CN85107348B

CN85107348B - Audi-frequency earpiece without power and wires

Info

Publication number: CN85107348B
Application number: CN85107348A
Authority: CN
Inventors: 赖晓威
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-09-30
Filing date: 1985-09-30
Publication date: 1988-04-27
Also published as: CN85107348A

Abstract

The present invention provides an audio wireless signal transmitting and receiving device without a power supply or an amplifier. The transmitting and receiving device overcomes the disadvantages that a general wireless earphone must be provided with a low frequency power amplifier, a circuit is complicated owing to an induced weak audio current of the power supply by an amplifying induction coil, the cost is high, etc. The area and the coil number of the induction coil are rationally increased, meanwhile, a volume of a permanent magnet as an electroacoustic transducer is increased, and the output power of a transmitting apparatus and the coil number the transmission coil are properly increased. Thus, the received signal energy is enhanced. The transmitting and receiving device has the advantages of simple structure and low cost, and is suitable for popularization and application on various occasions requiring avoidance of noise interference.

Description

Audi-frequency earpiece without power and wires

The present invention relates to signal transmission system, relating more specifically to the audio wireless non-transformer does not have the amplifier signal receiving system.

General audio wireless signal receiver (being commonly called as wireless headset) all is equipped with a low-frequency power amplifier, and the weak audio signal of telecommunication that receives is become the stronger signal of telecommunication, drives the load earphone with enough energy, makes the listener obtain sound clearly.Low frequency amplifier need have power supply, for example battery, and to its energy regenerative, and battery in use needs often to change, and is fragile so such wireless earphone circuit is complicated, cost is higher, uses maintenance all inconvenient.

Task of the present invention is to provide a kind of Audio frequency radio earphone that does not need amplifier and battery, it can directly become people's ear to the audio signal that receives can clearly debate the acoustical signal of listening, thereby overcomes the disadvantage of traditional wireless headset, simplified structure, reduce cost easy to use and management.

Task of the present invention is that the principle of using electromagnetic induction realizes.According to electromagnetic induction principle, in certain space, constitute a loop with lead, with the audio signal feed-in, then just form an audio frequency alternating magnetic field in the space that this transmitting coil centered on, become the closing coil of certain angle of cut to be subjected to this influence of magnetic field and in induction coil, to produce induced current in every this magnetic field with the magnetic line of force, according to maxwell's law of electromagnetic induction, size at two coils, shape, the number of turns, when relative position and magnetic permeability are constant, the induced electromotive force of induction coil is to be directly proportional with the number of turns of two coils, be directly proportional with the area of induction coil, also be directly proportional with the electric current of feed-in in the transmitting coil perpendicular to transmitting coil magnetic line of force direction.Though general wireless headset has also utilized the principle of electromagnetic induction, the effective area of its induction coil is very little, pact≤1cm ²So its signal that receives is just very faint, must amplify through low frequency amplifier, could promote the earphone interior diaphragm and sound.And the present invention is according to above analysis, by the area and the number of turns that reasonably increases induction coil, next adopts the bigger permanent magnet of volume to make the electroacoustic transducer of earphone, the number of turns that is aided with the power output of the amplifier in the suitable enhancing audio signal emitter and transmitting coil improves the energy of the signal that receives, so just, desirable noise reduction audio amplifier and power supply thereof, and reach same audibility.Apparatus structure of the present invention is simple, cost is very low, use and management is convenient, be applicable to the occasion that to avoid sound equipment to disturb, thereby may be subjected to hall that reflected sound disturbs etc. as foreign language teaching, sound reading room, several contiguous classrooms and meeting-place, the design of no sound equipment fidelity.

The present invention is described in further detail below in conjunction with accompanying drawing.

Fig. 1 is a kind of contour structures schematic diagram of Audi-frequency earpiece without power and wires of the present invention.

Fig. 2 is a kind of Audi-frequency earpiece without power and wires that has iron core.

Fig. 3 a is a diaphragm type electroacoustic transducer structural representation.

Fig. 3 b is a moving-coil type electroacoustic transducer architecture schematic diagram.

Fig. 4 a is the connected mode schematic diagram that links to each other with induction coil again after two electroacoustic transducer series connection.

Fig. 4 b is the connected mode schematic diagram that links to each other with induction coil again after two electroacoustic transducer parallel connections.

Fig. 5 a to Fig. 5 f is the contour structures schematic diagram of various forms of Audi-frequency earpiece without power and wires, wherein:

Fig. 5 a is the broadband type Audi-frequency earpiece without power and wires.

Fig. 5 b is the helmet-type Audi-frequency earpiece without power and wires.

Fig. 5 c is the parachute-type Audi-frequency earpiece without power and wires.

Fig. 5 d is thin diamond type Audi-frequency earpiece without power and wires.

Fig. 5 e is a circumference formula Audi-frequency earpiece without power and wires.

Fig. 5 f is the elliptic Audi-frequency earpiece without power and wires.

Fig. 5 a ' is respectively the end view of Fig. 5 a to Fig. 5 f to Fig. 5 f '.

Fig. 6 is the work block diagram that Audi-frequency earpiece without power and wires of the present invention and audio signal emitter are used.

As shown in Figure 1, non-transformer wireless headset of the present invention mainly by induction coil (1), two electroacoustic transducers (2) that are connected with induction coil (1) end, support the head bow (3) of induction coil (1), fixedly electroacoustic transducer (2) and with this electroacoustic transducer (2) with bend the transducer mount (4) that (3) be connected and form.The shape of head bow (3) is made and is suitable for being enclosed within on user's head, and it uses injection molded, and the central part in its inside attaches induction coil (1), and is topped with foamed plastics, and innermost layer is again with plastic film or artificial leather parcel.Induction coil (1) line directly is 0.2～0.22 millimeter, about 60～80 ohm of D.C. resistance, and it is placed on the transmitting coil plane of the audio emitting device that is used with this device has on the orientation of maximal projection area, so that make the signal that receives big as far as possible.The effective area of induction coil is the bigger the better in theory, but considers the actual convenience of using and attractive in appearance, desirablely equals or approaches the projected area of user's head on the transmitting coil plane, is about 100cm ²To 200cm ², bigger more than 100 times than the effective area of existing wireless headset induction coil.The number of turns of induction coil (1) also is The more the better in theory, but consider its impedance must with electroacoustic transducer (2) coupling, and the unlikely increase of weight is too many, thus a desirable compromise, about 800 circles.The arrangement mode of induction coil is generally taked coil bundle formula, also can take spider web board-like, if take the arrangement of coil bundle formula, can in the area of induction coil (1) institute contour, settle iron core (5) to improve the effect of received signal, as shown in Figure 2, but the disadvantageously corresponding increase of weight of device.

The electroacoustic transducer of this device (2) is selected 60～120 ohm chip permanent magnet transducer for use, its structure is shown in Fig. 3 a, the about 40mm of diaphragm (7) diameter wherein, two groups of coils (8) winding is 0.132mm * 900 circles, permanent magnet (9) is got No. 3 magnet steel of U-shaped, and its volume is 300～1000mm ³, bigger approximately 1～3 times than the electroacoustic transducer volume of general wireless headset, it also can make moving-coil structure, shown in Fig. 3 b.The sheath that the sounding mouth of electroacoustic transducer (2) is done with foaming plastic body (6) is wrapped up, to increase comfort.Two electroacoustic transducers (2) can be decided according to their impedance matching with the connected mode of induction coil (1), are beneficial to make energy to consume as far as possible and are as the criterion on transducer (2) rather than induction coil (1).Fig. 4 a and Fig. 4 b represent the connected mode and the later connected mode that links to each other with induction coil (1) again of parallel connection that link to each other with induction coil (1) again after two electroacoustic transducers (2) series connection respectively, each pays earphone two electroacoustic transducers (2), they respectively have two lead-out wires, the mode of being connected in series shown in Fig. 4 a is that each lead-out wire of two electroacoustic transducers is continuous, and each links to each other another lead-out wire with an end of induction coil.The mode of being connected in parallel shown in Fig. 4 b is that each two lead-out wire of two electroacoustic transducers (2) are continuous in twos respectively, two lines is linked to each other with induction coil (1) again.

The transducer mount of this device (4) adopts thicker wire, makes U type structure as the steel wire of φ 3mm, handles through chromium plating, also can do support with other metal or duroplasts.

Audi-frequency earpiece without power and wires of the present invention, except adopting surface structure shown in Figure 1, can also be by induction coil (1) be suitable for being enclosed within conversion on user's head arbitrarily from the shape of it attached head bow (3), make the earphone profile that shape determined by head bow (3) have various multi-form shown in Fig. 5 a to 5f, as broadband type, helmet-type, parachute-type, thin diamond type, circumference formula, elliptic etc., Fig. 5 a ' is respectively the end view of Fig. 5 a to 5f to 5f '.Dotted line among these figure is all represented the position of induction coil (1).

Audi-frequency earpiece without power and wires of the present invention must be used with the audio signal emitter, and Fig. 6 is its working envelope figure.Audio signal feed-in transmitting coil (12) after audio frequency amplifier (11) amplifies that low frequency signal source (10) sends as microphone, phonograph or recorder etc., transmitting coil (12) is around the required space that comprises induction coil that is transferred to of signal, classroom for example, along its wall parallel to the groundly around several weeks, audio frequency amplifier (11) should adopt that power is big, volume is little, in light weight, BTL amplifier that power output is stable, also can adopt OTL amplifier or OCL amplifier, its power output is decided by sending area.For example, when using Audi-frequency earpiece without power and wires of the present invention, for a 100m ²Lyceum, should use the audio frequency amplifier of 150W, less than 50m ²The room can adopt the audio frequency amplifier of 50～75W, and 200m ²The hall then should use the audio frequency amplifier of 300W, like this, faradic signal to noise ratio is better, thereby reception might as well.The number of turns of transmitting coil (12) its length increase in other words can improve the signal energy that receiver receives, but it must be complementary with the output impedance of audio frequency amplifier (11), otherwise the phenomenon that the possibility produce power can not carried or the emitter overload burns out.Transmitting coil (12) is generally got 5～6 circles, and it should be made with single copper core plastic covered wire.

Claims

1, a kind of audio wireless non-transformer does not have the amplifier signal receiving system, it by induction coil (1), two electroacoustic transducers (2) that are connected with induction coil (1) end, support the head bow (3) and the fixing electroacoustic transducer (2) and this electroacoustic transducer (2) and head are bent the transducer mount (4) that links to each other form on user's head of being enclosed within of induction coil (1), it is characterized in that induction coil (1) is attached at the central part of head bow, can place user's head, and the effective area of induction coil (1) is 100cm ²To 200cm ²

2, by the described device of claim 1, permanent magnet (9) volume that it is characterized in that forming electroacoustic transducer (2) is 300mm ³To 1000mm ³

3,, it is characterized in that described two electroacoustic transducers (2) are to link to each other with induction coil (1) after adopting series system or parallel way to connect again by the described device of claim 1.

4, by claim 1 or 2 or 3 described devices, it is characterized in that electroacoustic transducer (2) is a diaphragm type permanent magnet electroacoustic transducer, or moving-coil type permanent magnet electroacoustic transducer.

5, by claim 1 or 2 or 3 described devices, the arrangement mode that it is characterized in that induction coil (1) is a coil bundle formula.

6,, it is characterized in that the interior iron core of settling of area that induction coil (1) is enclosed by the described device of claim 5.

7, by claim 1 or 2 or 3 described devices, the arrangement mode that it is characterized in that induction coil (1) is that spider web is board-like.

8,, it is characterized in that the form of the head bow (3) that described induction coil (1) is attached can adopt broadband type, helmet-type, parachute-type, thin diamond type, circumference formula or the elliptic that is suitable for being enclosed within on user's head by claim 1 or 2 or 3 described devices.

9,, it is characterized in that the head bow is with injection mo(u)lding or use the metal frame structure, the central part arrangement induction coil (1) in its inside by the described device of claim 8.Topped with foamed plastics, innermost layer is wrapped up in plastic film or artificial leather.

10, by the described device of claim 1, its spy is that transducer mount (4) makes with U type thicker wire or other metal or duroplasts.

11,, it is characterized in that the sheath that the sounding mouth of electroacoustic transducer (2) is done with foaming plastic body is wrapped up by claim 1 or 2 or 3 described devices.