide a considerable amount of comfort in wear.
We claim: a
1. A circumaural noise suppressing device comprising a pair of ear cups of substantially oval shape having liners about the mouth portions thereof for forming a tight fit about the ears of the wearer, a nape strap bent into substantially semi-circular shape in a plane substantially at right angles to the longitudinal axes of said cups, and adjusting means mounted on said ear cups and cooperating with the ends of said nape strap and including cam means operated by rotatable outwardly projecting levers for angularly adjusting the ear cups relative to the terminal portions of the nape strap so as to fit different head configurations and sizes of wearers.
2. A circumaural ear protector as recited in claim 1 wherein said adjusting means comprises an annular element which is rotatable about an axis parallel to said longitudinal axis of the corresponding cup and which has a slot angularly disposed relative to said axis, and wherein said ends of said nape strap cooperate with said slot and are moved by cam action thereby in a manner so as to change the angle of the cup relative to the corresponding end portion of the nape strap.
3. A circumaural ear protector as recited in claim 1 wherein each of said ear cups is provided with a boss having a screw threaded opening, an adjustment lever means comprising a base portion having a central hole in registry with said opening and having a slot at an angle of the order of 20 with respect to a plane perpendicular to the axis of said opening into which the ends of said nape strap project, a machine screw extending through said hole and threaded to said boss, said adjustment lever means also including an integral lever portion extending outwardly for rotating said base portion and, by cam action, adjusting the angle of the end of the nape strap relative to the ear cup when rotated about the axis of said machine screw.
4. A circurnaural ear protector as recited in claim 3 wherein each cup is provided with a ring-like rigid element fitted against the mouth portion of the corresponding cup, a cushion of annular shape supported on each said rigid element, and a substantially disc-shaped sponge insert bent into convex shape corresponding to but of greater radius than that of the cup with its perimeter supported against the rear surface of said rigid element.
References Cited JORDAN FRANKLIN, Primary Examiner G. H. KRIZMANICH, Assistant Examiner US. Cl. X.R. 179-156 5/ 1961 Wadsworth et al 2209