Inductor devices – With outer casing or housing – Internal inductor support
Reexamination Certificate
1999-12-03
2001-07-31
Easthom, Karl D. (Department: 2832)
Inductor devices
With outer casing or housing
Internal inductor support
C336S090000, C336S174000, C336S175000, C336S176000
Reexamination Certificate
active
06268787
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a ferrite-core housing case for housing a ferrite core which is to be attached to a flat cable to suppress noises propagating through the flat cable, an anti-noise component in which a ferrite core is housed in such a case, and a wire harness and an electronic apparatus to which such an anti-noise component is attached.
2. Discussion of the Background
Conventionally, an anti noise measure is taken by using a ferrite core in a cable connecting various electronic apparatuses. Such a cable includes a flat cable. Also in a cable of this kind, an anti noise measure is taken in the same manner.
As a ferrite core used for an anti noise measure in a flat cable, used is a flat O-like (flat ring-like) ferrite core
1
such as shown in FIG.
6
and having a slit-like hole
2
through which a flat cable FC is to be passed. Such a ferrite core
1
has the illustrated integral type structure or a split type one in which split core halves are butted against each other to form a flat O-like shape.
This ferrite core
1
is used while the flat cable FC is passed therethrough. When the cable is passed and no further measure is taken, the ferrite core is moved along the cable. When the ferrite core
1
is moved on the flat cable FC, there arises a fear that the ferrite core
1
collides with the interior of an apparatus in the vicinity of the place where the ferrite core
1
is attached, and the apparatus or the ferrite core
1
is damaged. Furthermore, a desired noise reduction effect may not be attained depending on the place of the flat cable FC.
These problems can be solved by fixing the ferrite core on the flat cable. This can be implemented by a method in which the ferrite core is fixed to the flat cable by means of an adhesive agent or an adhesive tape, or that in which the ferrite core is fixed to an apparatus housing or a circuit board which is in the vicinity of the core, by means of an adhesive agent or an adhesive tape.
However, these methods are low in working efficiency. As a countermeasure, a component
5
such as shown in FIG.
7
and for fixing positions of a ferrite core and a flat cable has been proposed (produced by TOKIN Corporation, product name: FPD-CL-1 camp). The component
5
is characterized in that it is attached to a side face of each of the end portions of a ferrite core
1
and can be fixed to an apparatus housing or a circuit board
10
by, for example, fastening of a bolt
7
and a nut
8
with using a hole
6
formed in the component
5
.
In the case where the ferrite core
1
is to be attached to an apparatus housing or a circuit board by using the component
5
of
FIG. 7
, however, the component is attached to the ferrite core
1
and the fixing work must be then conducted while pressing the ferrite core
1
and the component
5
by a hand so as not to separate them from each other. When the ferrite core
1
is once fixed onto the circuit board and the core is to be then detached therefrom, the ferrite core
1
can be detached from the circuit board, only after the whole of the assembly is detached therefrom.
In order to solve these problems, the assignee of the present application has proposed an anti-noise component for a flat cable in U.S. patent application Ser. No. 09/261,228. The proposed anti-noise component is characterized in that a split type ferrite core
1
(configured by butting split ferrite core halves
1
a
and
1
b
against each other) which is to be attached to a flat cable FC is housed in an openable and closeable case
15
(configured by coupling split case halves
15
a
and
15
b
to each other), and a coupling portion
18
for fixation to a circuit board is formed on a bottom portion of the case, whereby attachment and detachment of the ferrite core
1
is facilitated, and the ferrite core
1
is prevented from being damaged with a shock, and easily attached to an apparatus, a circuit board, etc.
In the anti-noise component shown in
FIG. 8
, the ferrite core
1
is pressed by a spring portion
16
formed in a center portion of the upper face of the split case half
15
b
in order to, when the case
15
is closed, prevent the ferrite core
1
housed therein from being moved in the case. When the ferrite core
1
is moved in the case
15
, the ferrite core
1
bumps against the case
5
to produces acoustic noises. This is not preferable.
In the component disclosed in U.S. patent application Ser. No. 09/261,228, as shown in
FIG. 8
, the spring portion
16
is disposed in the center portion of the upper face of the split case half. Because the split case halves
15
a
and
15
b
have a flexibility of a certain degree, the disposition of the spring portion at such a position causes the force of the spring portion
16
pressing the ferrite core
1
to be applied also to the case
15
, thereby raising the split case half
15
b
. This raised state is shown in FIG.
9
. When the ferrite core
1
is housed, the upper face of the split case half
15
b
which is originally in the state indicated by the solid line is raised in the center portion of the case half to warp the case
15
. When the case
15
is warped, the force of the spring portion
16
pressing the ferrite core
1
is reduced, so that the ferrite core
1
cannot be sufficiently fixed. The warped state of the case
15
impairs the appearance of the case.
Also in the case where two spring portions
17
are disposed in a center portion of the upper face of the split case half
15
b
as shown in
FIG. 10
, there arises a phenomenon in which, when the ferrite core
1
is housed, the center portion of the case half is raised as indicated by the broken lines to warp the case
15
.
The force of the spring portion is enhanced by increasing the inclination angle of the spring portion with respect to the inner face of the case. In accordance with enhancement of the force, also the force of raising the split case half is increased so as to further warp the case.
SUMMARY OF THE INVENTION
It is a first object of the invention to provide a ferrite-core housing case which has been proposed by the assignee of the present application, and in which warpage of the case housing a ferrite core that is prevented from occurring, the ferrite core can be pressed so as to be surely held, and fixation and detachment of the ferrite core with respect to a flat cable can be easily implemented, and also an anti-noise component in which a ferrite core is housed in such a case.
It is a second object of the invention to provide a wire harness and an electronic apparatus which have an anti-noise component that can be easily attached to and detached from a flat cable and that can surely hold an incorporated ferrite core.
In order to attain the objects, the ferrite-core housing case of the present invention comprises a first split case half, and a second split case half that is openable with respect to the first split case half, a ferrite core to be housed in the case, through which an electronic cable passes, a pair of spring portions which press the ferrite core are formed in at least one of the first and second split case halves, and a fulcrum of each of the spring portions is located on a side face of the split case half while an acting point is located on a center side.
According to the invention, the fulcrum of a spring portion which is disposed in a split case half is located on a side face of the split case half or in the vicinity of the side face, thereby preventing the split case half from being pushed upward to be warped.
When the anti-noise component for a flat cable is to be attached to a flat cable, the component has a flat shape in the same manner as the shape of the flat cable. The side faces of the split case half are coupled to each other. When the fulcrum of a spring portion is located in the vicinity of the center of the upper face of the split case half, therefore, a force is applied to the upper face of the split case half, so that, if the split case half is highly flexible, a center portion of the upper face of
Easthom Karl D.
Mai Anh
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
TDK Corporation
LandOfFree
Ferrite-core housing case anti-noise component wire harness... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ferrite-core housing case anti-noise component wire harness..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ferrite-core housing case anti-noise component wire harness... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2504556