CA1050162A - Thin-film head with overlapping legs - Google Patents
Thin-film head with overlapping legsInfo
- Publication number
- CA1050162A CA1050162A CA218,340A CA218340A CA1050162A CA 1050162 A CA1050162 A CA 1050162A CA 218340 A CA218340 A CA 218340A CA 1050162 A CA1050162 A CA 1050162A
- Authority
- CA
- Canada
- Prior art keywords
- core part
- gap
- core
- loop
- shaped
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/265—Structure or manufacture of a head with more than one gap for erasing, recording or reproducing on the same track
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/31—Structure or manufacture of heads, e.g. inductive using thin films
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Magnetic Heads (AREA)
Abstract
ABSTRACT:
A thin-film magnetic head having improved playback properties in which the gap-bounding core parts overlap each other laterally while enclosing a layer having a gap and in which a first core part has the shape of a closed loop and is bridged in the centre by a second core part. The parts of the first core part on either side of the bridge are provided with identical coils, while the first core part at the area of the overlap is divided centrally by an extra gap. Upon playing back, the difference signals of the coils then provides an indication as regards the position relative to the track.
A thin-film magnetic head having improved playback properties in which the gap-bounding core parts overlap each other laterally while enclosing a layer having a gap and in which a first core part has the shape of a closed loop and is bridged in the centre by a second core part. The parts of the first core part on either side of the bridge are provided with identical coils, while the first core part at the area of the overlap is divided centrally by an extra gap. Upon playing back, the difference signals of the coils then provides an indication as regards the position relative to the track.
Description
~0S016Z
. ~
Thin-film ma~netic head.
The invention relates to a thin-film magnetic head which has an electric winding and comprises a number of core parts of a magnetisable material of which at least the gap-bounding core parts are thin layers and overlap each other laterally while enclosing a gap-defining~layer of a non-magnetisable material.
Such a magnetic head which is used for example in sboring in~ormation in magnetic disc memories, is 10 ~ known from the published German Patent Application
. ~
Thin-film ma~netic head.
The invention relates to a thin-film magnetic head which has an electric winding and comprises a number of core parts of a magnetisable material of which at least the gap-bounding core parts are thin layers and overlap each other laterally while enclosing a gap-defining~layer of a non-magnetisable material.
Such a magnetic head which is used for example in sboring in~ormation in magnetic disc memories, is 10 ~ known from the published German Patent Application
2,104,445.
Presently there exists in the industry a need of àn increase of memory storage capacity and hence . : :
o~ magnetic heads for very narrow tracks. The present track width lies in the range of 150 to 200 microns.
; In connection with the above, however, there exists a need of track widths of a few tens of microns. Since, however, magnetic heads suitable for such narrow tracks can no longer be realized in the conventional manner, in which two core parts are placed in line with the interposition o~ a non-magnetisable spacing member and in which the thickness of the core parts determines the track width, the thin-film magnetic head described in the above-mentioned German Patent Application has been proposed. In this mag-netic head, two core parts overlap each other laterally at the area o~ the gap as a result of which the gap wi~th ~-' - ~.
`~ i ) 10~0~6Z
is not determined by the thickness of the core parts but by the extent to which the core parts overlap each other. Such a construction enables the manufacture by means of thin-film methods and photolithographic methods of heads which are suitable for track widths of a few tens of microns. A
drawback is~ however, that the area over which the core parts overlap each other at the site of the gap, which area is large as compared with the thick-ness of the core partsJ adversely influences the playback properties of ~he head: the larger the extent of overlap, the smaller the playback efficiency.
It is the object of the lnvention to provide a head of the above-mentioned kind in which the playback proper~ies are less dependent on the extent of overlap of the core parts than in the known head and which more-over has a number of extra advantages.
For that purpose, according to a broad aspect of the present in-vention, there is provided a thin-film magnetic head comprising a first loop shaped core part of magnetizable material having an upper surface with an outer edge, a second core part of magnetizable material having a lower sur-face and an outer edge and extending from one s.ide of the upper surfaces of the first core part across the upper surface of the first core part to an opposite side of the first core part and overlapping an area of the upper surface of said opposite side of said first core part with a lower surface of said second core part, said second core part being magnetically coupled to said first core part at said one side of said first core part and provid-ing an elongated surface parallel with the upper surface of the first core part and having an elongated outer edge on said elongated surface parallel to said outer edge of said first core part, and a layer of non-magne~izable mater;al between the first and second core parts in the overlapping area thereof, the outer edges of said first and said second core parts forming therebetween a gap elongated in a direction perpendicular to the direction in which the second core part exte~ds across the first core part.
~ith the same overlap area of the gap-bounding , ~5 '' - .
~L~15011 6Z
parts, the magnetic head according to the invention has considerably better playback properties than the known head.
- If` desired, restriction of the overlap is possible by reducing the width of the second core part at the area of and on either side of the first core part.
The width of the second core part, at least at the area of the first core part, preferably is at most half of the width of the first core part.
Although the magnetic coupling of the above-mentioned ends of the core parts may be carried out, for example, by means of a closing yoke on which also an electric winding may be provided, a preferred embodiment of the magnetic head according to the invention is characterized in that the second core part is in the form of a closed loop and that the first core part bridges the loop at least substantially in the centre. Such a con-struction can be realized very suitably and in few steps by means of thin-~ilm methods.
The symmetric structure of the magnetic head according to the invention may advantageously be used to operate a number of said magnetic ~ heads in an x-y array.
A further preferred embodiment o~ the magnetic head according to the invention is for that purpose characterized in that the parts of the loop on either side of the bridging part are each provided with one or more electric windings.~
A further preferred embodiment of the magnetic head according to the invention is characterized in that in a symmetrically wound head as described above, an auxiliary gap is provided in the loop-shaped second core part exactly at the area o~ the centre of the gap, which auxiliary gap intersects the core part entirely and extends at right angles to the gap.
The above-described constructlon of the head may advan*ageously be used to position the head correctly with respect to an information track to be followed. By providing the auxiliary gap, the actual gap is, as it were, divided into two parts each covering one half of a track to be fol-~50~6Z
lowed. When the head is not positioned correctly with respect to the track, the wo windings provided on the outside of the loop will provide signals which differ in amplitude during a playback operation. The difference sig-nal may then be used to adJust the head in the correct place above the track via a servo mechanism. Once the head has been ad~usted above the track, the d~fference signal is equal to zero and the situation is maintained. The sum signal then represents the complete playback signal.
Still a further preferred embodiment of the device according to the invention is characterized in that at least one recording winding is &rranged in the overlapping region of the gap. Herewith optimum recording properties can be realized.
The invention ~ill be described in greater detail, by way of example, wnth reference to the drawing.
Figure 1 shows a thin-film magnetic head of a known type.
Figure 2 shows a thin-film magnetic head according to the inven-tion.
Figure 3 shows a special construction of the thin-film magnetic head according to the invention.
Figure 4 shows a part of the magnetic head shown in Figure 3 on an enlarged scale.
Figure 1 shows a known construction of a thin-film magnetic head 1 having gap-bounding parts 2 and 4 (made for example, of a nickel-iron alloy) which overlap each other laterally and which are separated at the area of the gap by a thin layer of a rlon-magnetic material 3, (for example glass).
The track width B is determdned by the extent to which the parts 2 and 4 overlap each other. The head 1 furthermore comprises electric windings 5.
Figure 2 shows a thin-film magnetic head 6 according to the inven-tion. It consists of a loop-like magnetic layer 7 which is bridged in the centre by an I-shaped magnetic layer 8. In the region of overlap of the gap, the parts 7 and 8 are separated b~ a strip of non-mQgnetic material 9.
The trackwidth B is determined by the width o~ the part 8.
The provision of identical eiectric windings 10 and 11 makes it possible to operate a plurality of these heads on the same substrate in anx-y arrayO The overlap of the layers 7 and ô has been chosen to be so that an optimum recording field can be realized. For that purpose, the layer 8 ends in the form of a trumpet and the two ends 12 and 13 of the layer 7 extend at an angle of approximately ~5 with respect to the la~er 8.
Such a construction of a head in itself is very suitable for the magnetic recording on comparatively narrow tracks. With the positioning in the usual manner by ~eans of a separate servo track, however, there is a lower limit imposed upon the track width which can be used. When the track becomes narrower than 100 /um it is necessary to derive a servo signal from the signal-carrying track ~tself, since otherwise difficulties occur upon playing back. A particular aspect of the invention resides in the fact that a solution is given to adJust magnetic heads of the type shown above a track recorded in a magnetic medium if the tracks become very narrow.
Identical recording windings 15 and 16 are provided around the two outèr limbs ofthe magnetic circuit of a thin-film magnetic head 14 of the three-limb type ~Figure 3) defined by a loop portion and on I-shaped portion.
AB ~shown on an enlarged scale in Figure ~, the front circuit 17 has two gaps.
The recording-playback gap 11 having a length equal to the track width B and a small auxiliary gap 12, at right angles to 11, in the centre of the mag-netic layer 12. The small auxiliary gap having a width equal to the thick-ness of the magnetic layer thus separates the two outer limbs of the mag-netic circuit from each other in the region of overlap. This has for its result that, as it were, two gaps are formed in line with each other with a length equal to half the track width. When the head is positioned roughly above the track, the difference in the signals of the windings 15 and 16 may be used to adiust the head above the track, while their sum constitutes the play-back signal. When the head deviates from the track, there arises a difference in sign~l amplitude of the windings 15 and 16. One half of the gap l1 then sees more of the recorded track than the other. The difference signal can readjust the head position via a servomechanism. The sign of the difference signal is associated w1th a particular direction of the `
~Q5()~62 deviation.
The magnetic resistance between the two outer limbs in thé front .
circult 17 must be as large as possibleS because when there is a deviation of the head, a maximum difference signal is necessary in view of the com-paratively low flux level during playback. As a recording winding is used a strip l30fanon-magnetisable electrically conductive materi~l present in the region of overlap. The gap 12 must be small so as to minimize during recording the disturbance in the centre of the recording field o~ the gap ll.
Said gap 12 otherwise requires no extra step in the manufacturing process of the head.
As already noted above~ the integration of heads on batches creates the possibility of operating the heads in the form of an array. One head of said array may ensure the adjustment. Due ~o this ad~ustment, the mechanical positioning becomes simpler also in the case of ver~v small tracks, tracks of 5 to 10 /um becoming realisable. In case the head which ensures the adjust-ment is the Figure 3 head it may also fulfil its recording and playback function nor~ally.
From a recording technical poi~t of view the inventive head is further attractive due to the possibility which exists to provide a com-- 20 paratively large number of windings and due to the favourable location of the recording--layback gap.
' :
''' .
.. . . . . . .. ... . . . . . . .. ....
Presently there exists in the industry a need of àn increase of memory storage capacity and hence . : :
o~ magnetic heads for very narrow tracks. The present track width lies in the range of 150 to 200 microns.
; In connection with the above, however, there exists a need of track widths of a few tens of microns. Since, however, magnetic heads suitable for such narrow tracks can no longer be realized in the conventional manner, in which two core parts are placed in line with the interposition o~ a non-magnetisable spacing member and in which the thickness of the core parts determines the track width, the thin-film magnetic head described in the above-mentioned German Patent Application has been proposed. In this mag-netic head, two core parts overlap each other laterally at the area o~ the gap as a result of which the gap wi~th ~-' - ~.
`~ i ) 10~0~6Z
is not determined by the thickness of the core parts but by the extent to which the core parts overlap each other. Such a construction enables the manufacture by means of thin-film methods and photolithographic methods of heads which are suitable for track widths of a few tens of microns. A
drawback is~ however, that the area over which the core parts overlap each other at the site of the gap, which area is large as compared with the thick-ness of the core partsJ adversely influences the playback properties of ~he head: the larger the extent of overlap, the smaller the playback efficiency.
It is the object of the lnvention to provide a head of the above-mentioned kind in which the playback proper~ies are less dependent on the extent of overlap of the core parts than in the known head and which more-over has a number of extra advantages.
For that purpose, according to a broad aspect of the present in-vention, there is provided a thin-film magnetic head comprising a first loop shaped core part of magnetizable material having an upper surface with an outer edge, a second core part of magnetizable material having a lower sur-face and an outer edge and extending from one s.ide of the upper surfaces of the first core part across the upper surface of the first core part to an opposite side of the first core part and overlapping an area of the upper surface of said opposite side of said first core part with a lower surface of said second core part, said second core part being magnetically coupled to said first core part at said one side of said first core part and provid-ing an elongated surface parallel with the upper surface of the first core part and having an elongated outer edge on said elongated surface parallel to said outer edge of said first core part, and a layer of non-magne~izable mater;al between the first and second core parts in the overlapping area thereof, the outer edges of said first and said second core parts forming therebetween a gap elongated in a direction perpendicular to the direction in which the second core part exte~ds across the first core part.
~ith the same overlap area of the gap-bounding , ~5 '' - .
~L~15011 6Z
parts, the magnetic head according to the invention has considerably better playback properties than the known head.
- If` desired, restriction of the overlap is possible by reducing the width of the second core part at the area of and on either side of the first core part.
The width of the second core part, at least at the area of the first core part, preferably is at most half of the width of the first core part.
Although the magnetic coupling of the above-mentioned ends of the core parts may be carried out, for example, by means of a closing yoke on which also an electric winding may be provided, a preferred embodiment of the magnetic head according to the invention is characterized in that the second core part is in the form of a closed loop and that the first core part bridges the loop at least substantially in the centre. Such a con-struction can be realized very suitably and in few steps by means of thin-~ilm methods.
The symmetric structure of the magnetic head according to the invention may advantageously be used to operate a number of said magnetic ~ heads in an x-y array.
A further preferred embodiment o~ the magnetic head according to the invention is for that purpose characterized in that the parts of the loop on either side of the bridging part are each provided with one or more electric windings.~
A further preferred embodiment of the magnetic head according to the invention is characterized in that in a symmetrically wound head as described above, an auxiliary gap is provided in the loop-shaped second core part exactly at the area o~ the centre of the gap, which auxiliary gap intersects the core part entirely and extends at right angles to the gap.
The above-described constructlon of the head may advan*ageously be used to position the head correctly with respect to an information track to be followed. By providing the auxiliary gap, the actual gap is, as it were, divided into two parts each covering one half of a track to be fol-~50~6Z
lowed. When the head is not positioned correctly with respect to the track, the wo windings provided on the outside of the loop will provide signals which differ in amplitude during a playback operation. The difference sig-nal may then be used to adJust the head in the correct place above the track via a servo mechanism. Once the head has been ad~usted above the track, the d~fference signal is equal to zero and the situation is maintained. The sum signal then represents the complete playback signal.
Still a further preferred embodiment of the device according to the invention is characterized in that at least one recording winding is &rranged in the overlapping region of the gap. Herewith optimum recording properties can be realized.
The invention ~ill be described in greater detail, by way of example, wnth reference to the drawing.
Figure 1 shows a thin-film magnetic head of a known type.
Figure 2 shows a thin-film magnetic head according to the inven-tion.
Figure 3 shows a special construction of the thin-film magnetic head according to the invention.
Figure 4 shows a part of the magnetic head shown in Figure 3 on an enlarged scale.
Figure 1 shows a known construction of a thin-film magnetic head 1 having gap-bounding parts 2 and 4 (made for example, of a nickel-iron alloy) which overlap each other laterally and which are separated at the area of the gap by a thin layer of a rlon-magnetic material 3, (for example glass).
The track width B is determdned by the extent to which the parts 2 and 4 overlap each other. The head 1 furthermore comprises electric windings 5.
Figure 2 shows a thin-film magnetic head 6 according to the inven-tion. It consists of a loop-like magnetic layer 7 which is bridged in the centre by an I-shaped magnetic layer 8. In the region of overlap of the gap, the parts 7 and 8 are separated b~ a strip of non-mQgnetic material 9.
The trackwidth B is determined by the width o~ the part 8.
The provision of identical eiectric windings 10 and 11 makes it possible to operate a plurality of these heads on the same substrate in anx-y arrayO The overlap of the layers 7 and ô has been chosen to be so that an optimum recording field can be realized. For that purpose, the layer 8 ends in the form of a trumpet and the two ends 12 and 13 of the layer 7 extend at an angle of approximately ~5 with respect to the la~er 8.
Such a construction of a head in itself is very suitable for the magnetic recording on comparatively narrow tracks. With the positioning in the usual manner by ~eans of a separate servo track, however, there is a lower limit imposed upon the track width which can be used. When the track becomes narrower than 100 /um it is necessary to derive a servo signal from the signal-carrying track ~tself, since otherwise difficulties occur upon playing back. A particular aspect of the invention resides in the fact that a solution is given to adJust magnetic heads of the type shown above a track recorded in a magnetic medium if the tracks become very narrow.
Identical recording windings 15 and 16 are provided around the two outèr limbs ofthe magnetic circuit of a thin-film magnetic head 14 of the three-limb type ~Figure 3) defined by a loop portion and on I-shaped portion.
AB ~shown on an enlarged scale in Figure ~, the front circuit 17 has two gaps.
The recording-playback gap 11 having a length equal to the track width B and a small auxiliary gap 12, at right angles to 11, in the centre of the mag-netic layer 12. The small auxiliary gap having a width equal to the thick-ness of the magnetic layer thus separates the two outer limbs of the mag-netic circuit from each other in the region of overlap. This has for its result that, as it were, two gaps are formed in line with each other with a length equal to half the track width. When the head is positioned roughly above the track, the difference in the signals of the windings 15 and 16 may be used to adiust the head above the track, while their sum constitutes the play-back signal. When the head deviates from the track, there arises a difference in sign~l amplitude of the windings 15 and 16. One half of the gap l1 then sees more of the recorded track than the other. The difference signal can readjust the head position via a servomechanism. The sign of the difference signal is associated w1th a particular direction of the `
~Q5()~62 deviation.
The magnetic resistance between the two outer limbs in thé front .
circult 17 must be as large as possibleS because when there is a deviation of the head, a maximum difference signal is necessary in view of the com-paratively low flux level during playback. As a recording winding is used a strip l30fanon-magnetisable electrically conductive materi~l present in the region of overlap. The gap 12 must be small so as to minimize during recording the disturbance in the centre of the recording field o~ the gap ll.
Said gap 12 otherwise requires no extra step in the manufacturing process of the head.
As already noted above~ the integration of heads on batches creates the possibility of operating the heads in the form of an array. One head of said array may ensure the adjustment. Due ~o this ad~ustment, the mechanical positioning becomes simpler also in the case of ver~v small tracks, tracks of 5 to 10 /um becoming realisable. In case the head which ensures the adjust-ment is the Figure 3 head it may also fulfil its recording and playback function nor~ally.
From a recording technical poi~t of view the inventive head is further attractive due to the possibility which exists to provide a com-- 20 paratively large number of windings and due to the favourable location of the recording--layback gap.
' :
''' .
.. . . . . . .. ... . . . . . . .. ....
Claims (9)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A thin-film magnetic head comprising a first loop shaped core part of magnetizable material having an upper surface with an outer edge, a second core part of magnetizable material having a lower surface and an outer edge and exten-ding from one side of the upper surfaces of the first core part across the upper surface of the first core part to an opposite side of the first core part and overlapping an area of the upper surface of said opposite side of said first core part with a lower surface of said second core part, said second core part being magnetically coupled to said first core part at said one side of said first core part and providing an elongated surface parallel with the upper surface of the first core part and having an elongated outer edge on said elongated surface parallel to said outer edge of said first core part, and a layer of non-magnetisable material between the first and second core parts in the overlapping area there-of, the outer edges of said first and said second core parts forming therebetween a gap elongated in a direction perpendi-cular to the direction in which the second core part extends across the first core part.
2. A magnetic head as claimed in Claim 1, wherein the first core part is in the form of a closed loop and the second core part bridges the loop in the center.
3. A magnetic head as claimed in Claim 1, wherein the width of the first core part at least at the overlapping area of the second core part is at most half of the width of the second core part.
4. A magnetic head as claimed in Claim 2, wherein the portions of the first loop shaped core part on either side of the bridging second core part each have one or more electric windings.
5. A magnetic head as claimed in Claim 1, wherein an auxiliary gap is provided in the loop-shaped first core part exactly at the area of the center of the gap, which auxiliary gap extends at right angles to the gap and inter-sects the first core part entirely.
6. A magnetic head as claimed in Claim 2, characterized in that at least one recording winding is provided in the region of overlap of the gap.
7. A magnetic head as claimed in claim 2, wherein the width of the first core part at least at the overlapping area of the second core part is at most half the width of the second core part.
8. A thin film magnetic record/reproduce head comprising a core having a first and a second core part both in the form of a thin film layer of magnetizable material, said thin film comprising major surfaces connected by edges, said core parts having overlapping major surfaces which form opposed pole pieces adjacent the edges abutting the overlapping major surfaces, a layer of non-magnetizable material being provided between the overlapping major surfaces of said pole pieces so as to define a record/reproduce gap, in which the first core part is I-shaped and in which the second core part is in the form of a continuous single loop, the first core part laterally bridging said loop thereby forming two openings, said record/reproduce gap being defined at one end of the I-shaped first core part and being elongated in a direction perpendicular to the direction in which the first core part extends across the second core part, the first and the second core part being magnetically coupled at the other end of the I-shaped core part in addition to the coupling at said record/reproduce gap, and electric record/reproduce windings being wrapped around the portions of the second core part on either side of the first core part and through each of said openings.
9. An automatic track sensing head comprising a magnetic core having a first and a second core part both in the form of a thin film layer of magnetizable material, said thin film compris-ing major surfaces connected by edges, said core parts having overlapping major surfaces which form opposed pole pieces adjacent the edges abutting the overlapping major surfaces, a layer of non-magnetizable material being provided between the overlapping major surfaces of said pole pieces so as to define a sensing gap, in which the first core part is I-shaped and in which the second core part is in the form of a single loop, the first core part laterally bridging said loop thereby forming two openings, the sensing gap being defined at one end of the I-shaped first core part and being elongated in a direction perpendicular to the direction in which the first core part extends across the second core part, the first and the second core parts being magnetically coupled at the other end of the I-shaped core part in addition to the coupling at the sensing gap, and in which the loop-shaped core part has an aux-iliary gap which extends at right angles to the sensing gap and centrally with respect to it, identical sensing windings being wrap-ped around the portions of the second core part on either side of the first core part and through each of said openings, said sensing windings being adapted for being connected to external circuitry in which their signals are substracted for producing a servo signal.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL7400955A NL7400955A (en) | 1974-01-24 | 1974-01-24 | THIN FILM MAGNET HEAD. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1050162A true CA1050162A (en) | 1979-03-06 |
Family
ID=19820604
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA218,340A Expired CA1050162A (en) | 1974-01-24 | 1975-01-21 | Thin-film head with overlapping legs |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS547565B2 (en) |
| CA (1) | CA1050162A (en) |
| DE (1) | DE2500984A1 (en) |
| FR (1) | FR2259412B1 (en) |
| GB (1) | GB1498681A (en) |
| NL (1) | NL7400955A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3828270A1 (en) * | 1988-08-19 | 1990-02-22 | Siemens Ag | THICK FILM MAGNETIC HEAD |
| JPH10264855A (en) | 1997-03-26 | 1998-10-06 | Aisin Seiki Co Ltd | Vehicle front end modure structure |
| JPH10264857A (en) | 1997-03-26 | 1998-10-06 | Aisin Seiki Co Ltd | Vibicle front end module structure |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3549825A (en) * | 1967-09-18 | 1970-12-22 | Ncr Co | Magnetic transducer with planar spiral coil extending into the gap |
-
1974
- 1974-01-24 NL NL7400955A patent/NL7400955A/en unknown
-
1975
- 1975-01-11 DE DE19752500984 patent/DE2500984A1/en not_active Withdrawn
- 1975-01-21 GB GB260375A patent/GB1498681A/en not_active Expired
- 1975-01-21 CA CA218,340A patent/CA1050162A/en not_active Expired
- 1975-01-22 JP JP880875A patent/JPS547565B2/ja not_active Expired
- 1975-01-23 FR FR7502098A patent/FR2259412B1/fr not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE2500984A1 (en) | 1975-08-14 |
| FR2259412B1 (en) | 1980-05-16 |
| NL7400955A (en) | 1975-07-28 |
| GB1498681A (en) | 1978-01-25 |
| FR2259412A1 (en) | 1975-08-22 |
| JPS50105115A (en) | 1975-08-19 |
| JPS547565B2 (en) | 1979-04-07 |
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