JP2008099106A - Speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a frame used for a speaker to prevent the speaker from being damaged. <P>SOLUTION: The speaker comprises a magnetic circuit body 11, a voice coil 16 disposed freely movably to a magnetic gap 15 that the magnetic circuit body 11 forms, a diaphragm 19 having an inner peripheral end portion connected to the voice coil 16, a metal frame 20 which has an outer peripheral portion connected to an outer peripheral end portion of the diaphragm 19 and supports the magnetic circuit body 11 at an inner peripheral portion, and a resin frame 21 formed integrally at the outer peripheral portion of the metal frame 20 by insert molding. The resin frame 21 has a cut portion formed in a portion of a joining portion for the metal frame 20, and consequently cracking of the resin frame 21 provided to be formed in an arbitrary shape corresponding to a fitting place can be suppressed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a speaker.

  The conventional invention will be described below with reference to FIG.

  As shown in FIG. 4, the conventional speaker 1 includes a magnetic circuit body 5 configured by sandwiching a cylindrical magnet 2 between a lower plate 3 having a center pole and a cylindrical upper plate 4. The magnetic circuit body 5, the voice coil 7 movably disposed with respect to the magnetic gap 6 formed by the magnetic circuit body 5, and the diaphragm 8 having an inner peripheral end connected to the voice coil 7, A metal frame 9 having an outer peripheral portion connected to an outer peripheral end portion of the diaphragm 8 via an edge 8A and supporting the magnetic circuit body 5 at the inner peripheral portion, and insert molding on the outer peripheral portion of the metal frame 9 The speaker 1 is composed of the resin frame 10 formed integrally with the resin frame 10.

  This conventional speaker 1 is provided with a resin frame 10 having a strength that is sufficient to support a heavy magnetic circuit body 5 at the outer peripheral end of a metal frame 9 that is inferior in strength to the metal frame 9 but excellent in moldability. It has a structure. That is, the speaker frame 1 can be attached to various places by molding the resin frame 10 into any appropriate shape according to the place of attachment.

For example, Patent Document 1 is known as a prior art document relating to the invention of this application.
JP 2002-152883 A

  In the conventional speaker 1, when an audio signal is applied to the voice coil 7, a driving force is generated in the voice coil 7 by the action of the magnetic force of the magnet 2, and the diaphragm 8 connected to the voice coil 7 by this driving force. This is a mechanism that generates sound by vibrating the. However, when an audio signal is applied to the voice coil 7, Joule heat is generated in the voice coil 7 together with the driving force, and this heat is transmitted to the metal frame 9 through the magnetic circuit body 5 and to the metal frame 9. Heat is conducted to the resin frame 10 provided on the outer peripheral portion of the metal frame 9. Here, since the resin frame 10 provided for the purpose of mounting the speaker 1 has a different coefficient of thermal expansion from that of the metal frame 9, there is a difference in thermal expansion between the metal frame 9 and the resin frame 10 as the temperature changes. Arise. Due to this difference in thermal expansion, thermal stress is generated in the resin frame 10, and as a result, cracks may occur in the resin frame 10 and the speaker 1 may be damaged.

  Accordingly, an object of the present invention is to provide a speaker frame that prevents damage to the speaker.

  In order to achieve this object, according to the present invention, a notch portion is provided in a part of the joint portion between the resin frame and the metal frame.

  With the above configuration, the thermal stress generated due to the difference in thermal expansion between the metal frame and the resin frame is absorbed by the notch provided at the joint between the metal frame and the resin frame. Thereby, generation | occurrence | production of the crack in a resin frame can be suppressed, and damage to a speaker can be prevented.

(Embodiment 1)
Hereinafter, Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 is a sectional view showing a speaker of the present invention. The upward direction is the direction A in FIG.

  As shown in FIG. 1, the magnetic circuit body 11 is configured by sandwiching a cylindrical magnet 14 from above and below between a cylindrical upper plate 12 and a lower plate 13 having a center pole. The magnetic circuit body 11 forms a cylindrical magnetic gap 15 from the outer peripheral side surface of the center pole of the lower plate 13 to the inner peripheral side surface of the upper plate 12.

  A cylindrical voice coil 16 is disposed in the magnetic gap 15 with a gap between the center poles of the upper plate 12 and the lower plate 13. The voice coil 16 is arranged so as to be movable in the vertical direction with respect to the magnetic gap 15, and a dust cap 17 is provided on the upper part of the voice coil 16 to prevent dust from entering. The outer peripheral side surface of the voice coil 16 is connected to the inner peripheral end of the damper 18, and the damper 18 supports the voice coil 16 so as to be movable up and down.

  Further, the inner peripheral end portion of the diaphragm 19 is connected to the outer peripheral side surface above the damper 18 connecting portion of the voice coil 16, and the diaphragm 19 vibrates due to the vertical movement of the voice coil 16. ing.

  In addition, the configuration of the metal frame 20 and the resin frame 21 in Embodiment 1 of the present invention will be described with reference to FIGS. 1, 2A, 2B, and 3. FIG. 2A is a configuration perspective view of the metal frame 20 and the resin frame 21 of the present invention, FIG. 2B is an enlarged view of the notch 22 of the present invention, and FIG. 3 is the metal frame 20 and the resin frame of the present invention. FIG.

  As shown in FIG. 1, the opening edge of the metal frame 20 is connected to the outer peripheral end of the diaphragm 19 via the edge 19 </ b> A, and the inner peripheral is connected to the upper surface of the upper plate 12 constituting the magnetic circuit body 11. Has been. The resin frame 21 formed in a ring shape is integrally formed with the metal frame 20 by insert molding. As shown in FIGS. 1 and 2A, the inner peripheral portion of the resin frame 21 is the outer peripheral portion of the metal frame 20. It is connected to the. This resin frame 21 is provided for the purpose of attaching the speaker 1 to various places, and in order to enable molding into any appropriate shape according to the place of attachment, a resin material that has better moldability than a metal material It is composed of. As shown in FIGS. 2A, 2B, and 3, the resin frame 21 is provided with a notch 22 having a substantially arc shape at the left and right ends of the lower end, and this notch 22, the upper surface portion, the lower surface portion, and the outer peripheral end side surface of the metal frame 20 are exposed portions that are not covered with the resin frame 21. Further, the metal frame 20 is provided with a hole 23 in a portion covered with the resin frame 21, and the hole 23 is formed when the metal frame 20 and the resin frame 21 are integrally formed by insert molding. 21 is filled with a resin material.

  Next, the operation of the speaker according to Embodiment 1 of the present invention will be described with reference to FIG. 1, FIG. 2, and FIG.

  When an audio signal is applied to the voice coil 16 shown in FIG. 1, it reacts with the magnetic flux in the magnetic gap 15 formed by the magnetic circuit body 11, and a driving force is generated in the voice coil 16 by the principle of electromagnetic action. At this time, the driving direction follows the Fleming left-hand rule, and the voice coil 16 varies in the vertical direction. Due to the fluctuation of the voice coil 16, the diaphragm 19 connected to the voice coil 16 vibrates, and sound is emitted from the speaker by moving the air.

  Further, when an audio signal is applied to the voice coil 16 in this way, heat is generated, and the heat is transmitted from the magnetic circuit body 11 to the metal frame 20 and the resin frame 21. At this time, since the resin frame 21 made of a resin material has a thermal conductivity different from that of the metal frame 20 made of a metal material, the resin frame 21 is subjected to thermal stress with a change in temperature, resulting in cracks. May occur and the speaker may be damaged.

  Therefore, in the first embodiment of the present invention, as shown in FIGS. 2 and 3, the resin frame 21 integrally formed by insert molding is provided with a notch 22 at a joint portion with the metal frame 20. According to this configuration, the notch 22 can absorb the thermal stress generated in the resin frame 21 due to the difference in thermal expansion from the metal frame 20. Thereby, the resin frame 21 is not cracked, and as a result, damage to the speaker can be prevented. A plurality of notches 22 may be provided. This is because the effect of absorbing thermal stress is increased by providing a plurality of notches 22.

  In addition, it is desirable that the left and right ends of the lower end portion of the cutout portion 22 provided in the resin frame 21 have a substantially arc shape. Thus, by making the left and right ends of the lower end of the notch 22 substantially arc-shaped, the thermal stress acting in the tangential direction of the generally ring-shaped resin frame 21 is dispersed, and cracks are generated from the notch 22. Can be prevented. What is important here is that the notch portion 22 does not have an angle at which thermal stress concentrates and becomes the starting point of cracking, that is, the left and right ends of the lower end portion of the notch portion 22 are formed in a substantially arc shape. Instead, the shape of the notch 22 may be a substantially semi-elliptical shape.

  In addition, since the resin frame 21 receives thermal stress from a portion in contact with the outer peripheral portion of the metal frame 20, the upper and lower surfaces of the metal frame 20 are notched at the notch 22 in order to absorb the thermal stress generated in the resin frame 21. Further, it is more effective if the outer peripheral end side surface is an exposed structure not covered with the resin frame 21. That is, in this configuration, the lower end portion of the cutout portion 22 is located below the outer peripheral end portion of the metal frame 20.

  In the first embodiment of the present invention, since the notch 22 is provided in the resin frame 21, the bonding area between the metal frame 20 and the resin frame 21 is reduced, and as a result, the bonding strength between the metal frame 20 and the resin frame 21 is reduced. May be weakened. Therefore, in order to ensure the bonding strength between the resin frame 21 and the metal frame 20, a hole 23 may be provided in a portion where the metal frame 20 is covered with the resin frame 21 as shown in FIG. 3. Thus, by performing insert molding in a state where the hole 23 is provided in the metal frame 20, the resin material constituting the resin frame 21 is filled in the hole 23 provided in the metal frame 20, and the hole 23 is provided. This is because the continuity between the metal frame 20 and the resin frame 21 is increased and the bonding strength is ensured as compared with the case where there is not.

  In the first embodiment of the present invention, the speaker having the outer magnetic type magnetic circuit body 11 is shown. However, the present invention is not limited to this, and the present invention can be applied to a speaker having an inner magnetic type magnetic circuit body. good.

  Moreover, since the door part of a car receives a strong impact at the time of opening / closing and running, the vehicle-mounted speaker attached to the door part may fall off if the bonding strength with the attachment part is weak. In addition, in-vehicle speakers are often exposed to high temperature conditions such as actual use door mounting and rear panel mounting. Therefore, the present invention can maintain the bonding strength with the mounting portion of the speaker by suppressing the occurrence of cracks due to the thermal expansion difference between the metal frame 20 and the resin frame 21, and can prevent the speaker from falling off the mounting portion. It can be suitably used for a vehicle-mounted speaker.

  In the field of audio systems, speakers tend to be smaller and lighter and have large inputs. Originally, in the case of a large input, it is necessary to increase the diameter of the voice coil 16 in proportion to the input, but it cannot be larger than the price problem in the actual situation. When a large input is applied to the loudspeaker having such a configuration, the voice coil 16 generates Joule heat in proportion to it, and the difference in thermal expansion between the metal frame 20 and the resin frame 21 appears remarkably. At this time, if it is this invention, generation | occurrence | production of a thermal stress can be suppressed and damage to a speaker can be prevented. Therefore, the present invention can be suitably employed in an audio system.

  INDUSTRIAL APPLICABILITY The present invention can prevent the speaker from being damaged by absorbing the thermal stress of the frame in the notch provided in the frame, and is particularly useful for a speaker for in-vehicle use or an audio system.

Sectional drawing of the speaker in Embodiment 1 of this invention (A) is a perspective view of the metal frame and resin frame part in Embodiment 1 of this invention, (B) is an expansion perspective view of the notch part of the speaker frame in Embodiment 1 of this invention. The enlarged plan view of the junction part of the metal frame 20 and the resin frame 21 in Embodiment 1 of this invention Cross-sectional view of a conventional speaker

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Magnetic circuit body 12 Upper plate 13 Lower plate 14 Magnet 15 Magnetic gap 16 Voice coil 17 Dust cap 18 Damper 19 Diaphragm 19A Edge 20 Metal frame 21 Resin frame 22 Notch part 23 Hole

Claims (4)

A magnetic circuit body, a voice coil movably disposed with respect to a magnetic gap formed by the magnetic circuit body, a diaphragm having an inner peripheral end connected to the voice coil, and an outer peripheral end of the diaphragm And a resin frame integrally formed on the outer periphery of the metal frame by insert molding, and the resin frame is one of the joint portions with the metal frame. A speaker characterized in that a notch is provided in the part. The speaker according to claim 1, wherein the left and right sides of the lower end portion of the notch are substantially arc-shaped. The speaker according to claim 1 or 2, wherein a metal frame is exposed at the cutout portion. The speaker according to claim 1, wherein a hole is provided in a portion of the metal frame covered with the resin frame.

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