JPH018053Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a structure for incorporating a transmitter into a telephone handset.

(Prior Art) Conventionally, as shown in FIG. 3, the transmitter 1 of a secret telephone is placed at the position closest to the user's mouth 2 when in use, that is, at the end of the bottom surface of the handset 3. It was common to install it facing the provided sound guide hole 4.

In addition, sound guide holes are installed at one end of the handset at the top, bottom, and
There was one that was formed on three side surfaces and was configured to pick up sound from three directions (for example,
(See Publication No. 27302).

(Problem to be solved by the invention) However, in any of the above conventional techniques, the distance 1 between the user's mouth 2 and the transmitter 1 is relatively short, and the variation in this distance 1 is As the rate increases, the output level of the handset 1 also fluctuates greatly, requiring an automatic volume control device to compensate for this, and the reception performance deteriorates due to breath or saliva being blown directly onto the handset 1. The drawback is that it is easy to occur.

This invention was made to eliminate the above-mentioned drawbacks of the conventional technology, and its purpose is to reduce the rate of change in the distance between the speaker's mouth and the transmitter, and thereby to improve stability. To provide a telephone set which is capable of maintaining a high transmitting signal level and whose performance does not easily deteriorate even when used for a long period of time.

(Means for Solving the Problems) The gist of this invention to achieve the above object is to provide a handset with a receiver chamber at one end and a transmitter chamber at the other end, and a main body that supports the handset. A sound guide hole is provided which is located at the longitudinal end of the handset and opens only on one side wall surface of the transmitter chamber, and the transmitter is installed facing the sound guide hole. It consists of a telephone set.

(Function) With this structure, the distance between the sound guide hole and the speaker's mouth is relatively long. Then, in the usage state, the rate of change in distance between the two becomes low. Therefore, fluctuations in the transmitting signal level are suppressed to a low level, and a stable transmitting state is maintained.

Additionally, breath or saliva cannot be directly blown onto the handset, thereby preventing performance deterioration.

(Example) The following will be explained based on the example shown in the drawings.
As shown in FIG. 1, the handset 5 of the public-address private telephone has a receiver chamber 7 which houses a speaker/earphone, that is, a handset 6 at one end, and a transmitter chamber which houses a transmitter 8 at the other end. 9, and a grip part 11 which connects the two and has a sound-insulating sponge rubber 10 compressed and inserted into an internal cavity, and is hung and supported by a main body base part 12.

The case of this handset 5 is the upper case 13.
and a lower case 14, and a sound guide hole 16 is provided in the side wall 15 (right end in the first drawing) of the transmitter chamber 9 located at the longitudinal end of the handset 5. A transmitter 8 is incorporated in a transmitter chamber 9 facing 16.

As the transmitter 8, a highly sensitive omnidirectional electret condenser microphone is used, which is wrapped in a rubber cushion 17 and held between the protrusion 18 of the lower case 14 and the side wall 15. .

Further, a horn-shaped part 20 for loudspeaker communication is formed between the recess 19 of the main body base part 12 and the outer wall surface of the receiver chamber 7 with an appropriate distance therebetween.

With the above structure, when making a confidential call, when the handset 5 is lifted and the receiver chamber 7 is placed against the ear, the distance L between the mouth 21 and the transmitter 8 is determined.
becomes relatively long, the rate of variation in this distance L decreases, and the variation in the output level of the transmitter 8 also decreases, so there is no need for an automatic volume control circuit to compensate for level variations, and the sound Since the direction of the guide hole 16 and the direction of sound wave emission from the mouth 21 are almost perpendicular, it is possible to prevent breath or saliva from directly blowing onto the transmitter 8, and to maintain the initial state of the transmitter 8 over a long period of time. Performance is maintained.

In addition, a sound guide hole 16 is provided in the side wall 15 of the handset 5.
When a speaker 8 is provided, sound can be collected by the speaker 8 without being affected by the main body stand 12 even during loudspeaker calls.

(Effects of the invention) As described above, according to this invention, fluctuations in the input level and output level of the speaker due to variations in the distance between the speaker and the user's mouth can be kept relatively low. In addition, it is possible to prevent performance deterioration due to direct blowing of breath or saliva onto the transmitter, and it also has the effect of efficiently collecting sound during loudspeaker calls.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a telephone that implements this invention.
FIG. 2 is a sectional view of a main part of the handset in a state of use, and FIG. 3 is a sectional view of a main part of a conventional handset. 5... Handset, 8... Transmitter, 9... Transmitter chamber, 12... Main body base, 15... Side wall, 16
...Sound guide hole.

Claims (1)

[Scope of utility model registration request] It consists of a main body pedestal that supports a handset having a receiver chamber at one end and a transmitter chamber at the other end, and is located at the longitudinal end of the handset and is open only on one side wall surface of the transmitter chamber. A telephone set with a sound guide hole and a built-in transmitter facing the sound guide hole.