Field of the Invention
[0001] The present invention relates to a chip inductor; and, more particularly, to a multilayer
type chip inductor employing a pair of outermost sheets having an identical terminal
pattern in shape, respectively, the terminal pattern being capable of providing various
positions for a via hole for electrically connecting the terminal pattern with conductor
patterns of intermediate sheets.
Background of the Invention
[0002] In general, a multilayer type chip inductor is comprised of a stack of sheets made
of a plurality of ferrite or dielectric materials, having respective coil patterned
conductors formed thereon and connected electrically by the via holes in series with
each other in substantially zigzag fashion. Such a multilayer type chip inductor is
used, for example, for suppressing noise or making a LC resonance circuit.
[0003] Fig. 1 shows an exploded view of the conventional multilayer type chip inductor disclosed
in Japanese Laid-open Utility Model Publication No. 57-100209.
[0004] As shown, the conventional multilayer type chip inductor includes a pair of generally
rectangular outermost sheets 1, 1' made of the ferrite or the dielectric material
and a plurality of intermediate sheets 2 made of the ferrite and dielectric material
stacked one above the other and firmly sandwiched between the outermost sheets 1,
1'.
[0005] The outermost sheet 1 has a front surface formed with a generally L-shaped electric
terminal pattern 6. The electric terminal pattern 6 has a lengthwise strip 6a extending
along and adjacent to a longer side of the outermost sheet 1 and terminating at a
generally intermediate portion of the longer side of the outermost sheet 1, and a
lateral strip 6b continued to the lengthwise strip 6a and extending along a shorter
side of the outermost sheet 1 for electric connection with an end cap or like terminal
member (not shown).
[0006] Similarly, the outermost sheet 1' has at its front surface a generally L-shaped electric
terminal pattern 6' composed of a lengthwise strip 6'a and a lateral strip 6'b, wherein,
the terminal pattern 6' thereof is offset 180° with respect to the terminal pattern
6 on the outermost sheet 1 about an imaginary plane passing intermediately between
the outermost sheets 1, 1' in a widthwise direction of the stack, and the lengthwise
strip 6'a has at its end a via hole 4'. The via hole 4' is formed by perforating the
outermost sheet 1' across the thickness thereof so as to leave a cylindrical wall
(not shown).
[0007] Each of the intermediate sheets 2 has a front and a reverse surfaces opposite to
each other. The front surface of each of the intermediate sheets 2 is, respectively,
formed with a generally U-shaped electric conductor pattern 3. Each of the conductor
patterns 3 has a perforated end 3a formed with a via hole 4 and a non-perforated end
3b. Similar to the above-mentioned via hole 4', the via hole 4 is formed by perforating
the respective intermediate sheet 2 across the thickness thereof so as to leave a
cylindrical wall (not shown). The above-mentioned cylindrical walls are plated with
the conductive material.
[0008] When assembling the sheets 1, 2 and 1' together to provide a substantially complete
multilayer type chip inductor, the intermediate sheets 2 are stacked one above the
other in such a way that, when one intermediate sheet 2 is turned 180° on an imaginary
plane parallel thereto, the perforated end 3a and the non-perforated end 3b thereof
are, respectively, contacted with the non-perforated end 3b and the perforated end
3a of the neighboring intermediate sheet 2 thereabove or therebelow, whereby the intermediate
sheets 2 can be electrically connected with each other through the via holes 4. With
respect to the outermost sheets 1, 1', the outermost sheet 1 is positioned below the
lowermost intermediate sheet 2 in such a way that the lengthwise strip 6a thereof
comes into contact with the perforated end 3a of the lowermost intermediate sheet
2 through the via hole 4, and the outermost sheet 1' is positioned above the uppermost
intermediate sheet 2 in such a way that the lengthwise strip 6'a thereof comes into
contact with the non-perforated end 3b of the uppermost intermediate sheet 2 through
the via hole 4' thereof, whereby the conductor patterns 3 on the intermediate sheets
2 and the terminal patterns 6, 6' on the outermost sheets 1, 1' are electrically connected
with each other through the via holes 4, 4'.
[0009] In such a multilayer type chip conductor, since the outermost sheets are, respectively,
formed with the terminal patterns requiring a different mask from each other, it results
in a higher production cost and complicated manufacturing processes. Furthermore,
when a different inductance is desired, the shape and/or the size of the conductor
pattern of the intermediate sheet must also change, which, in turn, requires the shape
and/or the size of the terminal pattern of the outermost sheets to be also changed
so as to electrically connect the terminal pattern with the changed conductor pattern
of the intermediate sheet, again necessitating a higher production cost and complicated
manufacturing processes.
Summary of the Invention
[0010] It is, therefore, a primary object of the present invention to provide a multilayer
type chip inductor which removes the need for forming different terminal patterns
on its outermost sheets, when a different inductance is required therefrom.
[0011] In accordance with one aspect of the present invention, there is provided a pair
of sheets having an identical terminal pattern, respectively, the terminal patterns
being identical in shape, one of the terminal patterns being formed with a via hole
filled with a conductive material for an electrical connection with the other thereof,
wherein the sheets are arranged in such a way that when one of the sheets are turned
180° on an imaginary plane parallel thereto the terminal patterns of the sheets are
allowed to be overlapped with each other, and the terminal patterns of the sheets
are allowed to be electrically connected with each other through the via hole.
[0012] In accordance with another aspect of the present invention, there is provided a pair
of outermost sheets having a terminal pattern, respectively, the terminal patterns
being identical in shape, one of the terminal patterns being formed with a via hole
filled with a conductive material, wherein the outermost sheets are arranged in such
a way that, when one of the outermost sheets is turned 180° on an imaginary plane
parallel thereto, the terminal patterns of the outermost sheets are allowed to be
overlapped with each other, and a t least one intermediate sheets interposed between
the outermost sheets and having a conductor pattern, respectively, the conductor patterns
being identical in shape, each of the conductor patterns being formed with a via hole
filled with a conductive material for an electrical connection with neighboring conductor
patterns, wherein the intermediate sheets are stacked one above the other and sandwiched
between the outermost sheets in such a way that, when one of the intermediate sheets
is turned 180° on the imaginary plane the conductor patterns thereof are allowed to
be overlapped with the conductor patterns of the neighboring intermediate sheets,
and the terminal patterns of the outermost sheets and the conductor patterns of the
intermediate sheets are allowed to be electrically connected with each other through
their via holes.
[0013] In accordance with further another aspect of the present invention, there is provided
a multilayer type chip inductor having at least one intermediate sheet formed with
a conductor pattern thereon, comprising a pair of outermost sheets having a terminal
pattern, respectively, wherein each of the terminal patterns includes a via hole for
electrically connecting the terminal pattern to the conductor pattern of the intermediate
sheet and is capable of providing various positions for the via hole so as to accommodate
various conductor patterns of the intermediate sheet.
Brief Description of the Drawings
[0014] The above and other objects and features of the present invention will become apparent
from the following description of the preferred embodiments given in conjunction with
the accompanying drawings, wherein:
Fig. 1 shows an exploded perspective view of the conventional multilayer type chip
inductor;
Fig. 2 illustrates an exploded perspective view of the multilayer type chip inductor
in accordance with a first preferred embodiment of the present invention;
Fig. 3 displays an exploded perspective view of the multilayer type chip inductor
in accordance with a second preferred embodiment of the present invention;
Fig. 4 provides an exploded perspective view of the multilayer type chip inductor
employing an outermost sheet having a different terminal pattern in shape from that
of the outermost sheet in Fig. 3;
Fig. 5 depicts an exploded perspective view illustrating a modified form of the chip
inductor shown in Fig. 3; and
Fig. 6 presents an exploded perspective view setting forth a modified form of the
chip inductor shown in Fig. 4.
Detailed Description of the Preferred Embodiments
[0015] There are provided in Figs. 2 to 6 a exploded perspective view of a multilayer type
chip inductor in accordance with the present invention, respectively.
[0016] Referring to Fig. 2, a multilayer type chip inductor in accordance with a first preferred
embodiment of the present invention includes a pair of sheets 10, 10' made of a ferrite
and a dielectric material. Each of the sheets 10, 10' has a rectangular shape and
a terminal pattern 12 having a substantially "T" shape thereon. Each of the terminal
patterns 12 has a lateral strip 12a extending along a shorter side of the sheet 10
or 10', and a lengthwise strip 12b extending from a substantially intermediate portion
of the length of the lateral strips 12a, along a longer side of the sheet 10 or 10',
and terminating at a generally intermediate portion of the length of the sheet 10
or 10'. The sheet 10' has at its the lengthwise strip 12b a via hole 14 filled with
a conductive material for an electrical connection with the sheet 10.
[0017] The sheets 10, 10' are assembled in such a way that, when one of the sheets 10, 10'
are turned 180° on an imaginary plane parallel thereto, the terminal patterns 12 of
the sheets 10, 10' are overlapped with each other. This allows the terminal patterns
12 of the sheets 10, 10' to be electrically connected with each other through the
via hole 14.
[0018] Referring to Fig. 3, a multilayer type chip inductor in accordance with a second
preferred embodiment of the present invention includes a pair of outermost sheets
20, 20' made of the ferrite and the dielectric material, and at least one intermediate
sheets 30 made of the ferrite and the dielectric material and interposed between the
outermost sheets 20, 20'.
[0019] Each of the outermost sheets 20, 20' has a rectangular shape and a terminal pattern
22 having a substantially "T" shape thereon. Similar to the terminal pattern 12 accordance
with a first preferred embodiment of the present invention, the terminal pattern 22
of each of the outermost sheets 20, 20' has a lateral strip 22a and a lengthwise strip
22b. The outermost sheet 20' has at its the lengthwise strip 22b a via hole 24 filled
with a conductive material for an electrical connection with the intermediate sheet
30 therebelow, as will be described in later.
[0020] The intermediate sheets 30 have a conductor pattern 32, respectively. The conductor
patterns 32 are identical in shape, for example, ⊏-shape, respectively. The conductor
pattern 32 of each of the intermediate sheets 30 has a perforated end 32a formed with
a via hole 34 and a non-perforated end 32b. The via hole 34 is formed by perforating
the respective intermediate sheet 30 across the thickness thereof and filled with
a conductive material for an electrical connection with neighboring patterns, for
example, the terminal pattern of the outermost sheet thereabove and the conductor
pattern of the intermediate sheet therebelow, or the conductor patterns of the intermediate
sheets thereabove and therebelow.
[0021] The outermost sheets 20, 20' are arranged in such a way that, when one of the outermost
sheets 20, 20' is turned 180° on an imaginary plane parallel thereto, the terminal
patterns 22 thereof are allowed to be overlapped with each other; and the intermediate
sheets 30 are stacked one above the other and sandwiched between the outermost sheets
20, 20' in such a way that, when one of the intermediate sheets 30 is turned 180°
on the imaginary plane, the conductor pattern 32 thereof is allowed to be overlapped
with the conductor patterns of the neighboring intermediate sheets 30. To be more
specific, when assembling the sheets 20, 20' and 30 together to provide a substantially
complete multilayer type chip inductor, the intermediate sheets 30 are stacked in
such a way that their perforated ends 32a and the non-perforated ends 32b are, respectively,
contacted with the non-perforated ends 32b and the perforated ends 32a of the neighboring
intermediate sheets 30 through the via holes 34. This allows the conductive patterns
32 of the intermediate sheets 30 to be electrically connected with each other. With
respect to the outermost sheets 20, 20', the outermost sheet 20 is positioned below
the lowermost intermediate sheet 30 in such a way that the lengthwise strip 22b thereof
comes into contact with the perforated end 32a of the lowermost intermediate sheet
30 through the via hole 34 of the lowermost intermediate sheet 30, and the outermost
sheet 20' is positioned above the uppermost intermediate sheet 30 in such a way that
the lengthwise strip 22b thereof comes into contact with the non-perforated end 32b
of the uppermost intermediate sheet 30 through the via hole 24 thereof. This allows
the terminal patterns 22 on the outermost sheets 20, 20' and the conductor patterns
32 on the intermediate sheets 30 to be electrically connected with each other through
the via holes 24, 34.
[0022] Although the above discussions were presented referring to a situation where the
terminal pattern of the outermost sheet has the substantially "T" shape and the conductor
pattern of the intermediate sheet has a ⊏-shape, their shapes and/or sizes can be
changed depending on the desired inductance. For example, as shown in Fig. 4, the
terminal patterns 22 of the outermost sheets 20, 20' may have a rectangular shape.
[0023] When a different inductance is required, the conductor pattern of the intermediate
sheet must also change in the shape and/or the size. Unlike the prior art multilayer
type chip inductor, the inventive multilayer type chip inductor can easily accommodate
such a change. For example, as shown in Figs. 5 and 6, when the conductor pattern
32 of the intermediate sheet 30 increases in size in order to obtain an increased
inductance, the location of the via hole 24 of the terminal pattern 22 can be changed
suitably in such a way that the terminal pattern 22 of the outermost sheet 20' is
electrically connected with the changed conductor pattern in the inventive multilayer
type chip inductor. In other word, in the inventive multilayer type chip inductor,
the terminal pattern of the outermost sheet can be electrically connected to various
conductor patterns of an intermediate sheet by simply changing the position of the
via hole, eliminating the need to change the shape and/or the size of the terminal
pattern of the outermost sheet. Furthermore, in the inventive multilayer type chip
inductor, since the outermost sheets include an identical terminal pattern in shape,
respectively, it is possible to reduce a production cost and to facilitate manufacturing
processes thereof.
[0024] While the present invention has been described with respect to certain preferred
embodiments only, other modifications and variations may be made without departing
from the scope of the present invention as set forth in the following claims.
1. A multilayer type chip inductor comprising :
a pair of sheets having an identical terminal pattern, respectively, the terminal
patterns being identical in shape, one of the terminal patterns being formed with
a via hole filled with a conductive material for an electrical connection with the
other thereof, wherein the sheets are arranged in such a way that when one of the
sheets are turned 180° on an imaginary plane parallel thereto the terminal patterns
of the sheets are allowed to be overlapped with each other, and the terminal patterns
of the sheets are allowed to be electrically connected with each other through the
via hole.
2. The multilayer type chip inductor of claim 1, wherein each of the sheets has a rectangular
shape and the terminal pattern thereof has a lateral strip extending along a shorter
side of the sheet, and a lengthwise strip extending from an intermediate portion of
the lateral strip, along a longer side of the sheet and terminating at a generally
intermediate portion of the longer side of the sheet.
3. The multilayer type chip inductor comprising :
a pair of outermost sheets having a terminal pattern, respectively, the terminal patterns
being identical in shape, one of the terminal patterns being formed with a via hole
filled with a conductive material, wherein the outermost sheets are arranged in such
a way that, when one of the outermost sheets is turned 180° on an imaginary plane
parallel thereto, the terminal patterns of the outermost sheets are allowed to be
overlapped with each other; and
at least one intermediate sheets interposed between the outermost sheets and having
a conductor pattern, respectively, the conductor patterns being identical in shape,
each of the conductor patterns being formed with a via hole filled with a conductive
material for an electrical connection with neighboring conductor patterns, wherein
the intermediate sheets are stacked one above the other and sandwiched between the
outermost sheets in such a way that, when one of the intermediate sheets is turned
180° on the imaginary plane the conductor patterns thereof are allowed to be overlapped
with the conductor patterns of the neighboring intermediate sheets, and the terminal
patterns of the outermost sheets and the conductor patterns of the intermediate sheets
are allowed to be electrically connected with each other through their via holes.
4. The multilayer type chip inductor of claim 3, wherein each of the outermost sheets
has a rectangular shape and the terminal pattern thereof has a lateral strip extending
along a shorter side of the sheet, and a lengthwise strip extending from an intermediate
portion of the lateral strip, along a longer side of the outermost sheet and terminating
at a generally intermediate portion of the longer side of the outermost sheet.
5. The multilayer type chip inductor of claim 3, wherein the terminal pattern of each
of the outermost sheets has a substantially "T" shape.
6. The multilayer type chip inductor of claim 3, wherein the terminal pattern of each
of the outermost sheets has a rectangular shape.
7. The multilayer type chip inductor of claim 3, wherein the conductor pattern of the
intermediate sheet has a ⊏-shape.
8. A multilayer type chip inductor having at least one intermediate sheet formed with
a conductor pattern thereon, comprising:
a pair of outermost sheets having a terminal pattern, respectively, wherein each of
the terminal patterns includes a via hole for electrically connecting the terminal
pattern to the conductor pattern of the intermediate sheet and is capable of providing
various positions for the via hole so as to accommodate various conductor patterns
of the intermediate sheet.
9. The multilayer type chip inductor of claim 8, wherein each of the outermost sheets
has a rectangular shape and each of the terminal patterns has a lateral strip extending
along a shorter side of the outermost sheet, and a lengthwise strip extending from
an intermediate portion of the lateral strip, along a longer side of the sheet and
terminating at a generally intermediate portion of the longer side of the sheet.
10. The multilayer type chip inductor of claim 9, wherein the terminal pattern has a substantially
"T" shape.
11. The multilayer type chip inductor of claim 8, wherein each of the terminal pattern
of the outermost sheets has a rectangular shape.