Abstract:
An in-the-ear hearing aid having multiple directional microphones connected to a signal processing unit. The connection of the microphones can be reversed by a selector switch to selectively switch the hearing aid between a left-ear configuration and a right-ear configuration.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a procedure for adaptively setting a hearing aid and a hearing aid. 
     The configuration of the outer capsule of hearing aids, and especially of in-the-ear hearing aids, in many cases does not take into consideration whether the hearing aid concerned is to be worn in the left or in the right ear. 
     It is thus entirely possible to manufacture uniform hearing aids regardless of whether they are to be used on the left or the right ear. 
     However, if the hearing aid in question incorporates two or more microphones, for instance in order to establish for the hearing-aid signal processing unit a particular reception pattern relative to the direction of the impinging sound wave, these microphones must be placed on or in the ear in a specific position in relation to the head; for example, for frontally received audio signals a microphone must point forward, whether it is worn on the left or on the right ear. 
     It follows that for basically uniform hearing aids, it is necessary after all to produce and handle two variations, one for the left ear and one for the right ear. This requirement is illustrated in FIG. 1 which is a schematic top view of two in-the-ear hearing aids, one for the left ear L, the other for the right ear R. As can be seen, the microphone V which serves to process audio signals received from the front and the microphone H which processes audio signals received from behind are positioned in the otherwise uniform hearing aid in mirror-image fashion. 
     It goes without saying that the resulting need to produce hearing-aid sets with different microphone configurations, respectively for left-ear devices L and right-ear devices R as shown in FIG. 1, constitutes a significant drawback. 
     BRIEF SUMMARY OF THE INVENTION 
     The basic concept employed in the hearing aid involves directional switchability of the signal-processing microphones. Accordingly, only one hearing-aid configuration need be manufactured and, preferably, it is not until an individual is fitted with a hearing aid that the desired setting between the respective microphone of the signal processing unit and, ultimately, the integrated output converter of the hearing aid, is selected by means of the appropriate switch position. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is a schematic representation of a set of hearings aids having forward and rearward microphone according to the prior art; and 
     FIG. 2 is a schematic representation of a hearing aid according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 2 is a schematic illustration of an example of a manufacturable hearing aid  1  according to this invention and of the implementation of the adaptation procedure as provided for by this invention. As indicated in FIG. 2, the hearing aid  1  according to this invention incorporates at least two microphones  3   a  and  3   b  each of which connects to an analog/digital converter  5   a ,  5   b . According to this invention, a selector switch assembly  9  with a control input S is interpositioned between the digital outputs of the analog/digital converters  5   a  and  5   b , respectively, and the inputs of a signal processing unit  7 . The switch assembly  9  permits reversal of the output of the microphones  3   a  and  3   b , respectively, relative to the inputs of the signal processing unit  7  which in turn inverts the signal for the electromechanical output converter  11  of the hearing aid  1 . This makes it possible to produce identical hearing aids, and especially in-the-ear type hearing aids, with the adaptation preferably performed when the hearing aid  1  is fitted, by setting the switch  9  so as to select forward or rearward reception of the microphone  3   a  or  3   b  and making the appropriate connection with the signal processing unit  7 . The connection to the control input S of the switch assembly  9  may be hard-wired or wireless, depending on the technology employed in the design of the product. 
     Specifically, the selector switch assembly  9  is a double pole, double throw switch. The first microphone  3   a  is connected to a first throw  9   a  of the selector switch assembly  9  through the first analog/digital converter  5   a . The second microphone  3   b  is connected to a second throw  9   b  of the selector switch assembly  9  through the second analog/digital converter  5   b . A first pole  9   c ,  9   d  of each throw  9   a ,  9   b  is connected to a forward first signal input  7   a  of the signal processing unit  7 . A second pole  9   e ,  9   f  of each throw  9   a ,  9   b  is connected to a rearward second signal input  7   b  of the signal processing unit  7 . 
     Thus, when the selector switch assembly  9  is set in a first position mode, the first microphone  3   a  is operationally connected to the forward first input  7   a  of the signal processing unit  7  and the second microphone  3   b  is operationally connected to the rearward second input  7   b  of the signal processing unit  7 . Thus set, the hearing aid  1  is configured for use in one ear, for example the left ear. Likewise, when the selector switch assembly  9  is set in a second position mode, the connections of the outputs of the microphones are reversed, as described above, such that the first microphone  3   a  is operationally connected to the rearward second input  7   b  of the signal processing unit  7  and the second microphone  3   b  is operationally connected to the forward first input  7   a  of the signal processing unit  7 . Thus set, the hearing aid  1  is configured for use in the other ear, for example the right ear.