US 2407731 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
RECEIVER EAR PIECE Fil ed Nov. 29, 1944 3* 7 uvmvron J ALBERT E.WO0DRUFF M 6.14
Arromr Patented Sept. 17, 1946 RECEIVER EAR PIEGE Albert E. Woodruff, Oak
Park, 111., assignor to 7 Automatic Electric Laboratories, Inc., Chicago,
111., a corporation of Delaware Application November 29, 1944, Serial No. 565,640
The present invention relates to improvements in earpieces for sound receivers of the type used in radio and telephone apparatus.
An important object of the invention is the provision of an improved head engaging member adapted to be detachably aflixed to a telephone or radio receiver, whereby the receiver may be maintained in efficient working relationship to the ear of a person without physical discomfort to the wearer. A further object is the provision of a comfortable and efficient ear piece which excludes from the ear of the user all sounds other than those issuing from the receiver, thereby to eliminate confusing extraneous noises.
According to one feature of the invention, a cavity for receiving the whole ear of the user is provided, the rim of this cavity engaging the bony part of the head surrounding the car so that the sound receiver is held against the users car without exerting any material pressure upon the ear itself. According to another feature, the rim of the cavity is formed as a hollow bead of flexible material slotted in a novel way to make the earpiece seat more comfortably upon the wearers head, thus to support the receiver and at the same time close the cavity to extraneous sounds. Another feature resides in the arrangement for securing the earpiece to the receiver.
,Other objects and features will be apparent from the following description taken in connection with the accompanying drawing, wherein Fig. 1 is a front elevation of the receiver and earpiece,
Fig. 2 is a rear elevation of the receiver and earpiece, 35
Fig. 3 is a view partly in cross section taken along the line 3-3 of Fig. 1,
Fig. 4 is a view partly in cross section taken along the line 4-4 of Fig. 1,
Fig. 5 is a cross section taken along the line 40 5-5 of Fig. 2, showing the application of the improved earpiece to the head of a user, and
Fig. 6 is an enlarged cross sectional view, showing a detail of the earpiece construction.
The improved earpiece is formed of rubber or like flexible material, and is so shaped as to be symmetrical with respect to the plane indicated by line 5-5 of Fig. 2. It may be secured to the associated receiver It] in any suitable manner, the preferred arrangement, however, being to provide on the receiver an outwardly extending flange or rim l l which fits tightly into an annular groove l2 in the earpiece. The rear wall of the groove preferably is reinforced as shown in Fig. 6, by molding into the rubber a metal ring l3 of L- 55 shaped cross section. If this is done the earpiece may be attached to the receiver by passing the rear portion of the receiver. through the central opening in the earpiece from the front side of the earpiece toward the back, and then temporarily distorting the front Wall of groove [2 by bending or stretching the earpiece in order to permit flange H to be forced into the groove. When the flange is properly positioned in the groove, 2. metal retaining ring I4 is secured to the receiver by four screws l5, as shown, making it impossible for the earpiece thereafter to be loosened or detached from the receiver by accident.
As thus assembled, the face 16 of the receiver is flush with the inner front face I! of the earpiece, and together these form the bottom of the cavity into which the ear of the user is placed. The rim 18 of the cavity engages the head of the user about his ear, the line of contact therebetween being generally oval in shape with the major axis of the oval extending longitudinally of the ear of the user. As best seen in Fig. 5, the contact surface of rim l8 lies in a plane oblique to the bottom of the cavity, whereby the cavity is deepest in the region behind the wearers ear and shallowest in the region forward of the ear. This brings the face of the receiver snugly into contact with the wearers ear and insures that the sounds issuing from the orifices l9 of the receiver will be projected directly into the auditory canal, while at the same time it avoids subjecting any part of the ear to such pressure as might lead to discomfort.
The rim 18 takes the form of a hollow annular bead whose outermost wall is severed by an opening 20 which extends as a continuous slot around the outer margin of the rim. This gives the rim a somewhat c-shaped cross section. As shown in Figs. 3-5, the slot 2!! does not enter the bead l8 along a line radial to the bead, but along a line which makes one side of the slot tangent to the interior circular wall of the bead.
When the earpiece is applied to the head of the user, the bead I8 will yield readily at any particular point of contact until the slot 29 becomes closed at that point; then, due to the outer free edge of the bead being reinforced by the wall which it now abuts, it yields much less readily and hence transmits more of the applied pressure to the adjacent wall section 2| which will then also begin to yield. It will be noted that the wall 2[ is considerably thicker than the Wall of the bead l8, whereby very little deformation occurs in wall 2| before slot 20 is closed. The initial yielding of bead I8 automatically adjusts the earpiece to irregularities along the line of contact with the wearers head, whereby a, substantially enclosed chamber is formed which excludes extraneous noises from the wearers ear. A small hole 22 is provided in wall 2| to equalize the pressure of the air inside and outside this chamber.
The unit may be held against the wearers head by any suitable means, this forming no part of the invention. The resultant pressure applied to the ear of the wearer will be very small, while that borne by his head is so well distributed that no discomfort can result. 7
Having described the invention, what is considered new and is desired to be protected by Letters Patent is set forth in the followingclaims.
What is claimed is:
1. In an earpiece for receivers of the class described, a body of flexible material including a hollow bead encircling the ear of the wearer so that one face of said bead engages the wearers head, and an annular slot in the outer peripheral wall of said bead whereby the head-engaging face of said bead is supported solely by the inner pe- 0 ripheral wall of said bead.
2. In an earpiece for a sound receiver, a com- 4 partment into which the ear of the wearer is adapted to be placed to bring it into juxtaposition with the receiver, said compartment including a hollow annular bead of flexible material engaging the head of the wearer, an opening in said bead such that every cross section of the bead taken along a plane radial to the axis of said receiver is C-shaped, and said opening being so disposed in said bead that the yielding of said bead when it engages the head of the wearer tends to close said opening.
3. In an earpiece for a sound receiver, a compartment into which the ear of the wearer is adapted to be placed to bring it into juxtaposition with the'receiver, said compartment including a hollow annular bead engaging the head of the wearer around his ear, an opening in said head whereby every cross section of the bead taken along a'planeradial to the axis of said receiver is C-shaped, with the open side of'the C facing directly away from the axis of the receiver.
4. An earpiece as claimed in claim 3, wherein the walls of said compartment which are adjacent to said flexible bead are also flexible but to a lesser degree than said bead.
ALBERT E. WOODRUFF.