Electrical audio signal processing systems and devices – Electro-acoustic audio transducer – Electromagnetic
Reexamination Certificate
2002-09-17
2004-10-26
Kuntz, Curtis (Department: 2643)
Electrical audio signal processing systems and devices
Electro-acoustic audio transducer
Electromagnetic
C381S389000, C381S395000, C181S149000
Reexamination Certificate
active
06810129
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a speaker for automobile use of a waterproof structure which is assembled into an inside of a door of an automobile.
BACKGROUND ART
Generally, since this kind of speaker for automobile use is assembled into a position below a window glass inside a door of an automobile, waterproofing measure comes to be taken to prevent the rain water or car-washing water or the like, from getting into important vibration elements of the speaker along the window glass. Concrete examples thereof will be given hereafter.
FIG. 1
is a schematic cross sectional view to show a conventional ordinary automobile-mounted speaker, and
FIG. 2
is an external view of FIG.
1
. In the figures, reference numeral
1
denotes a frame of the automobile-mounted speaker. This frame
1
is formed into a trumpet shape having a plurality of openings
2
1
-
2
4
. Reference numeral
3
denotes an outward-looking front-end flange which is integrally formed around a peripheral edge of a front-end opening. Reference numeral
4
denotes an annular wall portion bent from the rear end of the trumpet-shape part of the frame
1
in a diametrically inner direction so as to be positioned near the rear portion of the openings
2
1
-
2
4
. This annular wall portion
4
serves as an area for adhering a damper thereto, which will be described later. Reference numeral
5
denotes a rear-end stepped portion which is bent from the inner peripheral edge portion of the annular wall portion
4
in an axially outward direction. At the rear-end peripheral portion of this rear-end annular stepped portion
5
, there is formed an annular rear wall portion
6
which is bent in the diametrically inward direction.
Reference numeral
7
denotes a cone paper (vibrating diaphragm) whose peripheral edge portion is adhered to the front-end opening edge portion of the frame
1
. Reference numeral
8
denotes the damper whose peripheral edge portion is adhered to a front face of the annular wall portion
4
. The cone paper
7
and the damper
8
are integrally connected to a bobbin
9
at the respective central portions.
Reference numeral
10
denotes a magnetic circuit unit which is mounted on the rear wall portion
6
of the frame
1
. This magnetic circuit unit
10
is to resonate the damper
8
and the cone paper
7
through the bobbin
9
, and is made up of a ring-shaped magnet
11
, first and second magnetic members
12
,
13
which sandwich the magnet
11
, and a voice coil
14
. At this point the first magnetic member
12
is formed into a projected shape in cross section having a central axial portion
12
a
which is coaxial with the bobbin
9
. The second magnetic member
13
is made of a ring plate which is fitted into the central axial portion
12
a
of the first magnetic member
12
. The voice coil
14
is interposed between the central axial portion
12
a
and the second magnetic member
13
. The voice coil
14
is arranged to be energized.
The speaker for automobile use having the above described arrangement is set in position by assembling the front-end flange
3
of the frame
1
to a metal plate below the window glass inside the door of the automobile. In order to cover the metal plate, an interior decorating plate is attached to the door, and an opening for the speaker in the interior decorating plate and the speaker having adhered thereto a gasket
15
are set in position close to each other.
Next, a description will now be made about the operation.
The sound is generated by a vibration of the cone paper
7
and the damper
8
through the bobbin
9
by means of audio current at the time of energization of the voice coil
14
.
Since the conventional ordinary speaker for automobile use has the above described arrangement, there was a problem that the rain water or car-washing water which enters the inside of the door through the window glass of the door at the time of rainy weather or at the time of car washing, splashes onto the speaker thereby resulting in a deterioration of the speaker characteristics or performance.
In other words, the rain water or car-washing water is likely to enter from the openings
2
1
-
2
4
which are opened at the trumpet-shape part of the frame
1
(especially from the upper and left and right openings
2
1
-
2
3
) so as to be positioned below the window glass of the automobile door. Due to water impregnation by the entered water into the water-absorbing cone paper
7
and the damper
8
, there were problems that the resonance characteristics of the cone paper
7
and the damper
8
get deteriorated, that the amount of water impregnation gradually increases and the penetrated water finds its way into the magnetic circuit unit
10
to thereby generate abnormal noises, and that rust is formed inside the magnetic circuit unit
10
.
In order to solve the above described problems, there has been proposed a speaker for automobile use with a waterproof cover.
FIG. 3
is a perspective view to show a conventional speaker for automobile use with a waterproof cover. The same reference numerals have been given to the same constituent parts as those in
FIGS. 1 and 2
and further descriptions on them have been omitted. In
FIG. 3
, reference numeral
16
denotes the waterproof cover mounted on a rear side of the frame
1
. This waterproof cover
16
covers the upper, left and right openings
2
1
-
2
3
which are formed in the trumpet-shape part of the frame
1
as shown in
FIGS. 1 and 2
, and also covers the magnetic circuit unit
10
in the rear portion.
By means of covering the rear side of the frame
1
with the waterproof cover
16
as described above, the rain water or the car-washing water that has entered the inside of the door along the window glass is prevented from splashing onto the essential vibrating elements of the speaker or from penetrating into the magnetic circuit unit
10
through the openings
2
1
-
2
3
.
Since the conventional speaker for automobile use with the waterproof cover has the above described arrangement, there was a problem that the waterproof cover
16
which covered from the front-end flange
3
of the frame
1
to the rear end of the magnetic circuit unit
10
itself became large in size, thereby resulting in an increase of cost. Further, since the large-sized waterproof cover
16
becomes occupying larger area for the assembled speaker, there was a problem that the place for assembled speaker to be attached was limited.
As another example of conventional speaker with the waterproof cover, Laid Open Japanese Utility Model No. 42286/1995 discloses a speaker for automobile use with waterproof structure which does not require the waterproof cover portion of a separate constituent part. In this automobile-mounted speaker, a partial waterproof cover which shields a space between the upper opening of the frame and the upper edge portion of the damper by means of bending forward, is integrally formed on a substantially semicircular edge portion on the upper side of the damper-mounting wall portion of the frame which is formed into a trumpet-shape having a plurality of openings.
In this conventional example, however, substantially the entire surface of the damper-mounting wall portion of the frame serves as the damper adhering area. Since the upper edge portion of the damper which is adhered to the damper-mounting wall portion is positioned closely to the waterproof cover portion, the water splashing from the upper opening onto the waterproof cover portion or the water entering from the upper opening by splashing at the magnetic circuit unit, get included into the damper by rolling over the waterproof cover portion. As a result, a problem arises that there is a higher possibility of the speaker characteristics' getting deteriorated by the wetting of the damper. Further, the waterproof cover portion is integrally formed only on the upper edge portion of the damper-mounting wall portion. Therefore, the orientation which the speaker can be mounted is restricted, and it requires an accuracy to mount the speaker. Therefore, there is a prob
Ensey Brian
Kuntz Curtis
Mitsubishi Denki & Kabushiki Kaisha
LandOfFree
Waterproof speaker for use in an automobile does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Waterproof speaker for use in an automobile, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Waterproof speaker for use in an automobile will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3308740