JPH0582195U - In-vehicle speaker system - Google Patents

Abstract

(57) [Abstract] [Purpose] Regarding a speaker system used for an on-vehicle audio system, a pressure difference between a vehicle interior and a back cavity caused by opening and closing a door or the like causes damage or characteristics of a vibration system of the speaker system. An object of the present invention is to prevent deterioration and to prevent an abnormal increase in the low frequency range caused by the so-called baffle effect to realize a flat sound pressure frequency characteristic in the vehicle interior. In a system in which a back cavity is provided on the back surface of a speaker unit mounted on an automobile, a back cavity 6 on the back surface of the speaker unit 1 and a passenger compartment 5 are provided.
And a ventilation hole 7 is provided between and. Further, the ventilation hole 7 is formed in the speaker unit 1 itself or in the vicinity of the speaker unit 1, and is configured so as to function as a high-pass filter at an acoustic low frequency band.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a speaker system used for an on-vehicle audio system.

[0002]

[Prior Art]

 As shown in FIG. 8, the rear speaker 1 of a passenger car is often mounted on the rear tray 2 to utilize the trunk room as a back cavity. In this figure, 3 is a trunk lid and 4 is a rear glass.

When the trunk room is used as a back cavity in this way, the sound on the back surface of the speaker unit wraps around the inside of the vehicle compartment, causing deterioration of the low-frequency reproduction band. Therefore, in the past, the acoustic isolation between the trunk room and the passenger compartment was performed.

[0004]

[Problems to be solved by the device]

 However, in recent years, due to improvements in the quality and mounting technology of automobile parts, the airtightness has been improved, and the airtightness between the trunk room and the passenger compartment has been perfected, resulting in another problem.

That is, when the door of the passenger compartment is opened or closed, or when the passenger compartment is opened or closed, a large pressure difference is generated between the passenger compartment and the passenger compartment, and the diaphragm of the speaker unit 1 mounted on the rear tray 2 is vibrated. Excessive pressure is applied to. Therefore, problems such as the diaphragm being damaged and the characteristics of the speaker being gradually deteriorated due to repeated application of large stress have occurred.

Further, since the so-called baffle effect is large in the vehicle interior, if the degree of airtightness with the trunk room is increased, the sound pressure frequency characteristics of the speaker unit in the free sound field are flat, but the playback frequency is flat in the vehicle interior. The problem is that the characteristics cannot be obtained and the sound pressure emitted from the speaker unit in the low frequency range rises abnormally.

The technical problem of the present invention is to pay attention to such a problem, and due to the pressure difference between the vehicle interior and the back cavity caused by opening and closing of a door or the like, the vibration system of the speaker system is damaged or its characteristics are deteriorated. It is intended to prevent the occurrence of noise and to prevent the abnormal increase in the low frequency range caused by the so-called baffle effect to realize a flat vehicle interior sound pressure frequency characteristic.

[0008]

[Means for Solving the Problems]

 FIG. 1 is a schematic cross-sectional view illustrating the basic principle of a vehicle-mounted speaker system according to the present invention. Reference numeral 1 is a speaker unit, which is mounted toward the interior 5 of the automobile. The back surface 6 of the speaker unit 1 serves as a back cavity.

According to the first aspect of the invention, in such a system, a ventilation hole 7 is provided between the back cavity 6 on the back surface of the speaker unit 1 and the vehicle interior 5.

According to a second aspect of the present invention, the ventilation hole 7 is formed in the speaker unit 1 itself or in the vicinity of the speaker unit 1, and is configured to function as a high-pass filter in an acoustic low frequency range. Is. Further, the invention of claim 3 has a structure in which the vent hole 7 can adjust the opening area.

[0011]

[Action]

 Since the back cavity 6 on the back surface of the speaker unit 1 and the vehicle interior 5 are communicated with each other by the ventilation hole 7 as in claim 1, when the door of the vehicle interior is opened and closed, the vehicle interior 5 and the back cavity 5 are opened. Since air will pass between the vehicle interior 6 and the back cavity 6, the pressure difference between the vehicle interior 5 and the back cavity 6 can be prevented from becoming abnormally large.

As a result, it is possible to prevent an abnormal force from acting on the vibration system such as the diaphragm of the speaker unit 1, and it is possible to reliably prevent damage to the vibration system and deterioration of the speaker characteristics.

According to a second aspect of the present invention, the ventilation hole 7 is formed in the speaker unit 1 itself or in the vicinity of the speaker unit 1 and functions as a high-pass filter in an acoustic low frequency range. With this configuration, it is possible to suppress an abnormal increase in the low frequency range due to the baffle effect in the vehicle compartment, to obtain a flat reproduced sound pressure frequency characteristic in the low frequency range, and to improve the acoustic characteristics.

According to a third aspect of the present invention, the opening area of the ventilation hole 7 can be adjusted, so that the opening area of the ventilation hole 7 can be adjusted when the speaker unit is mounted on a vehicle or after the mounting. Thus, the acoustic characteristic in the low frequency range can be freely selected.

[0015]

【Example】

 Next, how the in-vehicle speaker system according to the present invention is actually embodied will be described by way of examples. The vent hole of the present invention can be opened at a position away from the speaker unit in order to prevent a sudden pressure change when opening and closing a door or the like. However, in order to guide the sound of the back cavity into the passenger compartment, suppress the baffle effect in the passenger compartment, prevent abnormal rise in the low frequency range, and improve the acoustics, the ventilation hole is used as a speaker unit. It is better to open it near the diaphragm.

FIG. 2 is a plan view showing an example in which a ventilation hole according to the present invention is formed by using a mounting portion of a speaker unit, and FIG. 3 is a sectional view taken along line III-III in FIG. Reference numeral 8 is a metal frame connected to the body of the automobile, on which the rear tray 2 is fixed. The illustrated speaker unit 1 is a cone type, and a cone 11 is supported inside a frame 10 fixed to a yoke 9.

That is, the outer circumference of the cone 11 is laminated and fixed to the flange portion 13 on the outer circumference of the frame 10 via the damper 12. A center cap 14 is attached to the center of the cone 11, and a coil 16 is wound around a coil bobbin 15 connected to the outer peripheral position of the center cap 14.

To mount the speaker unit 1, the screws 17 are inserted into the through holes formed in the flange portion 13 of the frame 10 and the rear tray 2 and are screwed into the nuts 18 on the back surface, so that the speaker The outer peripheral portion of the unit 1 is fixed to the rear tray 2. Further, the metal body-side frame 8 is formed with a trapezoidal portion 8b having a shape conforming to the back surface shape of the speaker unit 1, and a fixing plate fixed on the yoke 9 is fixed to the backing plate 19 overlaid thereon. The bolt 20 is inserted, and the nut 21 is tightened and fixed.

In the case of the present invention, the flange portion 13 of the frame 10 of the speaker unit 1 is provided with a slit 22 concentric with the flange portion 13. Further, as shown in FIG. 4, the rear tray 2 has a cutout portion 24 except for the region of the screw insertion hole 23. Therefore, in the state where the speaker unit 1 is attached as shown by the chain line, the slit 22 is formed. Through this, the trunk room and the passenger compartment will communicate with each other, allowing air to flow. Note that, as shown in FIG. 3, a slit 2s may be formed on the rear tray 2 side so as to overlap the slit 22 of the flange portion 13.

By providing the slits for ventilation in this way, the pressure when opening and closing the door and the luggage compartment passes through the slits 22, so it is possible to prevent the pressure difference from becoming abnormally high, and to prevent shocking. It is possible to prevent damage to the cone 11 and the like due to pressure and deterioration of the speaker characteristics due to repeated pressure differences. Further, since a part of the sound generated on the trunk room side is guided into the passenger compartment through the slit 22, abnormal sound in the low frequency range can be prevented.

A ring-shaped spacer 27 may be sandwiched between the illustrated rear tray 2 and the flange portion 13. As shown in FIG. 5, an arcuate screw insertion slit 25 and a slit 26 for a ventilation hole are alternately opened in the spacer 27, and the spacer 27 is inserted into the flange of the rear tray 2 and the speaker unit 1 of FIG. Insert the mounting screw 17 in the order of the screw insertion hole of the flange portion 13 → the screw insertion slit 25 of the spacer 27 → the screw insertion hole 23 of the rear tray 2 and screw it into the nut 18. ..

At this time, by rotating the spacer 27 with the screw 17 loosened and adjusting the overlapping amount of the slit 26 for ventilation of the spacer 27 and the slit 22 of the flange portion 13, the opening area of the ventilation hole is adjusted. Can be adjusted. This adjustment may be performed when the speaker unit 1 is mounted, but may be adjusted by the end user as desired. The width of the slit 26 may be gradually narrowed as shown by the chain line.

FIG. 6 is a plan view and a bb cross-sectional view showing another embodiment in which a spacer 27 is used to form a vent hole. The vent hole 28 is perpendicular to the screw insertion hole 29. That is, it is opened in the radiation direction. Therefore, if the spacer 27 is fixed by sandwiching it between the flange portion 13 and the rear tray 2 in FIG. 3, when the door is opened or closed, the high pressure side air passes in the direction perpendicular to the screw 17 and the pressure difference is generated. descend. As described above, when the vent hole 28 formed in the spacer 27 in the radial direction is used, it is not necessary to form the slit 22 of the flange portion 13 as shown in FIG.

FIG. 7 is a cross-sectional view in the case where the speaker grill 31 is provided, and the speaker grill 31 can be provided with a ventilation hole 34 in the same direction as the mounting screws 32, 33 or a ventilation hole 35 in the radial direction.

As described above, in addition to the case where the ventilation hole is opened using the speaker unit 1 itself or the mounting portion thereof, as shown by the broken line in FIG. 3, in the region where the body side frame 8 does not exist, only the rear tray 2 is passed. The pores 30 can also be opened. Normally, the rear tray 2 is covered with a cloth for interior, so that the ventilation holes 30 do not deteriorate the design.

As the shape of the ventilation hole, a slit shape is illustrated, but other shapes than the slit shape may be used. In addition, the shape and dimensions of each ventilation hole are determined according to the set frequency of the acoustic high-pass filter that suppresses the low frequency range.

In the above-mentioned embodiment, the rear speaker is attached to the rear tray, but the same applies to the case of the door speaker, in which case the speaker unit itself or its attachment portion is provided between the back cavity and the vehicle compartment. The ventilation hole can be formed by using the support member of the speaker unit or the like.

[0028]

[Effect of the device]

 Since the back cavity 6 on the back surface of the speaker unit 1 and the vehicle compartment 5 communicate with each other through the ventilation hole 7 as described in claim 1, when the door or the trunk room is opened or closed, the vehicle interior 5 and the back cavity are opened. It is possible to prevent damage to the vibration system of the speaker unit 1 or deterioration of the characteristics thereof due to an excessive pressure difference between the speaker unit 6 and the pressure unit 6.

Further, as in claim 2, the ventilation hole 7 is formed in the speaker unit 1 itself or in the vicinity of the speaker unit 1, and also functions as a high-pass filter in an acoustic low frequency range. With this configuration, it is possible to suppress an excessive baffle effect and obtain a flat reproduced sound pressure frequency characteristic in the low frequency range.

Moreover, as described in claim 3, by making the opening area of the ventilation hole 7 adjustable, the opening area of the ventilation hole 7 can be adjusted when the speaker unit is mounted on a vehicle or after mounting. By adjusting, the high pass filter characteristic in the low frequency range can be freely selected.

[Brief description of drawings]

FIG. 1 is a sectional view illustrating the basic principle of an in-vehicle speaker system according to the present invention.

FIG. 2 is a plan view showing an embodiment of the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a plan view showing a state in which a flange portion of a speaker unit and a rear tray overlap each other.

FIG. 5 is a plan view showing an example of a spacer.

6A and 6B are a plan view and a cross-sectional view illustrating another vent hole using a spacer.

FIG. 7 is a cross-sectional view showing an example of opening a ventilation hole using a speaker grill.

FIG. 8 is a perspective view showing a mounted state of a conventional speaker unit.

[Explanation of symbols]

 1 Speaker unit (rear speaker) 2 Rear tray 3 Trunk lid 4 Rear glass 5 Vehicle interior 6 Back cavity 7 Vent hole 8 Body side frame 8b Trapezoidal part 9 Yoke 10 Speaker unit frame 11 Cone 12 Damper 13 Speaker unit flange 14 Center Cap 15 Coil bobbin 16 Coil 17 Screw 19 Fixing plate 20 Fixing bolt 22 Slit 23 Screw insertion hole 24 Notch 25 Screw insertion slit 26 Vent slit 27 Spacer 28 Vent hole 29 Screw insertion hole 30 Vent hole in rear tray 31 Speaker grill 34,35 Vent

Claims (3)

[Scope of utility model registration request] 1. A system in which a back cavity is provided on the back surface of a speaker unit mounted on an automobile, wherein a vent hole 7 is provided between a back cavity 6 on the back surface of the speaker unit 1 and a vehicle compartment 5. Characteristic vehicle speaker system. 2. The speaker unit 1 having the vent hole 7
The vehicle-mounted speaker system according to claim 1, wherein the speaker system is formed on itself or in the vicinity of the speaker unit 1 and is configured to function as a high-pass filter in an acoustic low frequency range. 3. The vent hole 7 has an opening area that can be adjusted.
The in-vehicle speaker system described.