JP2008199116A - Electromagnetic transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an electromagnetic transducer which easily connects a coil pattern of a vibrating film and a connection terminal prepared in a frame without preparing a notch in a permanent magnet plate, and suppressing occurring of large stress in a connection part. <P>SOLUTION: The transducer is provided with: permanent magnet plates 2, 6 with magnetizing patterns in the plate surfaces; the vibrating film 4 which makes a meander line coil pattern 16 on the film surface face with the magnetizing pattern of the permanent magnet pattern 2, 6; buffer materials 3, 5 arranged in spaces between the permanent magnets plates 2, 6 and the vibrating film 4; a lower frame 1 and an upper frame 7 which laminate the permanent magnet plates 2, 6, the buffer materials 3, 5, and the vibrating film 4, cover, and support; and a terminal block 12 which is arranged in the lower frame 1, and performs external connection. The vibrating film 4 is provided with electrodes 17 which prepares end parts of the meander line coil pattern 16, are horizontally extended from edge ends of the film surface, and are connected to a connection terminal 11 which is comprised in the terminal block 12. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetic transducer that vibrates a vibrating membrane and reproduces sound such as an audio signal.

The electromagnetic transducer has a flat permanent magnet plate having a parallel striped multipole magnetized pattern in which strip-shaped N poles and S poles appear alternately, and a vibration film in which a coil pattern is formed on a resin film. And it is laminated | stacked with a buffer member etc., and is comprised.
When the current of the audio signal flows through the coil pattern of the diaphragm, the coil pattern and the multipolar magnetization pattern of the permanent magnet plate are electromagnetically coupled, and audio vibration is generated in the diaphragm in accordance with Fleming's law (for example, , See Patent Document 1). Such an electromagnetic transducer performs wiring connection between a coil pattern provided on the vibration film and the outside of the electromagnetic transducer using, for example, a connection terminal provided in the frame.

  FIG. 4 is an explanatory diagram showing a configuration of a conventional electromagnetic transducer. This figure is an exploded perspective view showing a configuration example of a conventional electromagnetic transducer. In this electromagnetic transducer, a permanent magnet plate 52 is mounted on a lower frame 51, a buffer member 53 is placed on the permanent magnet plate 52, a vibration film 54 is placed on the buffer member 53, and the vibration film 54 is placed on the vibration film 54. The buffer member 55 is placed, the permanent magnet plate 56 is mounted on the upper frame 57, and the lower frame 51 and the upper frame 57 are joined to form the permanent magnet plate 56 from above the buffer member 55. ing. Further, in the illustrated example, two terminal connection holes 62 penetrating the plate surface of the lower frame 51 are provided in the vicinity of the edge of the lower frame 51.

  The lower frame 51 and the upper frame 57 are formed in such a dimension that a clearance of about several millimeters is generated with respect to the peripheral portions of the permanent magnet plates 52 and 56. In order to connect the end portion of the coil pattern 64 provided on the vibration film 54 to the connection terminal 60, a substantially T-shaped cut is made in the edge portion of the vibration film 54, and the cut portion is bent so as to be widened. Two tongue-like pieces protrude below the vibration film 54. An end portion of the coil pattern 64 is disposed on the tongue-shaped piece, and this portion is provided as the electrode 63 of the vibration film 54. Further, since the electrode 63 protrudes below the diaphragm 54 and is connected to the connection terminal 60 in this way, the permanent frame disposed between the lower frame 51 including the connection terminal 60 and the diaphragm 54 as described later. The magnet plate 52 is provided with a notch 65 so as not to block between the electrode 63 and the connection terminal 60, and the buffer member 53 is provided with a notch 66.

FIG. 5 is a cross-sectional view of a conventional electromagnetic transducer. This figure shows a longitudinal section of the portion along the line BB ′ shown in FIG. 4. The same reference numerals are used for the same portions as those shown in FIG. 4, and the description thereof is omitted.
As described above, the permanent magnet plate 52 is placed on the lower frame 51, and the buffer member 53 and the vibration film 54 are placed. A terminal plate 61 is attached to the terminal connection hole 62 provided in the lower frame 51 from below the lower frame 51. In this attachment, the protruding portion of the connection terminal 60 fixed to the terminal plate 61 is inserted into the terminal connection hole 62 and exposed on the plate surface of the lower frame 51. As described above, the electrode 63 of the vibration film 54 protruding downward is fixed to the exposed portion by the solder 70 so that the coil pattern 64 and the connection terminal 60 are connected.

Japanese Patent Laid-Open No. 9-331596 (pages 3 to 5, FIGS. 1 and 2)

Since the conventional electromagnetic transducer is configured as described above, a notch is provided in a part of the permanent magnet plate disposed between the vibration film and the connection terminal, and the vibration is passed through the electrode of the vibration film. The coil pattern of the film was connected to the connection terminal. Alternatively, an external connection cable is directly connected to the end of the coil pattern. For this reason, a wiring space must be secured inside the electromagnetic converter, and the assembling workability is remarkably deteriorated and the defect occurrence rate is high.
Further, as described above, if a part of the permanent magnet plate is cut out, the vibration film cannot be vibrated efficiently, resulting in a decrease in generated sound pressure.
In addition, the cut portion provided in the vibration film is bent approximately 90 degrees to form an electrode, and this electrode is connected and fixed to the connection terminal. Therefore, stress is generated in the bent portion, and the vibration is adversely affected. There was a problem that a defect occurred in the fixed part.

  The present invention has been made in order to solve the above-described problems. The coil pattern and the frame of the vibrating membrane are provided without providing a notch in the permanent magnet plate and suppressing a large stress from being generated in the connection portion. It is an object of the present invention to obtain an electromagnetic transducer that can be easily connected to a connection terminal provided on the device.

  The electromagnetic transducer according to the present invention has an end portion of the coil pattern on the vibrating membrane, extends horizontally from the edge of the membrane surface, and connects the end portion of the coil pattern to the connection terminal provided on the terminal plate. A connection part is provided.

  According to the present invention, the diaphragm is provided with the connection portion that has the end portion of the coil pattern and extends horizontally from the edge of the film surface and connects the end portion of the coil pattern to the connection terminal provided on the terminal plate. Therefore, there is an effect that connection workability between the diaphragm and the connection terminal is improved.

An embodiment of the present invention will be described below.
Embodiment 1 FIG.
FIG. 1 is an explanatory diagram showing a configuration of an electromagnetic transducer according to Embodiment 1 of the present invention. This figure is an exploded perspective view of the electromagnetic transducer according to the first embodiment. When the lower frame 1 and the upper frame 7, and when the lower frame 1 and the upper frame 7 are joined, they are covered and supported by the permanent magnet. An arrangement configuration of the plates 2 and 6, the buffer members 3 and 5, and the vibration film 4 is shown.
The lower frame 1 and the upper frame 7 are made of, for example, iron plate made of a ferromagnetic material by sheet metal processing. When the flat lower frame 1 is joined to the upper frame 7, a substantially rectangular box-shaped frame is formed. The upper surface and the bottom surface of the frame are formed in a rectangular shape. A permanent magnet plate 2 is attached to the lower frame 1 by its own magnetic force. A buffer member 3 is stacked above the permanent magnet plate 2 in the drawing, and a vibration film 4 is stacked above the buffer member 3. A buffer member 5 is overlaid on the vibrating membrane 4, and a permanent magnet plate 6 is overlaid thereon. The permanent magnet plate 6 is mounted on the inner upper surface of the box-shaped upper frame 7 by its own magnetic force.

  The lower frame 1 is formed in a flat plate shape, and includes a terminal plate 12 having connection terminals 11 in the vicinity of, for example, a short side of a quadrilateral plate shape. Two connection terminals 11 are provided so as to be connected to electrodes 17 described later, and are fixed to a terminal plate 12 made of an insulating material. The terminal plate 12 is mounted on the upper surface of the lower frame 1, that is, on the inner surface of the lower frame 1 which is the inner side when the lower frame 1 and the upper frame 7 are joined, and the distal end portion of the connection terminal 11 is the lower frame. It is installed so as to protrude outward from the edge of 1. The connection terminal 11 is provided with a resist coating having an insulating property at least at a portion where there is a possibility of contact so as not to contact with the lower frame 1 and the upper frame 7 to cause a short circuit.

  Further, the permanent magnet plate 2 is mounted behind the terminal plate 12 installed at the edge of the lower frame 1 as described above. That is, the lower frame 1 is configured with dimensions that allow the terminal plate 12 and the permanent magnet plate 2 to be arranged on the same plane. The upper frame 7 is also configured to have a size that covers each component member such as the vibration film 4 including the terminal plate 12 attached to the lower frame 1 by being joined to the lower frame 1. Thus, the dimensions of the plate surface of the lower frame 1 and the upper surface of the upper frame 7 are as follows: the film surface of the vibration film 4, the plate surfaces of the permanent magnet plates 2 and 6 that are laminated with the vibration film 4, and the buffer. The members 3 and 5 are configured to be larger than the upper and lower surfaces. The plate surfaces of the permanent magnet plates 2 and 6 described here, the upper and lower surfaces of the buffer members 3 and 5, and the film surface of the vibration film 4 correspond to the shapes of the lower frame 1 and the upper frame 7, for example, It is formed in a rectangle.

  The vibration film 4 has a conductor pattern on a resin film 15 such as polyimide like a general flexible substrate. This conductor pattern is formed by meandering a single pattern line over substantially the entire surface of the resin film 15, for example, forming a meandering pattern in which a long linear portion is provided in the longitudinal direction of the rectangular vibration film 4, It is configured to act as an electromagnetic coil. Hereinafter, this conductor pattern is referred to as a meandering coil pattern 16. Further, the vibration film 4 includes two electrodes 17 each having an end portion of a meandering coil pattern 16 as a connection portion with the terminal plate 12.

The electrode 17 is provided flush with the film surface of the vibration film 4, and is configured as a tongue-like piece of the quadrilateral vibration film 4 as shown in FIG. 1, for example, and has a meandering coil pattern 16. It is integrally formed with the surface and extends horizontally from the edge of the membrane surface. As described above, the electrodes 17 serving as the end portions of the meandering coil pattern 16 are disposed at substantially both ends of one short side, for example, of the edge of the vibration film 4. It protrudes in the extending direction. The positions where the electrodes 17 are provided are preferably four corners of the film surface having the meandering coil pattern 16 in order to suppress the influence on the vibration of the vibration film 4, and the width of the tongue shape is set so as not to affect the vibration.
Further, the electrode 17 has an appropriate amount of protrusion from the edge so that it can be connected to each of the two connection terminals 11 provided at the end of the lower frame 1 when the electromagnetic transducer is assembled. Is provided. In addition, this protrusion amount is set so that the electrode 17 bends appropriately when the electrode 17 is connected and fixed to the connection terminal 11 of the terminal plate 12 as described later, and the arrangement of the vibrating membrane 4 and the arrangement of the connection terminal 11 are set. Even when there is a slight level difference, the connection can be made satisfactorily.

The permanent magnet plates 2 and 6 are made of, for example, plate-like sintered ferrite magnets, and these two magnet plates are configured in the same shape and size. The permanent magnet plates 2 and 6 are formed in a shape and size that can be superimposed on a portion of the vibrating membrane 4 where the meandering coil pattern 16 is provided, that is, on all portions of the vibrating membrane 4 that actually vibrate. .
The plate surfaces of the permanent magnet plates 2 and 6 have strip-shaped magnetized portions extending in the longitudinal direction. This magnetized portion is provided in the form of parallel stripes in which S poles and N poles are alternately arranged. Hereinafter, this magnetized portion is referred to as a multipolar magnetized pattern. The permanent magnet plate 2 is provided with a plurality of sound radiation holes 13 at positions avoiding the multipolar magnetization pattern, and similarly, the permanent magnet plate 6 is provided with a plurality of sound radiation holes 14.

As described above, the permanent magnet plate 2 attached to the lower frame 1 is mounted on the upper surface of the lower frame 1 together with the terminal plate 12. The vibration film 4 laminated on the permanent magnet plate 2 or the like is configured to connect the electrode 17 projecting horizontally from the edge thereof to the terminal plate 12, so that the permanent magnet plate 2 or the like is connected to the lower frame 1. Are arranged next to each other so as not to overlap the terminal plate 12. That is, the permanent magnet plate 2 and the like do not need to be provided with notches or the like for avoiding contact with the terminal plate 12, so that the permanent magnet plate 2 and the permanent magnet plate 6 are configured in the same shape, And it forms so that it can laminate | stack on the whole film surface which has the meandering coil pattern 16 of the vibration film | membrane 4, and it is comprised so that a multipolar magnetization pattern may oppose all over the said film surface.
As described above, the permanent magnet plate 6 is laminated above the buffer member 3, the vibration film 4, the buffer member 5, and the permanent magnet plate 2 mounted on the lower frame 1, and when these are laminated. Specifically, it is mounted on the inner side of the upper frame 7 so that the same poles face each other so that its own multipole magnetization pattern overlaps the multipole magnetization pattern of the permanent magnet plate 2.

  The upper frame 7 is formed of a sheet metal such as an iron plate as described above, and includes a sound radiation hole 18 communicating with the sound radiation hole 14 of the permanent magnet plate 6 on the upper surface thereof when the permanent magnet plate 6 is mounted. ing. The lower frame 1 and the upper frame 7 are each provided with, for example, a concave or convex fitting portion. When the lower frame 1 and the upper frame 7 are joined, It is comprised so that it may be joined and fixed.

  FIG. 2 is a cross-sectional view showing the configuration of the electromagnetic transducer according to the first embodiment. This figure shows a longitudinal section along the line A-A 'shown in FIG. 1, and the same reference numerals are used for the same parts as those shown in FIG. 1, and the description thereof is omitted. As described above, the permanent magnet plate 2 is attached to the lower frame 1 by its own magnetic force, and the permanent magnets so that the sound radiation holes 18 of the upper frame 7 and the sound radiation holes 14 of the permanent magnet plate 6 communicate with each other. The plate 6 is positioned, and the permanent magnet plate 6 is attached to the upper frame 7 by its own magnetic force. Thus, the lower frame 1 and the upper frame 7 on which the permanent magnet plates 2 and 6 are mounted act as yoke materials for the permanent magnet plates 2 and 6.

  A buffer member 3 is stacked on the upper surface of the permanent magnet plate 2 mounted on the lower frame 1, and a vibration film 4 is further stacked thereon to stack a buffer member 5. When the upper frame 7 is joined to the lower frame 1, the permanent magnet plate 6 is disposed on the buffer member 5, and the diaphragm 4 is interposed between the permanent magnet plate 2 and the permanent magnet plate 6 via the buffer members 3 and 5. Be placed. Thus, when each part is arrange | positioned, the part which the vibration film 4 actually vibrates, ie, the part provided with the meandering coil pattern 16, is the permanent magnet plate 2 and the permanent magnet plate 6 via the buffer members 3 and 5. It is sandwiched between. Further, the electrode 17 of the vibration film 4 is not sandwiched between the permanent magnet plates 2 and 6 and the buffer members 3 and 5 from above and below, in other words, the permanent magnet plate 2, the buffer member 3, the vibration film 4, the buffer member 5, And when the permanent magnet plate 6 is laminated | stacked, it protrudes from the side part, and is soldered to the connecting terminal 11 with the solder 20, for example. In this way, the electrode 17 is connected and fixed to the connection terminal 11, whereby the arrangement position of the vibration film 4 is maintained. The vibration film 4 is fixed by attaching a tape to the buffer members 3 and 5 so that the position of the vibration film 4 does not shift, or the vibration film 4 is provided with a protrusion protruding from the edge, so that the lower frame 1 and the upper frame When joining 7, the position may be fixed by sandwiching the protrusion between them.

  FIG. 3 is an explanatory diagram showing a configuration of a vibration membrane of a general electromagnetic transducer. This figure shows an embodiment in which a T-shaped cut C is formed in the vibrating membrane 54 and bent downward to open this portion to form the electrode 63. The vibration film 54 has a coil pattern 64 similar to the meandering coil pattern 16 of the vibration film 4 shown in FIG. 1 and the like, and is configured such that the end of the coil pattern 64 becomes the electrode 63 described above. . As shown in FIG. 3, when the notch 66 is provided in the buffer member 53 and the notch 65 is provided in the permanent magnet plate 52 so that the vibration film 54 is laminated on the buffer member 53 and the permanent magnet plate 52, The electrode 63 bent as described above is connected to, for example, the connection terminal 60 installed on the lower frame 51 so as not to interfere with the bent electrode 63. When configured in this manner, the electrode 63 is bent by approximately 90 degrees with respect to the film surface of the vibration film 54. Therefore, when the electrode 63 is connected and fixed to the connection terminal 60 using, for example, solder, stress is generated in the bent portion. In addition, there is a problem that the vibration of the vibration film 54 is adversely affected and the connection fixing portion is likely to be deteriorated or broken.

  The electromagnetic transducer shown in FIG. 1 and FIG. 2 is a connection terminal arranged in the extending direction of the electrode 17 for connecting the electrode 17 to the connection terminal 11 as described above, that is, without bending the electrode 17. Since it is soldered to 11, it can be connected and fixed without causing a great stress. Further, since the permanent magnet plates 2 and 6 can be arranged avoiding interference such as overlapping with the terminal plate 12 in the vertical direction, all the plate surfaces having the multipolar magnetization pattern of the permanent magnet plates 2 and 6 can be used. It can be made to oppose to the meandering coil pattern 16 so as to overlap the vibration film 4. As a result, the electromagnetic coupling between the permanent magnet plates 2 and 6 and the diaphragm 4 can be satisfactorily performed, and sound reproduction can be performed with a high sound pressure.

As described above, according to the first embodiment, the diaphragm 4 is provided with the tongue-like electrode 17 that protrudes in the horizontal direction from substantially both ends of one side of the diaphragm 4 and is provided with the end of the meandering coil pattern 17. Since the electrode 17 is connected and fixed to the connection terminal 11 of the terminal plate 12 arranged at the end of the lower frame 1, the connection between the electrode 17 of the vibration film 4 and the connection terminal 11 of the terminal plate 12 is performed. It becomes easy and there is an effect that connection workability can be remarkably improved.
Moreover, it is not necessary to form the permanent magnet plate 2 attached to the lower frame 1 and the permanent magnet plate 6 attached to the upper frame 7 into different shapes by using two cutting molds, and using one cutting mold. There is an effect that the permanent magnet plates 2 and 6 can be formed.
Further, all the surfaces of the permanent magnet plates 2 and 6 having the multipolar magnetization pattern can be used for electromagnetic coupling with the vibration film 4 without being cut out. Therefore, there is an effect that the sound pressure level generated can be improved, and the unnecessary vibration disturbance is eliminated, so that the sound quality can be improved.

  The electromagnetic transducer according to the first embodiment is configured such that the terminal plate 12 is disposed inside the lower frame 1 and the upper frame 7 when the lower frame 1 and the upper frame 7 are joined. By appropriately setting the protruding amount, the terminal plate 12 is not necessarily limited to the configuration in which the lower frame 1 and the upper frame 7 are joined.

It is explanatory drawing which shows the structure of the electromagnetic transducer by Embodiment 1 of this invention. 1 is a cross-sectional view illustrating a configuration of an electromagnetic transducer according to Embodiment 1. FIG. It is explanatory drawing which shows the structure of the diaphragm of a general electromagnetic transducer. It is explanatory drawing which shows the structure of the conventional electromagnetic transducer. It is sectional drawing which shows the structure of the conventional electromagnetic transducer.

Explanation of symbols

  1,51 Lower frame, 2, 6, 52, 56 Permanent magnet plate, 3, 5, 53, 56 Buffer member, 4,54 Vibration membrane, 7, 57 Upper frame, 11, 60 Connection terminal, 12, 61 terminal Plate, 13, 14, 18 Sound radiation hole, 15 Resin film, 16, 64 Meander coil pattern, 17, 63 Electrode, 20, 70 Solder, 62 Terminal connection hole, 65, 66 Notch, C Notch.

Claims (4)

A permanent magnet plate having a magnetized pattern on the plate surface, a vibration film having a coil pattern on the film surface opposed to the magnetized pattern of the permanent magnet plate, and a buffer disposed in the gap between the permanent magnet plate and the vibration film In an electromagnetic transducer comprising: a member; a frame that covers and supports the permanent magnet plate, the buffer member, and the vibration film; and a terminal plate that is disposed on the frame and performs external connection.
The vibration film includes a connection portion that has an end portion of the coil pattern and extends horizontally from the edge of the film surface and connects the end portion of the coil pattern to a connection terminal provided on the terminal plate. An electromagnetic transducer.   The electromagnetic transducer according to claim 1, wherein the connecting portion protrudes in a tongue shape to form a coil pattern electrode.   The electromagnetic transducer according to claim 1, wherein the connection portion is soldered to the connection terminal to hold the position of the vibration film.   4. The electromagnetic transducer according to claim 1, wherein the permanent magnet plate is formed so as to face the entire film surface having the coil pattern of the vibration film. 5.

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