JP4073078B2 - Electromagnetic sound generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic sounding body that generates sound by vibrating a diaphragm with an electromagnet, and in particular, an electromagnetic sounding body having an electrode terminal structure that is small, thin, and attached with good workability when mounted on a printed circuit board or the like. About.
[0002]
[Prior art]
Along with the recent surface mounting of small electronic components, the surface mounting type in which an electromagnetic sounding body, which is a small buzzer, is directly mounted on a printed circuit board has become mainstream, and is often used for calling pagers such as mobile phones and pagers.
[0003]
As a conventional electromagnetic sounding body, the technology is disclosed in Japanese Patent Laid-Open No. 8-321670. FIG. 5 is a perspective view of an electromagnetic sounding body according to the prior art. In FIG. 5, the electromagnetic sounding body 20 includes a cylindrical case 21 in which a sounding member such as a yoke or a diaphragm is built, and a pair of electrode terminals 22 that extend obliquely downward from the upper surface of the case 21. Yes. The electrode terminal 22 is made of spring steel, stainless steel, or the like, and has a spring property as a whole. Further, the tip portion of the electrode terminal 22 extending downward is bent upward in a U-shape, and the outer surface of the bent portion 23 is elastically pressed against the wiring pattern formed on the printed circuit board. Further, the bent portion 23 of the electrode terminal 22 is provided with a protruding portion 24 at a portion that is pressed onto the wiring pattern formed on the printed circuit board.
[0004]
Next, FIG. 6 is a perspective view of an electromagnetic sounding body according to another prior art. In FIG. 6, the electromagnetic sounding body 30 includes a cylindrical case 31 in which a sounding member such as a yoke or a diaphragm is built, and a pair extending in the thickness direction from the upper surface of the case 31, as in the above-described prior art. It is comprised with the electrode terminal 32 which has this spring property. The electrode terminal 32 is curved above the case 31 and extends in a substantially U shape. And the protrusion part 33 is provided in the part which press-contacts on the wiring pattern formed in the U-shaped part on the printed circuit board.
[0005]
[Problems to be solved by the invention]
However, the two electromagnetic sounding bodies described above have the following common problems. That is, there is a very troublesome work of soldering one electrode terminal and one electrode terminal on the substrate of the sounding body. In addition, since the soldering is performed one by one, the positions and heights of the end portions of the electrode terminals are likely to be uneven. Further, since the substrate and the spring are processed separately, the members and the processing cost are high. In addition, the electrode terminal protrudes to the outer peripheral portion of the case, so that it is not suitable for mounting in a small space (FIG. 5). Moreover, the structure in which the thickness direction is thick is not suitable for thinning (FIG. 6). In addition, soldering requires two operations of soldering for terminal processing of the coil and soldering of the electrode terminals. There were various problems such as.
[0006]
The present invention has been made in view of the above-described conventional problems, and its purpose is to reduce costs by electrode terminal processing, fixing, coil terminal processing, etc., improve the positional accuracy of electrode terminals, and improve reliability by improving contactability. Thus, an electromagnetic type sounding body that can be mounted in a small space with a small and thin structure is provided.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an electromagnetic sound generator according to the present invention comprises a case main body having a sound emitting hole fixed to an upper case, a yoke housed in the case main body, and a central portion of the yoke. An iron core provided; an excitation coil disposed around the iron core; a magnet disposed on the yoke and around the excitation coil; and the magnet disposed inside the case body and the magnet A diaphragm arranged on the receiving surface of the case body, facing the magnet so as to form a magnetic circuit by the iron core, the yoke, and the excitation coil, and a terminal of the excitation coil are connected to connect to the outside. In the electromagnetic sounding body having an external connection terminal for the purpose, a housing recess for storing the external connection terminal is formed in the case body, and the external connection terminal is positioned in the storage recess. Has a deciding part, the external connection terminal consists of a pair of electrodes spring terminals, the electrode spring pin of the electrode spring pin and the positioning engaging portion engaged with the positioning portion formed in the accommodating recess A coil terminal connection portion formed at an end portion , and a pressure contact portion of the electrode spring terminal is provided with an electrode terminal having a spring property protruding from a housing recess of the case body, and the electrode spring terminal is The terminal of the exciting coil led out from the notch of the yoke is connected and fixed to the coil terminal connecting part of the electrode spring terminal by a fixing means while being engaged and fixed to the positioning part in the housing recess. is there.
[0008]
Further, the fixing portion of the solder, the coil end connecting part of the electrode spring pin and the terminal of the exciting coil, is characterized in that which has been subjected to silicone coating to protect the solid deposition section.
[0009]
The electrode spring terminal is characterized in that a protrusion is formed at a position where the wiring pattern of the printed circuit board is pressed.
[0010]
Moreover, fitting the electrode spring pin dowels for positioning formed in the accommodating recess, the head of the dowel, characterized in that the electrode spring pin by thermal caulking attached to the case body. In addition, the electrode spring terminal is fixed to the positioning portion formed in the outer portion of the housing body in the housing recess, and from the positioning portion toward the inside of the case body and in the housing recess in a plan view. The electrode terminals are formed so as to be disposed, and the positioning portions formed on the outer portion in the storage recess are respectively disposed on the opposing outer portions in the storage recess. It is characterized by being formed. The method of assembling the electromagnetic sound generator according to the present invention includes a case main body having an upper case and a lower case fixed to each other and having a sound emitting hole, a yoke housed in the case main body, and an iron core provided at a central portion of the yoke. An excitation coil arranged around the iron core, a magnet arranged around the yoke, and a magnet inside the case body that is magnetized by the magnet, the iron core, the yoke, and the excitation coil. An electromagnetic wave having a diaphragm arranged on the receiving surface of the case body and facing the magnet so as to form a circuit, and an external connection terminal for connecting the terminal of the excitation coil and connecting to the outside In the method of assembling the mold sound producing body, the case body has a positioning portion for positioning the pair of external connection terminals processed into a lead frame shape, and the lead frame is provided in the positioning portion. A step of engaging and fixing the external connection terminal having a shape, a step of fixing the end of the excitation coil derived from the notch portion of the yoke to the coil end connection portion of the external connection terminal, and protecting the end of the excitation coil A step of cutting near the position where the external connection terminal is positioned to form a single external connection terminal, and a step of forming a spring property for projecting the electrode terminal of the external connection terminal from the case body It is characterized by this.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The electromagnetic sound generator according to the present invention will be described below with reference to the drawings. 1 to 4 relate to an electromagnetic sounding body according to an embodiment of the present invention, and FIG. 1 is a plan view of the electromagnetic sounding body. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a right side view of FIG. 4 is a side view of the electromagnetic sounding body in FIG. 3 attached to a printed circuit board.
[0012]
1 and 2, reference numeral 15 denotes an electromagnetic sounding body. The electromagnetic sounding body 15 includes a sounding member such as a yoke or a diaphragm built in the case main body 1 and an electrode terminal 10 extending from the case main body 1 to the outside. The case main body 1 forms a sound emitting hole 1a by fixing the lower case 2 and the upper case 3 together. A yoke 4 made of a magnetic material is fixed to the lower case 2 with an epoxy adhesive 5. Sound generating members housed in the case main body 1 are an iron core 6 provided at the center of the yoke 4, a magnet 7 disposed around the yoke 4, and an inside of the case main body 1. The diaphragm 8 is disposed on the receiving surface of the lower case so as to face the magnet 7 so that a magnetic circuit is formed by the magnet 7, the iron core 6 and the yoke 4. An exciting coil 9 is disposed around the iron core 6. The lead frame-like electrode terminal 10 which is an external connection terminal for connecting the terminals 9a and 9b of the exciting coil 9 and connecting to the outside includes a pair of electrode spring terminals 10a and 10b. The lead frame-shaped electrode terminal 10 is a press-processed assembled lead frame-shaped electrode terminal instead of the conventional single electrode terminal, and a pair of single electrode springs by cutting described later. Terminals 10a and 10b are formed. On the electrode terminals of the electrode spring terminals 10a and 10b, projections (bumps) 10f and 10g are simultaneously formed at the positions where they are pressed against the wiring pattern of the printed circuit board, respectively, at the time of pressing.
[0013]
Dowels 2a (four places) projecting from the upper surface of the lower case 2, electrode spring terminal housing recesses 2b described later, and air escapes 2c are formed on the outer periphery of the upper surface. The dowel 2 a is fitted with a positioning hole 10 c formed in the lead frame electrode terminal 10, and the head of the dowel 2 a is heat caulked to fix the lead frame electrode terminal 10 to the lower case 2.
[0014]
Next, the terminals 9a and 9b of the exciting coil 9 derived from the two yoke notches 4a (three in FIG. 1) formed on the outer periphery of the yoke 4 are connected to the coil terminal connecting portions of the electrode spring terminals 10a and 10b. It is electrically connected to a certain end 10d, 10e by a fixing means such as solder 11.
[0015]
After the soldering, the coil is protected by applying a silicon coating 12 as a measure against disconnection of the soldered portion.
[0016]
Finally, the assembled lead frame-shaped electrode terminals 10 are cut in the vicinity of the protrusions 10f (parts B and C in FIG. 1) formed at positions where they are pressed against a wiring pattern of a printed circuit board, which will be described later. Terminals 10a and 10b are used. Thereafter, the protruding portions 10f and 10g formed on the electrode spring terminals 10a and 10b are biased so as to protrude from the lower case 2.
[0017]
As shown in FIG. 3, the pair of electrode spring terminals 10 a and 10 b described above are in a free state before being attached to the printed board, and the height from the upper surface of the lower case 2 to the protrusions 10 f and 10 g of the electrode spring terminals 10 a and 10 b. In FIG. 4, in the state after being attached to the printed board 13, in FIG. 4, the electrode spring terminals 10a and 10b enter into the recess 2b formed in the lower case 2, and the protrusions 10f and 10g The height is h2 from the upper surface of the lower case 2 and is extremely low. It is possible to minimize the increase in the thickness direction, and at the same time, the electrode spring terminals 10a and 10b are strongly pressed against the pattern of the printed circuit board 13 to ensure conduction. I can take it.
[0018]
Mounting space (width, height) by heat-caulking the above lead frame electrode terminals in the assembled state to the lower case, soldering the coil ends to the terminals, and taking measures such as disconnection with silicon coating Therefore, it is possible to obtain a low-cost surface-mount electromagnetic sounding body with high positional accuracy of the electrode terminals.
[0019]
【The invention's effect】
As is apparent from the above description, according to the present invention, the circuit board is not used, and the assembled lead frame-shaped electrode terminals are inexpensive. The two electrode terminal solders to the substrate and the terminal solder to the substrate of the coil are heat caulked for the electrode terminal and the coil is soldered directly to the electrode terminal, so that the processing cost can be reduced. The positional accuracy of the electrode terminal is improved and the contact reliability is improved. It is possible to provide an electromagnetic sounding body that is excellent in reliability, such as being small and thin and can be mounted in a small space, and has a large economic effect.
[Brief description of the drawings]
FIG. 1 is a plan view of an electromagnetic sounding body according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is a right side view of FIG. 1;
4 is a side view showing a state in which it is attached to the printed circuit board of FIG. 3; FIG.
FIG. 5 is a perspective view of a conventional electromagnetic sounding body.
FIG. 6 is a perspective view of another conventional electromagnetic type sounding body.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Case body 2 Lower case 2a Dowel 3 Upper case 4 Yoke 7 Magnet 8 Diaphragm 9 Excitation coil 9a, 9b Coil terminal 10 Lead frame-shaped electrode terminal 10a, 10b Electrode spring terminal 10c Positioning hole 10d, 10e End part 10f, 10g Protrusion (bump)
11 Solder 12 Silicon coating 13 Printed circuit board

Claims (7)

A case main body that has an upper case and a lower case and has a sound emitting hole, a yoke that is housed in the case main body, an iron core that is provided at the center of the yoke, and is disposed around the iron core A magnetic circuit is formed by the excitation coil, a magnet disposed on the yoke and around the excitation coil, and the magnet, the iron core, the yoke, and the excitation coil inside the case body. In addition, in an electromagnetic sounding body having a diaphragm disposed on the receiving surface of the case body, facing the magnet, and an external connection terminal for connecting a terminal of the exciting coil and connecting to the outside,
The case main body is formed with a storage recess for storing the external connection terminal, and has a positioning portion for positioning the external connection terminal in the storage recess,
The external connection terminal includes a pair of electrode spring terminals, and the electrode spring terminal is a coil terminal formed at a positioning engagement portion that engages with a positioning portion formed in the housing recess and an end portion of the electrode spring terminal. Having a connection part ,
And the pressure contact portion of the electrode spring terminal comprises an electrode terminal having a spring property protruding from the housing recess of the case body,
The electrode spring terminal is engaged and fixed to the positioning portion in the housing recess, and the terminal of the excitation coil derived from the notch portion of the yoke is connected to the coil terminal connection portion of the electrode spring terminal by a fixing means. Electromagnetic sound generator characterized by   2. The electromagnetic sound generation according to claim 1, wherein the coil terminal connecting part of the electrode spring terminal and the terminal of the exciting coil are provided with a silicon coating on the fixing part such as solder to protect the fixing part. body.   2. The electromagnetic sounding body according to claim 1, wherein a projection is formed at a position where the wiring pattern of the printed circuit board is pressed against the electrode terminal of the electrode spring terminal.   The electromagnetic spring according to claim 1, wherein the electrode spring terminal is fitted into a positioning dowel formed in the housing recess, the head of the dowel is caulked, and the electrode spring terminal is attached to the case body. Type sound generator.   The electrode spring terminal is fixed to the positioning portion formed at an outer portion in the housing recess of the case body, and is disposed in the housing recess from the positioning portion toward the inside of the case body and in plan view. The electromagnetic sounding body according to claim 1, wherein the electrode terminal is formed.   6. The electromagnetic sounding body according to claim 5, wherein the positioning portions formed in the outer portion in the storage recess are respectively formed in opposing outer portions in the storage recess. A case main body that has an upper case and a lower case and has a sound emitting hole, a yoke that is housed in the case main body, an iron core that is provided at the center of the yoke, and is disposed around the iron core An excitation coil, a magnet disposed around the yoke, and the magnet, and the magnet, the iron core, the yoke, and the excitation coil are opposed to the magnet so as to form a magnetic circuit. In the assembling method of the electromagnetic sounding body having the diaphragm disposed on the receiving surface of the case body and the external connection terminal for connecting the terminal of the exciting coil and connecting to the outside,
The case body has a positioning part for positioning the pair of external connection terminals processed into a lead frame shape,
A step of engaging and fixing the lead frame-shaped external connection terminal to the positioning portion; a step of fixing the terminal of the excitation coil derived from the notch portion of the yoke to the coil terminal connection portion of the external connection terminal; A step of protecting the end of the exciting coil, a step of cutting the vicinity of the external connection terminal to form a single external connection terminal, and a spring property of projecting the electrode terminal of the external connection terminal from the case body A method for assembling an electromagnetic sounding body comprising the steps of:

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