A headphone which is usable particularly along with a plurality of other headphones includes a transducer which is connected through a switch to the source of current. The switch provides a means for automatically turning the transducer either on or off. In one embodiment the switch includes a mercury switch which when oriented in an inactive or nonoperative position, ensures that the transducer is turned off and in another position in which operation normally takes place, will ensure that the transducer is turned on. Another embodiment includes a spring operated switch control which is operated when the earphone, for example attached to a headband, is positioned on the head of a user. Such a switch may be spring actuated or may include a member which is displaceable when the resilient cushion for the earpiece of the earphone is compressed.
The present invention provides a two-way sound transducer system, including amplification circuitry within an ear-muff type attenuator, to enable the user to listen to principally voice communications (although other forms of sound can be transmitted) from a remote location and in response thereto answer a communication by talking in a natural voice, irrespective of the total surrounding noise present at the location of the user.
A stereo headphone having left and right headphone units which are connected to a binaural input plug that has left and right input cords respectively connected between the left and right headphone units and wherein the right and left input cords are connected together in parallel between the binaural input plug and a predetermined intermediate point and with a muting switching device mounted at the intermediate point so as to allow muting of both headphone units under selected conditions.
An infrared head set which is made as a chin bow receiver which is designed to pick up infrared signals and convert them into an audio transmission in the auditory range. This infrared head set includes a base housing (20a-c) and two bow ends (27) with one miniature speaker each located on the end side. The two bow ends (27) are supported in the base housing (20a-c) and can be elastically spread in at least one plane. The bow ends (27) are dynamically connected to at least one switch (5) housed in the lever action range of the plane. The switch turns on the receiving circuit for a certain spread position (12) of the bow ends (27) with the spread position (12) being dependent on wearing. Automatically turning reception on and off of the chin bow receiver dependent on wearing is advantageous. In addition, the head set contains audio management circuitry which automatically turns off when a certain audio quality is not reached and automatically turns on reception again as soon as audio transmission again has a fixed minimum quality.
A headset is provided, of a type which includes a pair of earmuff devices at opposite ends of a head band, which automatically switches an electronic circuit on or off when the headset is placed on the head or taken off, in a simple and rugged construction. Each earmuff device is of the type that includes a largely rigid housing (24, FIG. 3) and a soft resilient cushion (30) mounted on the housing and designed to receive the ear of the wearer and press against the side of the wearer's head which surrounds his ear. A switch (54) connected to the circuit includes an actuating device (60) that is depressed and released along with the cushion. One type of switch (54) is a mechanical type whose actuator device (60) has a front end lying against a rear side (64) of the cushion to be deflected and operate the switch when the cushion is rearwardly deflected during placement on the wearer's head. Another switch includes an electrically conductive element (92, FIG. 5) lying on the forward surface of the cushion to directly contact the wearer's skin, and a detect subcircuit (96) which is responsive to the electrical potential of the wearer's body to switch the electronic circuit.
In a hearing device, such as a circumaural earmuff cup or a circumaural earphone cup, either of which comprises an earpad assembly in contact with the external ear, through which sound is conducted to the external ear for the purpose of providing at the eardrum a sound pressure having a prescribed ratio with respect to the sound pressure at a source, the invention comprising a predetermined sound leakage path through said earpad assembly, to reduce the variable in said ratio, that is customarily encountered caused by the variations in the shape of the external ear from one user to another and by variations in position and force of contact of the earpad resting against the pinna.
