JPH0453680Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a chime in which a sound generation circuit and a speaker are built into a casing.

[Background technology] This type of chime that has been provided in the past is
As shown in FIG. 5, a large number of through holes 5' are bored in the front surface of the casing 1, and speakers 7 are mounted in correspondence with the through holes 5'. Therefore, the inside of the casing 1 can be seen through the through hole 5',
Furthermore, the formation of the through hole 5' on the front side of the casing 1 has the disadvantage that the appearance is impaired.

[Purpose of the invention] The present invention has been made in view of the above-mentioned points, and its purpose is to provide a chime with an excellent appearance without exposing the through holes on the front side of the casing.

[Disclosure of the invention] (Structure) The chime according to the invention is a chime in which a speaker is built into a casing, and the casing is closed at the front and the side circumferential surface on the back side is wider than the side circumferential surface on the front side. The casing is also formed in a shape with a recessed step, and at one point inside the casing there is a cylindrical holding rib with a cross-sectional shape that follows the outer periphery of the speaker and an open end that is integrally attached to the inner periphery of the casing. A closed space is formed on the back side of the speaker surrounded by the speaker, the inner circumferential surface of the casing, and the retaining rib by protruding from the speaker and arranging the speaker so that the distal end surface of the retaining rib is closed. The back side of the casing is made up of a number of through holes that transmit the sound produced by the front side of the speaker to the outside of the casing. It is made concave from the side periphery, and a through hole for transmitting the sound from the speaker to the outside is formed in that part, thereby making the through hole difficult to see from the outside.

(Example) As shown in FIG. 1, a casing 1 is formed of a body 2 having an open front surface, and a cover 3 that detachably engages with the body 2 to close the front surface of the body 2. The rear side peripheral surface of body 2 is body 2.
A stepped portion 4 is formed to be recessed from the side peripheral surface of the front portion. There is a third
As shown in FIGS. b and c, a large number of through holes 5 are bored through which the inside and outside of the casing 1 are communicated. Inside the body 2, a printed circuit board 6 on which a sound generation circuit and a push button switch 8 are mounted, and a speaker 7 are installed. Further, a battery holder 9 is formed within the body 2, so that power is supplied to the sound generation circuit. Push button switch 8 is actuator 1
0 into the base of the switch handle 11, the switch handle 11 is attached, and the front end surface of the switch handle 11 is attached to the cover 3.
It's now coming to the fore. An insertion hole 13 through which the switch handle 11 is inserted is formed on the cover 3 side, and if the switch handle 11 and the insertion hole 13 are aligned when the cover 3 is attached to or removed from the body 2, body 2 and cover 3
This allows for easy positioning. Further, a cylindrical holding rib 12 having a diameter approximately equal to the diameter of the speaker 7 is provided protruding from the inner circumferential surface of the rear wall of the body 2, and the speaker 7 is attached in a manner that closes the tip end face of the holding rib 12. . That is, a space surrounded by the speaker 7, the holding rib 12, and the inner peripheral surface of the body 2 is formed on the rear side of the speaker 7. By forming a closed space on the back side of the speaker 7 in this way, the back pressure of the cone of the speaker 7 is utilized, the sound wave energy of the speaker 7 is effectively utilized, and the sound quality is improved. In other words, by forming a closed space on the rear side of the speaker 7, it is possible to prevent interference between the sound waves sent out to the front side of the speaker and the sound waves sent out to the back side of the speaker, resulting in less distortion. It can send out clear sound. Also,
By changing the volume of the space, the frequency characteristics of the output (the frequency at which the maximum sound pressure is obtained) can be changed, making it possible to obtain the frequency characteristics desirable for the sound quality of the chime.

Since the front surface of the casing 1 formed as described above is not formed with a through hole for transmitting sound from the speaker 7 to the outside of the casing 1, the third
As shown in Figure a, a design can be applied to the front side of the casing 1. In addition, since the through hole 5 is formed corresponding to the stepped portion 4 that is recessed from the side circumference of the front part of the casing 1, the through hole 5 will be hidden in the shadow when the casing 1 is attached to a wall surface, etc. This makes it less noticeable when worn, resulting in an even better appearance.

Furthermore, as shown in FIG. 4a, the back surface of the body 2 is generally used in contact with the wall surface 14, but when attached to the door 15, as shown in FIG. 4b.
As shown in FIG. 2, it is also possible to select a mode of use in which the cover 3 is joined to the back side of the body 2 and the opening surface of the body 2 is directly attached to the door 15.
In the latter case, the back side of the body 2 becomes the front side of the door 15, but since the back side of the body 2 is covered by the cover 3, the appearance is not spoiled.
As described above, it is possible to select two types of usage for one type of product, which leads to cost reduction.

[Effects of the invention] As mentioned above, the present invention is a chain in which a speaker is built into the casing, and the casing is closed at the front and the side circumferential surface on the back side is recessed more than the side circumferential surface on the front side. A cylindrical holding rib with a cross-sectional shape along the outer periphery of the speaker and an open end is integrally protruded from the inner periphery of the casing. By arranging the speaker so that the tip surface of the retaining rib is closed, a closed space surrounded by the speaker, the inner peripheral surface of the casing, and the retaining rib is formed on the back side of the speaker, and the casing is closed. The side surface on the back side is made up of a number of through holes that transmit the sound produced on the front side of the speaker to the outside of the casing, and the side surface on the back side of the casing is It is formed in a shape that is more concave than the side circumference, and a through hole is formed in the side circumference on the back side to send the sound from the speaker to the outside, so the through hole is not exposed on the front side and is not recessed. Since the through holes are formed in the outer portion, the through holes are hidden in the shadows and are difficult to see, resulting in an advantage that an excellent appearance can be achieved. In addition, since the space on the back side of the speaker is surrounded and closed by the holding rib, the inner circumferential surface of the casing, and the speaker, the back pressure of the speaker is effectively used, and the sound pressure level of the speaker is improved. This has the advantage of improving sound quality. In other words, since a closed space is formed on the rear side of the speaker, it is possible to prevent interference between the sound waves sent to the front side of the speaker and the sound waves sent to the back side of the speaker, producing clear sound with little distortion. Furthermore, by changing the volume of the space, the frequency characteristics of the output (the frequency at which the maximum sound pressure is obtained) can be changed, making it possible to obtain the desired frequency characteristics for the sound quality of the chime. This effect is produced.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing one embodiment of the present invention, Fig. 2 is a partially cutaway rear view of the same, and Fig. 3 a, b, c.
4 are a front view, a side view, and a back view of the same as above, FIGS. 4a and 4b are sectional views showing the usage pattern of the above, and FIG. 5 is a sectional view of a conventional example. 1 is a casing, 4 is a step, 5 is a through hole, 7 is a speaker, and 12 is a holding rib.

Claims (1)

[Scope of utility model registration request] The casing has a built-in speaker inside the casing, and the casing is closed at the front and has a stepped part on the back side that is more recessed than the front side. A cylindrical holding rib with a cross-sectional shape that follows the outer periphery of the speaker and whose tip end is open is integrally provided at one place and protrudes from the inner circumferential surface of the casing, so that the tip end of the holding rib is closed. By arranging the speaker on the rear side of the speaker, a closed space surrounded by the speaker, the inner circumferential surface of the casing, and the retaining rib is formed on the back side of the speaker, and a closed space is formed on the side circumferential surface of the back side of the casing on the front side of the speaker. A chime with many holes that transmit the sound to the outside of the casing.