JPH0117906Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an acoustic transducer used as a sound signal in, for example, various watches, cameras, microwave ovens, portable video cameras, tape recorders, pagers, and the like. The present invention is an acoustic transducer of this type, by adding end electrodes to the substrate on which the acoustic transducer is mounted and making it into a chip.
This allows for easier assembly, automatic mounting during mounting work, and miniaturization and thinning.

PRIOR ART Although piezoelectric type acoustic transducers and the like are known as this type of acoustic transducer, recently, electromagnetic type acoustic transducers that have a resonance point in a low frequency region of around 2 KHz have been attracting attention. This electromagnetic acoustic transducer obtains vibration by exciting a diaphragm through magnetic interaction between a direct current magnetic field and an alternating current magnetic field.

FIG. 5 is a front sectional view of a conventional example of an electromagnetic acoustic transducer.
By arranging a cylindrical permanent magnet 5 such as a ferrite magnet or a plastic molded magnet so as to surround an electromagnet made of A structure in which an acoustic transducer is configured, and the acoustic transducer is fitted into the inner diameter part 102 of a cylindrical case 1 made of a non-magnetic metal material, synthetic resin, etc. through a bottom opening 101 by means such as press fitting. It is becoming. A terminal board 7 is attached to the bottom opening of the case 1 together with the yoke 4, and has pin-shaped terminals 8 and 9 implanted therein for electrically connecting the coil terminals of the coil 2. This terminal board 7 is made of insulating resin.

Furthermore, the upper surface 1 of the case 1 in front of the diaphragm 6
A sound emitting hole 10 is opened in the center of the case 1, and the vibration sound of the acoustic converter is emitted to the outside of the case 1 through the sound emitting hole 10.

Problems to be Solved by the Invention As mentioned above, the conventional structure was such that pin-shaped terminals 8 and 9 were embedded in the board 7 as power supply terminals for the acoustic converter, so it was not possible to use a watch, a camera, or a microwave oven. When implementing it on various devices such as
The pin-shaped terminals 8 and 9 must be aligned with the pin insertion holes of the circuit board provided on the equipment side. For this reason, it has been extremely difficult to automate the implementation on the device side in the conventional method.

In addition, since the pin-shaped terminals 8 and 9 are embedded in the flat board 7, it is difficult to secure the terminals 8 and 9 with sufficient strength, and the terminals may be damaged by soldering heat. When the mounting base was heated, the terminals 8 and 9 were likely to become unstable and fall off.

If the thickness of the terminal mounting part of the board 7 is increased,
The mounting strength of the terminals 8 and 9 can be increased, but in this case, the thickness of the board 7 increases.
The overall height has increased, making it impossible to meet the demands of the times for miniaturization.

The object of the present invention is to solve the above-mentioned conventional problems and provide an acoustic transducer that is easy to assemble, can be automatically mounted during mounting, and is small and thin.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the present invention provides a method in which at least a part of the terminal electrodes is formed on one surface of a substrate having a planar terminal electrode formed on the end thereof. The device is characterized in that an acoustic transducer is mounted so as to be exposed, and a lead wire of the acoustic converter is conductively connected to the terminal electrode.

Embodiment FIG. 1 is a front sectional view of an acoustic transducer according to the present invention, FIG. 2 is a side sectional view thereof, and FIG. 3 is an exploded perspective view thereof. In the figure, the same reference numerals as in FIG. 5 indicate the same components. 11 is a substrate. The substrate 11 is formed into a flat plate using a highly heat-resistant insulating material such as alumina porcelain, and has terminal electrodes 12 and 13 adhered to opposite ends thereof. In this embodiment, the terminal electrodes 12 and 13 are
Terminal portions 121 and 131, which are connected to the outside, are formed at both ends of the substrate 7 in the length direction so as to pass from the front surface to the side end surface and reach the back surface thereof, and these terminal portions 121 and 131
The pattern has lead electrode portions 122 and 132 extending inward from approximately the middle portion of the electrode.

The length l of the substrate 11 is the length of the yoke 4, the iron core 3,
When the acoustic transducer comprising the coil 2, permanent magnet 5, diaphragm 6 and case 1 is mounted on the board 11, at least the terminal parts 121 and 1
Set the length so that 31 is exposed to the outside.

During assembly, the yoke 4 is placed on the surface of the board 11.
The coil 2 is inserted into the iron core 3 set upright on the yoke 4, and the permanent magnet 5 is placed on the surface of the yoke 4 so as to surround the coil 2 and the iron core 3. A diaphragm 6 is attached to the upper end surface of the magnet 5.
is mounted, and furthermore, the case 1 is inserted from above so as to cover the permanent magnet 5. Substrate 11
In order to position the yoke 4 against the substrate 11
Holes 111 and 112 are formed approximately in the middle of the length l, and protrusions 43 and 44 (see FIG. 2) are formed on the bottom surface of the yoke 4 corresponding to the holes 111 and 112. 43 and hole 112 and protrusion 4
4 into each other. Thereby, the yoke 4 is reliably positioned at a predetermined position on the substrate 11. Then, during the assembly process, the coil terminal 2 of the coil 2
1 and 22 are provided in the yoke 4 and passed through the notches 41 and 42, etc., to the lead electrode parts 122 and 13 on the substrate 11.
Solder and fix to 2.

Incidentally, the case 1 may be fixed onto the surface of the substrate 11 by adhesive or mechanical coupling means such as hook fitting or screwing.

As described above, the acoustic transducer according to the present invention can be assembled by sequentially stacking the yoke 4, coil 2, permanent magnet 5, diaphragm 6, and case 1 on the surface of the substrate 11. Assembly work becomes much easier.

In addition, the items assembled as described above can be used for watches, cameras, microwave ovens, portable videos, etc.
When incorporating it into various devices such as a tape recorder or a pager, as shown in FIG.
6, the terminal portions 121, 13 of the terminal electrodes 12, 13
It is sufficient to place the terminals 1 in planar contact and solder them 17 and 18 by means such as solder reflow, eliminating the need for positioning and insertion of pin-shaped terminals, which were conventionally essential. In other words, it can be treated as a type of chip part, and like other chip parts,
The mounting work can be automated using an automatic mounting machine.

Furthermore, the terminal electrodes 12 and 13 are formed planarly on the heat-resistant substrate 11, and the weak point of conventional pin-shaped terminals is that the terminal mounting base is heated by solder heat, causing the terminal to become unstable and fall off. Since there is no room for such problems to occur, mechanical and electrical reliability is improved. Moreover, even if the substrate 11 is made thinner, the electrode terminal 1
The substrate 1 including the terminal electrodes 12 and 13 has no room for problems such as a decrease in the mounting strength of the terminal electrodes 12 and 13.
Since the entire device 1 is planar, the overall shape can be significantly reduced in size and thickness.

Effects of the invention As described above, the present invention provides an end electrode to the board on which the acoustic transducer is mounted to form a chip, which facilitates assembly, automounts the mounting process, and makes it smaller and thinner. An acoustic transducer can be provided.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of the acoustic transducer according to the present invention, FIG. 2 is a side sectional view thereof, FIG. 3 is an exploded perspective view thereof, and FIG. 4 is a printed circuit of the acoustic transducer according to the present invention. FIG. 5 is a sectional view showing a conventional example of an electrode type acoustic transducer. 1...Case, 2...Coil, 3...Iron core, 4
... Yoke, 5 ... Permanent magnet, 6 ... Vibration plate, 1
0...Sound emission hole, 11...Substrate, 12, 13...Terminal electrode.

Claims (1)

[Claims for Utility Model Registration] (1) An acoustic transducer is mounted on one surface of a substrate having a planar terminal electrode adhered to the end thereof, so that at least a part of the terminal electrode is exposed. . An acoustic transducer, characterized in that a lead wire of the acoustic transducer is conductively connected to the terminal electrode. (2) The acoustic transducer according to claim 1, wherein the terminal electrode is formed of a conductive film deposited on the substrate. (3) The acoustic transducer according to claim 1 or 2, wherein the terminal electrodes are formed on opposite ends of the substrate, respectively. (4) The acoustic transducer according to claim 1, 2, or 3, wherein the substrate is made of alumina porcelain. (5) The acoustic transducer according to claim 4, wherein the terminal electrode is a baked electrode. (6) A utility model registration characterized in that the acoustic transducer is configured to excite a diaphragm facing the iron core of the electromagnet with an air gap interposed therebetween through magnetic interaction between an electromagnet and a permanent magnet. An acoustic transducer according to claim 1, 2, 3, 4, or 5. (7) The electromagnet includes a flat yoke stacked on one surface of the substrate so that the terminal electrode is exposed, an iron core provided upright on one surface of the yoke, and an iron core inserted into the iron core. The permanent magnet is arranged on one surface of the yoke to surround the iron core and the coil, and the diaphragm is arranged so as to face the iron core with a gap between the permanent magnets. The acoustic transducer according to claim 6, characterized in that the acoustic transducer is peripherally supported at its end face. (8) The acoustic transducer according to claim 7, wherein a positioning protrusion and a hole that fit into each other are formed between the substrate and the yoke.