What is claimed is:
1. A printed wiring board, comprising:
an upper wiring substrate having flat surfaces on both sides thereof;
a lower plate body being fixed on the reverse side surface said upper wiring substrate, and being formed with a cavity therein, for receiving an electronic part within an inside thereof;
conductor layers being formed upon the surface of said upper wiring plate, for mounting an electronic part thereon;
conductor layers for mounting an electronic part thereon, being formed on a reverse side surface said upper wiring plate, facing to a region where the cavity is defined by said lower plate body, and being electrically connected with the conductor layers formed on the surface of said upper wiring plate, respectively; and
external electrodes being formed on portions of an outer peripheral surface of said upper wiring plate and said lower plate body formed in one body, and being electrically connected with said conductor layers, respectively, for mounting said printed wiring board on an outside substrate.
2. A printed wiring board, as defined in the claim 1, wherein a through-hole is formed between the surfaces of said upper wiring substrate, interconnecting the conductor layers for mounting an electronic parts on the both sides of said upper wiring substrate, and is filled with resin in an inside thereof.
3. A printed wiring board, as defined in the claim 1, wherein a flat through-hole is formed between the surfaces of said upper wiring plate, interconnecting the conductor layers for mounting an electronic parts on the both sides of said upper wiring substrate, and is filled with resin in an inside thereof.
4. A printed wiring board, as defined in the claim 1, wherein said external electrodes are formed on side-end surfaces of said printed wiring board.
5. A printed wiring board, as defined in the claim 1, wherein said external electrodes are formed on a lower end surface of said printed wiring board.
6. A printed wiring board, as defined in the claim 1, wherein said external electrodes are made up from metal conductors forming bottomed through-holes, each of which is formed on said printed wiring board penetrating through the upper wiring substrate and the lower plate body formed in one body and is closed at a lower end thereof.
7. A printed wiring board, as defined in the claim 1, wherein said lower plate body is formed in either one of a gate-like shape and a frame-like shape in a plane view thereof.
8. A printed wiring board, as defined in the claim 1, wherein said lower plate body has a thickness being a little bit larger than that of the electronic part received within said cavity formed.
9. A printed wiring board, as defined in the claim 1, wherein depth (h) of the cavity of said lower plate body lies within a range from 30% to 90% of a total thickness (t) of said printed wiring board.
10. A printed wiring board, as defined in the claim 1, wherein gaps are hermetically sealed with a molding material including resin, after the electronic part is mounted to be received within the cavity of said lower plate body.
11. A method for manufacturing a printed wiring board, comprising a sequence of the following steps:
(a) forming a through-hole on an upper wiring substrate, on both surfaces of which are lamented conductor foils, and filling up filler within said through-hole formed;
(b) forming predetermined conductor layers for connection of electronic parts thereon on one surface of said upper wiring substrate, which are electrically connected through said through-hole formed;
(c) preparing a lower plate boy, being laminated with conductor foil on at least one surface thereof and formed with a cavity for receiving an electronic part in a part thereof, and bonding said lower plate onto the one surface of said upper wiring substrate with a surface opposing to that being laminated with the conductor foil; and
(d) forming external electrodes for mounting said printed wiring board on an outside substrate, on portions of an outer peripheral surface of said upper substrate and said lower plate body formed in one body, with predetermined conductor layers for connecting electronic parts thereon.
12. A method for manufacturing a printed wiring board, as defined in the claim 11, wherein the through-hole formed in the step of the (a) mentioned above is a flat through-hole, in which conductor layers are formed on both end surfaces of the filler filled within said through-hole.
13. A method for manufacturing a printed wiring board, as defined in the claim 11, wherein said cavity is filled up with resin in advance, when forming the predetermined conductor layers for connecting the electronic parts thereon in said step (d).
14. A method for manufacturing a printed wiring board, as defined in the claim 11, wherein the step for forming said external electrodes in said step (d) includes a step for forming bottomed through-holes, each of which penetrates through said upper wiring substrate and said lower plate body formed in one body and is closed at a lower end thereof.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A magnetic disk device that holds a magnetic disk having servo information written thereon, the magnetic disk device comprising:
a magnetic disk holding unit that holds the magnetic disk having written thereon the servo information as a first set of servo information written, using a predetermined first frequency, in a first set of sectors disposed at predetermined intervals in a rotation direction of the magnetic disk and a second set of servo information written, using a predetermined second frequency, in a second set of sectors disposed at the predetermined intervals in the rotation direction of the magnetic disk at different positions from the positions of the first set of sectors; and
a track selecting unit that creates concentric tracks on the magnetic disk held by the magnetic disk holding unit with the magnetic disk rotation center as the center of the concentric tracks and selects a dividing track that acts as a demarcation for switching areas from which the servo information is read.
2. The magnetic disk device according to claim 1, further comprising a servo-information deleting unit that deletes the servo information that is not read from each of the areas divided by the dividing track selected by the track selecting unit.
3. The magnetic disk device according to claim 1, wherein the magnetic disk holding unit holds the magnetic disk having servo information written inwards in an outer circumference area and outwards in an inner circumference area.
4. The magnetic disk device according to claim 1, further comprising a head evaluating unit that evaluates a head that reads the servo information from the magnetic disk, and
wherein the track selecting unit selects the dividing track that acts as a demarcation for the areas from which the servo information will be read based on information obtained after the evaluation by the head evaluating unit.
5. The magnetic disk device according to claim 1, further comprising a servo demodulating unit that has provided therein a plurality of phase synchronizing circuits corresponding to the write frequencies of the servo information written to the magnetic disk.
6. A servo-information writing device that writes servo information onto a magnetic disk incorporated into a magnetic disk device, the servo-information writing device comprising:
a servo information writing unit that writes a first set of servo information, using a predetermined first frequency, in a first set of sectors disposed at predetermined intervals in a rotation direction of the magnetic disk and a second set of servo information, using a predetermined second frequency, in a second set of sectors disposed at the predetermined intervals in the rotation direction of the magnetic disk at different positions from the positions of the first set of sectors, wherein
the servo information writing unit that writes servo information inwards in an outer circumference area of the magnetic disk and outwards in an inner circumference area of the magnetic disk.
7. A magnetic disk having written thereon servo information for controlling the position and speed of a head of a magnetic disk device, the magnetic disk comprising:
a first area where a first set of servo information is written using a predetermined first frequency, the first area being disposed at predetermined intervals in a rotation direction of the magnetic disk; and
a second area where a second set of servo information is written using a predetermined second frequency, the second area being disposed at the predetermined intervals in the rotation direction of the magnetic disk at a different position from the position of the first area, wherein the servo information is written inwards in an outer circumference area of the magnetic disk and outwards in an inner circumference area of the magnetic disk.
8. A magnetic disk having written thereon servo information for controlling the position and speed of a head of a magnetic disk device, the magnetic disk comprising:
a first area where a first set of servo information is written using a predetermined first frequency, the first area being disposed at predetermined intervals in a rotation direction of the magnetic disk; and
a second area where a second set of servo information is written using a predetermined second frequency, the second area being disposed at the predetermined intervals in the rotation direction of the magnetic disk at a different position from the position of the first area, wherein the first area is a first set of fan-shaped sectors that are narrow towards an inner circumference and broad towards an outer circumference of the magnetic disk and located at the predetermined intervals in the magnetic disk rotation direction, and the second area is a second set of fan-shaped sectors that are narrow towards the inner circumference and broad towards the outer circumference of the magnetic disk and located at the predetermined intervals in the rotation direction of the magnetic disk at different positions from positions of the first set of fan-shaped sectors.
9. A magnetic disk having written thereon servo information for controlling the position and speed of a head of a magnetic disk device, the magnetic disk comprising:
a first area where a first set of servo information is written using a predetermined first frequency, the first area being disposed at predetermined intervals in a rotation direction of the magnetic disk; and
a second area where a second set of servo information is written using a predetermined second frequency, the second area being disposed at the predetermined intervals in the rotation direction of the magnetic disk at a different position from the position of the first area, wherein a dividing track that acts as a demarcation for switching areas from which the servo information will be read divides an inner circumference area from an outer circumference area,
the inner circumference area being an area where the servo information is written at an inner-circumference frequency and the outer circumference area is an area where the servo information is written at an outer-circumference frequency.
10. A manufacturing method of a magnetic disk device applied for manufacturing a magnetic disk device configured to hold a magnetic disk having servo information written thereon, the method comprising:
writing the servo information as a first set of servo information written using a predetermined first frequency in a first set of sectors disposed at predetermined intervals in a rotation direction of the magnetic disk and a second set of servo information written using a predetermined second frequency in a second set of sectors disposed at the predetermined intervals in the rotation direction of the magnetic disk at different positions from the positions of the first set of sectors;
holding the magnetic disk having the servo information written thereon at the writing;
creating concentric tracks on the magnetic disk held at the holding with the magnetic disk rotation center as the center of the concentric tracks and selecting a dividing track that acts as a demarcation for areas from which the servo information is read; and
deleting all the servo information that is not read from each of the areas divided by the dividing track selected at the creating step.