JP2003009271A - Receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a receiver having enhanced radiation sensitivity and jamming preventing characteristic. SOLUTION: An outer package 1 incorporates a speaker 3 and a printed circuit board 2 on which various circuits including a reception circuit in compliance with the Bluetooth standard. A pad 4 closely adheres a wireless headphone to a human body (ear) 5 to shut off an external sound and to prevent a sound outputted from the speaker 3 from being externally leaked. A conductor 6 and an inductor 7 are interposed between the human body (ear) 5 and ground of the printed circuit board 2. Thus, resonance is taken between the human body (ear) 5 and the ground of the printed circuit board 2 and a disturbing frequency is set at an anti-resonance point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headphone device or the like mounted on a user's ear, and relates to a receiving device for receiving data wirelessly transmitted from a reproducing device.

[0002]

2. Description of the Related Art In recent years, as a wireless communication technology for transmitting and receiving data between various electronic devices by short-range wireless communication, there are features such as easy connection, simple circuit configuration, and low power consumption. Bluetooth (registered trademark) is drawing attention.

As one of Bluetooth devices, there is known a system in which audio data decoded by a reproducing device is wirelessly transmitted, received by wireless headphones worn by a user, and output as a musical tone.

[0004]

However, in the conventional wireless headphones, since the capacitive coupling between the printed circuit board on which the circuit is mounted and the human body (ear part) is small, the ground plane becomes fragile as a circuit, and There was a problem that it was not possible to bring out the optimum radiation sensitivity.

Therefore, an object of the present invention is to provide a receiving apparatus which can improve radiation sensitivity and interference characteristics.

[0006]

To achieve the above object, a receiving device according to the present invention is used in contact with an ear of a human body to receive musical tone information transmitted wirelessly. A conductive member disposed between a circuit board on which an electronic circuit is mounted and the ear portion, and an inductive member having an inductance by electrically coupling the circuit board and the conductive member. It is characterized by including.

As a preferred mode, for example, as in claim 2, in the receiving device in claim 1, the inductive member electrically connects the ground of the circuit board and the conductive member. You may

As a preferred embodiment, for example, as described in claim 3, in the receiving device according to claim 1, the capacitance formed by the ear portion and the conductive member, the conductive member and the circuit board. A resonance circuit may be configured by the capacitance formed in (4) and the inductance of the inductive member.

As a preferred aspect, for example, as described in claim 4, in the receiver according to claim 3, the anti-resonance point of the resonant circuit may be set to the frequency band of the interfering signal.

According to the present invention, a conductive member is disposed between the circuit board on which an electronic circuit is mounted and the ear portion, and the circuit board and the conductive member are electrically connected by an inductive member having an inductance. Join. Therefore, the radiation sensitivity can be improved, and the interference characteristic can be improved.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a structure of a wireless headphone according to an embodiment of the present invention. Inside the exterior 1, a printed wiring board 2 and a speaker 3 on which various circuits including a receiving circuit conforming to the Bluetooth standard are mounted.
And are built in. The pad 4 is for keeping the wireless headphones in close contact with the human body (ear part) 5 to block sounds from the outside and to prevent sounds output from the speaker 3 from leaking to the outside. Between the human body (ear part) 5 and the ground of the printed wiring board 2, a conductive conductor 6 such as a metal and an inductance 7 are interposed.

In the present embodiment, the conductor 6 and the inductance 7 are inserted between the human body 5 and the ground of the printed wiring board 2 to resonate between the human body 5 and the ground of the printed wiring board 2. On the other hand, the interference frequency is selected at the anti-resonance point.

FIG. 2 is a circuit diagram showing an equivalent circuit of the above wireless headphones. The stray capacitance C ₁ is equal to the conductor 6
And the capacitance between the printed wiring board 2 and the printed wiring board 2. The stray capacitance C ₂ is the capacitance interposed between the conductor 6 and the human body (ear) 5. Here, FIG. 3 is a conceptual diagram showing frequency characteristics of the wireless headphones according to the present embodiment. In the wireless headphones according to the present embodiment, as shown in FIG. 3, the equivalent circuit shown in FIG.
A resonance point (f ₁ ) and an anti-resonance point (f ₂ ) can be obtained.

In the above equivalent circuit, the printed wiring board 2
The impedance Z (see the upper part of FIG. 3) between the ground and the human body (ear) 5 is represented by the following mathematical formula 1.

[0015]

[Equation 1]

Therefore, the resonance point (f ₁ ) when the impedance Z = 0 and the anti-resonance point (f ₂ ) when the impedance Z = infinity are expressed by the following mathematical expression 2 (the lower part of FIG. 3 is shown. reference).

[0017]

[Equation 2]

For example, the sensitivity at 2.4 GHz is improved.
The capacity C₁, C_Two, Resonance point f ₁(2.4 GHz)
If the value of the resonance inductance L is determined according to
Yes. The capacity C₁, C_TwoThe value of is the size of the conductor 6,
The distance between the printed wiring board 2 and the conductor 6, the conductor 6 and the ear 5
These parameters are appropriate because they change according to the distance of
By selecting, it is possible to set the optimum value. Also,
Anti-resonance point (f_Two) To the frequency band of the interfering signal.

In the above-described embodiment, the conductor 6 and the inductance 7 are provided between the human body 5 and the ground of the printed wiring board 2.
By adding resonance with the human body 5 and the ground of the printed wiring board 2 to obtain a sufficient ground effect at the reception frequency, and by selecting the anti-resonance point as the interference frequency in the constant design, the radiation sensitivity can be improved. And the interference characteristics are improved.

[0020]

According to the invention of claim 1, a conductive member is disposed between the circuit board on which an electronic circuit is mounted and the ear portion, and the circuit board and the conductive member are connected to each other with an inductance. Since they are electrically coupled by the inductive member that they have, there is an advantage that the radiation sensitivity can be improved and the interference characteristics can be improved.

According to the second aspect of the invention, since the inductive member electrically connects the ground of the circuit board and the conductive member, the radiation sensitivity can be improved. The advantage is that the interference characteristics can be improved.

According to the third aspect of the invention, the capacitance formed by the ear portion and the conductive member, the capacitance formed by the conductive member and the circuit board, and the inductive member Since the resonance circuit is configured by the inductance, there is an advantage that the radiation sensitivity can be improved and the interference characteristic can be improved.

According to the fourth aspect of the invention, since the anti-resonance point of the resonance circuit is set in the frequency band of the interference signal, the radiation sensitivity can be improved and the interference characteristic can be improved. The advantage is that it can.

[Brief description of drawings]

FIG. 1 is a sectional view showing a structure of a wireless headphone according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing an equivalent circuit of the wireless headphones according to the embodiment of the present invention.

FIG. 3 is a conceptual diagram showing frequency characteristics of the wireless headphones according to the present embodiment.

[Explanation of symbols]

1 ... Exterior, 2 ... Printed wiring board (circuit board), 3 ...
... Speaker, 4 ... Pad, 5 ... Human body (ear), 6 ...
… Conductor (conductive member), 7… Inductance (inductive member)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tadashi Fukami             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Toru Hayashibara             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Masashi Kimoto             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F-term (reference) 5D005 BA02                 5D020 AC00                 5K016 AA07 BA00 CA01 CC04                 5K052 AA01 BB02

Claims (4)

[Claims] 1. A receiving device, which is used in contact with an ear of a human body and receives musical tone information transmitted by radio, comprising a circuit board on which an electronic circuit is mounted and the ear. A receiving device comprising: a conductive member provided; and an inductive member that electrically couples the circuit board and the conductive member and has an inductance. 2. The receiving device according to claim 1, wherein the inductive member electrically couples the ground of the circuit board and the conductive member. 3. Resonance due to a first capacitance formed by the ear portion and the conductive member, a second capacitance formed by the conductive member and the circuit board, and an inductance of the inductive member. The receiving device according to claim 1, which constitutes a circuit. 4. The receiver according to claim 3, wherein an anti-resonance point of the resonance circuit is set in a frequency band of an interference signal.