JPS58161557A - Loudspeaking telephone set - Google Patents

Abstract

PURPOSE:To reduce easily the sound coupling quantity between a speaker and a microphone and to improve the talking performance, by attaching either one of the speaker and microphone which are used to a band-free call to a hand set and the other to a base set respectively. CONSTITUTION:A speaker 1 and a microphone 2 are packed into a base set 5 and a handser 6 in separate housings respectively. Thus the sound coupling quantity due to the internal sounds is greatly reduced. Then the handset 6 is put on a handset receiver 7 which is attached to the base set 5. Under such conditions, a hand-free call is carried out. In such a way, the vibrations produced through the speaker 1 are greatly attenuated while they are transmitted to the microphone 2 of the handset 6 from the set 5 through the receiver 7. This can reduce the sound coupling quantity caused by vibrations.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a public address telephone consisting of a handset and a pace set, by reducing the amount of sound switching coupling between the speaker and the microphone, and by using both a converter for handset calls and a converter for hands-free calls. This relates to an economical speaker/microphone mounting structure.

Conventionally, in a public address telephone set consisting of a handset and a pace set, both the speaker and the microphone used for handset-to-phone calls were mounted on the pace set. Therefore, the acoustic coupling between the loudspeaker and the microphone is divided into three types, as detailed below, due to the difference in their paths.
There are too many of them.

The acoustic coupling path in an implementation example of a conventional public address telephone is shown in FIG. 1. In the figure, 1 is a speaker, 2 is a microphone, 3 is a speaker box, 4 is a microphone box, and 5 is a public address telephone. This is a pace set.

In the first path ■, the sound from the speaker 1 propagates through the external space of the pace set S and reaches the microphone 2 through acoustic coupling (acoustic coupling due to external sound), and the second path 11! is an acoustic coupling (acoustic coupling due to internal sound) caused by the sound emitted from the speaker 1 to the rear surface passing through the speaker box 3 and entering the microphone 2, or partially going outside through the pace set 4 and entering the microphone 2 again. ), and the third path (2) is acoustic coupling (acoustic coupling due to vibration) in which the vibrations of the speaker 1 are transmitted through the base cell (S) and enter the microphone 2 as vibrations.

Acoustic coupling is the main cause of howling in loudspeaker telephones, and reducing the amount of this coupling is important in improving the communication performance of loudspeaker telephones.

Conventionally, the first path ■, that is, the "amount of acoustic coupling due to external sound" is mainly related to the positional relationship between the speaker and the microphone and the directivity of the speaker 1 and the microphone 20. Efforts have been made to reduce this by increasing the distance between the two, or by using speakers and microphones with sharp directivity.

However, the second path ■, that is, [because both internal microphones 2 and 2 are installed in the pace set S,
It is difficult to reduce the vibration, so conventionally, when attaching the rear part of the speaker 1 and microphone 2 to the speaker box 3, microphone box 4, and pace set 5, an anti-vibration structure using anti-vibration rubber etc. was used to block vibrations. Attempts have been made to reduce the amount of acoustic coupling by methods.

However, this method requires a speaker box 3, a microphone box 4, and anti-vibration parts to isolate internal sounds and vibrations, and has the disadvantage that increased costs are unavoidable when assembling and maintaining the parts. was there. Furthermore, since these mounted components occupy a large volume, it is difficult to miniaturize the telephone.

In view of the above points, the present invention has been devised to solve such problems and eliminate such drawbacks.The purpose of the present invention is to easily reduce the amount of acoustic coupling between the speaker and the microphone, and thereby improve communication. An object of the present invention is to provide a loudspeaker telephone capable of improving performance, making the telephone more economical, and making the telephone smaller.

In order to achieve such an object, the present invention is such that one of a speaker and a microphone used for hands-free calling is mounted on a handset, and the other is mounted on a pace set. Examples of the present invention will be described in detail.

FIG. 82 is a perspective view showing an embodiment of a loudspeaker telephone according to the present invention. In FIG. 2, the same reference numerals as in FIG. 1 indicate corresponding parts, 6 is a handset, T is a handset receiver, 8 is a slit for a speaker, and 9 is a slit for a microphone.

Figures 3(a) and 9(b) illustrate the embodiment of Figure 2.
iii is a cross-sectional view viewed from J force 1. This is shown in Figure 3 (b
), the speaker 1 is installed in the pace set 5, and the microphone 2 is installed in the handset 6, as shown in FIG. Attached handset receiver 7 (
The device is configured so that hands-free calls can be made while the device is placed on a vehicle (see FIG. 2).

Next, the operation of the embodiment shown in FIG. 2 will be explained.

First, the acoustic coupling by the external sound indicated by the first path {circle around (2)} shown in FIG. 1 will be explained.

4(a) is a plan view of FIG. 2 viewed from above, and FIG. 4(b) is a plan view of the implementation example of the conventional loudspeaker telephone shown in FIG. 1 viewed from above. In the figure, it is assumed that T is the end set receiver, 1G is the center position of speaker 1, 11 is the center position of microphone 2, and the external dimensions of the loudspeaker telephones in (a) and >) are the same. . Assuming that the distance from the center position 10 of the speaker 1 to the center position 11 of the microphone 2 is 1 m in Figure 4-) and lvt in Figure 4-), each of these distances is 11AIHIIB.
are respectively expressed by the following equations.

JR=4(b+e)+1 1B=4m”+b” ζ Here, a, b, @) is 0.

Therefore, In>In, and by implementing the present invention, the distance between the speaker 1 and the microphone 2 can be made longer than in the implementation example of the conventional loudspeaker telephone. Therefore, it is possible to reduce the amount of acoustic coupling caused by the external sound indicated by the first path (3) shown in FIG.

FIG. 5(1) shows a perspective view of the handset part of FIG. 2, and FIG. 5(b) shows a perspective view of the pace set part of FIG. In the embodiment of the present invention, as shown in FIG. 5(a), the size of the nose set 6 is small, and when the microphone 2 is mounted, the microphone slit 9 is arranged in the upper, lower, left, right, and front directions. It can be easily provided in five directions. On the other hand, in the implementation example of the conventional loudspeaker telephone, as shown in FIG. No. 3
Only the direction can be set. In addition, in Figure 5), 8
is a slit for a speaker. In general, if a directional microphone is mounted to approximate a free sound field, ideal directional characteristics can be obtained.

This FIG. 5(1) is freer than FIG. 5(a), and can reduce the amount of acoustic coupling due to the multiplication part noise, which is indicated by the first path (3) shown in FIG.

Next, a description will be given of the tone-to-reference coupling due to internal noise shown in the second path 0 shown in FIG.

In the implementation example of the present invention, as shown in FIG. 3, the speaker 1 is separated into a pace set S, and the microphone 2 is separated into a handset @, which are mounted in nine housings. This is because the pace set 5 corresponds to the speaker box 3 in FIG. 1, the handset 6 corresponds to the microphone box 4 in FIG. 1, and the internal sound indicated by the second path ■ in FIG. It has the same or greater effect on reducing the amount of acoustic coupling due to First, the speaker box 3 and the microphone box 4 are not required, and as a result, the loudspeaker telephone can be made smaller and more economical.

If the speaker box 3 and the microphone box 4 are used together with the present invention, the amount of acoustic coupling will be further reduced and the communication performance will be improved.

Next, the stone acoustic coupling by vibration shown in the third path (3) shown in FIG. 4 will be explained.

In the implementation example of the present invention, as shown in FIG. 3, the speaker 1 is mounted on the pace set 5, and the microphone 2 is mounted on the handset 6 in separate casings.
The pace set 5 is configured so that a hands-free call can be made by simply placing it on the handset holder T attached to the pace set 5. Therefore, vibrations generated from the speaker 1 are significantly attenuated when transmitted from the pace set 5 through the handset receiver T to the microphone 2 of the handset 6, and the amount of acoustic coupling due to vibrations can be reduced. In this case, the vibration isolating parts required in the mounting example shown in FIG. 1 are not required, and as a result, the device can be made smaller and more economical.

Note that if a vibration-proofing component is used in combination with the present invention, the amount of acoustic coupling will be further reduced and the communication performance will be improved.

Although the present invention has been described above using an example in which the speaker 1 is mounted on the pace set 5 and the microphone 2 is mounted on the handset 6, the present invention is not limited to this, and other embodiments of the present invention may be implemented. FIG. 6 shows a perspective view of an example, and FIG. 7 (1
), it is clear that the same effect as described above can be obtained even if the speaker 1 is placed in the handset 6 and the microphone 2 is placed in the pace set 5.

8 and 9 are perspective views showing still other embodiments of the present invention, and FIG. 8 is an application example using FIG. 2, which is a perspective view showing one embodiment of the present invention), In FIGS. 8 and 9, the same reference numerals as in FIGS. 2 and 6 indicate corresponding parts, 12 is a mouthpiece, and 13 is a mouthpiece. In the embodiment shown in FIG. 8, the speaker 1 is mounted on the base speaker) S, and the microphone 2 is mounted on the mouthpiece 13 of the handset 6, so that the amount of acoustic coupling can be reduced. In addition, the microphone 2t handset can also be used as a transmitter during calls, making it possible to make the telephone more compact and economical.

Further, FIG. 9 is an application example using FIG. 6 which is a perspective view showing another embodiment of the present invention, in which the speaker 1 is mounted on the earpiece 12 of the handset 6, and the microphone 2 is mounted on the earpiece 12 of the handset 6. Since the pace set SK is included, in addition to being able to reduce acoustic coupling, the speaker 1 can also be used as a handset during handset calls, making it possible to make the telephone more compact and economical.

As described above, the present invention is a telephone set consisting of a handset and a base set, in which a speaker and a microphone used for hands-free calls are installed separately in the handset and pace set. Therefore, by using the implementation of the present invention, it is possible to easily reduce the amount of acoustic coupling between the speaker and the microphone, improve the communication performance, and also improve the speaker box, microphone box, and housing vibration for shielding the internal sound of the housing. This eliminates the need for anti-vibration components, which is advantageous in making telephones more economical and smaller. In addition, by using the speaker or microphone mounted on the handset side as a handset receiver or transmitter, it is possible to provide a much smaller and cheaper electric spinning machine. and,
The present invention has similar effects in reducing acoustic coupling and making smaller and more economical devices such as intercoms and general public address systems in addition to telephones.

As described above, the present invention has many advantages over conventional loudspeaker telephones, and is unique as a loudspeaker telephone consisting of a handset and a pace set.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the path of acoustic coupling in an implementation example of a conventional loudspeaker telephone, Fig. 2 is a perspective view showing an embodiment of the loudspeaker telephone according to the present invention, and Fig. 3 is a side view of Fig. 2. Cross-sectional view, Figure 4-) is a plan view of Figure 2 viewed from above, Figure 4 (K) is a flat plan view of Figure 1 viewed from above, Figure 5 (&)
is a perspective view of the handset section in Figure 2, and Figure S is a perspective view of the handset section in Figure 1.
6 is a perspective view showing another embodiment of the present invention, FIG. 7 is a sectional view of FIG. 6 seen from the side, and FIGS. 8 and 9 are FIG. 7 is a perspective view showing still another embodiment. 1...Speaker, 2...Microphone, S-...
... public address telephone pace set, 6 ... handset, 12 ... earpiece, 13 ... mouthpiece. Patent applicant Masaki Yamakawa, agent for Nippon Telegraph and Telephone Public Corporation Figure 1 Figure 4 Figure 2 Figure 3 Figure 4 Figure 5

Claims (2)

[Claims] (1) In a telephone set consisting of a handset and a pace set, one of a speaker and a microphone used for hands-free calls is mounted on the handset, and the other is mounted on the pace set. telephone. (2) In a telephone set consisting of a handset and a pace set, one of a speaker and a microphone used for hands-free calls is installed in the handset, the other is installed in the pace set, and a speaker and a microphone used for hands-free calls are installed, and the other is installed in the pace set. 9. A loudspeaker telephone set characterized in that the speaker and the microphone for hands-free calls are used together, or the handset for handset calls and the speaker for hands-free calls are used together.