Embodiments described herein relate generally to a disk drive.
A hard disk drive (HDD) functioning as a disk drive includes a rectangular housing, a recording medium (magnetic disk) formed discoid and provided in the housing, and a magnetic head which reads/writes data from/to the recording medium. The housing includes a rectangular base, a top cover formed in the shape of a plate and screwed on the base, and a packing member (gasket) provided between a peripheral edge portion of the base and the top cover.
In such an HDD, part of a side wall of the base, which is adjacent to the magnetic disk, is made to have a smaller wall thickness under constraints of dimensions. In an HDD for a device having a large height, a side wall with smaller thickness has a large height. Thus, in the case where a base having such a side wall is subjected to die-cast molding using aluminum or the like, it is disadvantage in view of fluidity of molding material. Also, part having a small wall thickness is not easily made to ensure a sufficient width of a surface to be in contact with a gasket. This easily causes a disadvantage in retention of air-tightness of the housing.
Various embodiments will be described hereinafter with reference to the accompanying drawings. In general, according to one embodiment, a disk drive comprises a base comprising a bottom wall and a side wall provided along a peripheral edge portion of the bottom wall, a cover comprising a top plate screwed on the side wall, a side plate provided along a peripheral edge of the top plate and opposing to an outer surface of the side wall, and an opening formed in the side plate; a sealing member held between the top plate of the cover and an upper end face of the side wall; and a recording medium rotatably provided at the bottom wall. The side wall of the base comprises a first portion located adjacent to the recording medium, and a projecting portion projecting from the first portion outward of the side wall and located in the opening of the side plate.
A hard disk drive (HDD) according to a first embodiment will be explained as a disk drive in detail.
With respect to the first embodiment, a 2.5-inch HDD incorporating a magnetic disk having a diameter of approximately 2.5 inches (63.5 mm) will be described by way of example. As shown in
The base 12 includes a rectangular bottom wall 12a and a side wall 12b provided along a peripheral edge of the bottom wall 12a, and the base 12 is integrally formed of a metallic material such as aluminum, stainless steel, and the like. The base 12 includes a longitudinal direction and a width direction perpendicular to the longitudinal direction. The side wall 12b of the base 12 includes a pair of long side walls 13a extending in the longitudinal direction and located opposite to each other, and a pair of short side wails 13b extending in the width direction and located opposite to each other. In the entire outer surface of an upper end portion of the side wall 12b, a reception groove 15 is formed.
The top cover 14 is formed in the shape of a rectangular lid which has substantially the same size as the bottom wall 12a of the base 12, by press-forming, for example, a SUS plate having a thickness of 45 mm. The top cover 14 comprises a rectangular top plate 14a, a pair of short side plates 14c and a pair of long side plates 14b which are formed by bending side edge portions of the top plate 14a toward the base 12 at substantially a right angle. The height of each of the side plates is set half or less than that of the side wall 12b of the base 12.
Through holes 18 are formed in four corner portions of the top plate 14a and in positions which are slightly displaced from the centers of side edges of a pair of long sides toward one of the short side walls 13b. The top cover 14 is secured to the side wall 12b of the base 12 by screwing the screws 17, which are inserted in the through holes 18, into threaded holes formed in the side wall 12b of the base 12. That is, the top cover 14 is secured to the base 12 by the screws 17 at both end portions of the short side walls 13b in the longitudinal directions thereof and at substantially central portions of the long side walls 13a in the longitudinal directions thereof. The long side plates 14b and short side plates 14c of the top cover 14 are located in the reception groove 15 of the side wall 12b.
As shown in
In the housing 10, a plurality of magnetic heads 19 and a carriage assembly 22 are provided. The magnetic heads 17 read/write data from/to the magnetic disk 16, and the carriage assembly 22 supports the magnetic heads 17 to be movable relative to the magnetic disk 16. Furthermore, in the housing 10, a voice coil motor (VCM) 24, a ramp load mechanism 25, a latch mechanism 26 and a flexible printed circuit board (FPC) unit 21 are provided. The VCM 24 rotates and positions the carriage assembly 22. The ramp load mechanism 25 holds the magnetic heads 19 in an unload position separated from the magnetic disks 16, when the magnetic heads 19 are moved to an outermost circumferential portion of the magnetic disk 16. The latch mechanism 26 holds the carriage assembly 22 in a retreat position when an impact or the like is applied to the HDD. On the FPC unit 21, electronic components such as a conversion connector are mounted. The carriage assembly 22, the VCM 24, the ramp load mechanism 25, the latch mechanism 26 and the FPC unit 21 are provided in a space between the magnetic disk 16 and the above other of the short side walls 13b in the base 12.
According to the first embodiment, at least one of the long side walls 13a of the base 12 of the housing 10, i.e., both the long side walls 13a in this case, each includes a first portion located adjacent to an outer circumferential edge of the magnetic disk 16, and a projecting portion 50a which projects or is expanded from the first portion and located outward of the side wall 13a. The first portion and the projecting portion 50a are formed integral with each other. The long side plates 14b of the top cover 14 include notches or openings 60a in which the projecting portions 50a are to be located.
The expansion amount (projection length) of each projecting portion 50a is set such that each projecting portion 50a extends more outwardly than the long side edge of the top plate 14a of the top cover 14, and width W, which is the distance between the two projecting portions 50a (the width of the widest part of the base 12 (see
As described above, by virtue of provision of the projecting portions 50a, upper end faces of portions of the long side walls 13a, which correspond to the projecting portions 50a, can be made to have greater widths (they can be made thicker), and their widths can thus be equal to or greater than those of other portions of the long side walls 13a.
As shown in
On the other hand, as shown in
As shown in
In the HDD comprising the above structure, the greater the lengths (widths) D of the notches or openings 60a of the top cover 14, the lower the stiffness of the top cover 14, as a result of which the top cover 14 can be more easily swollen by a reaction force generated when the gasket 20 is compressed. Thus, a substantial gasket compression rate is lowered.
In the HDD having the above structure, the projecting portions 50a are provided in thick and thin wall portions of the side wall 12b of the base 12, the widths of the thick and thin wall portions can be increased to the maximum under constraints regarding external dimensions of the device, and the thicknesses of the side walls can be increased. Furthermore, it is possible to reduce a dimension tolerance by performing cutting processing to form the projecting portions 50. It is therefore expected that the wide walls will be made to have a greater thickness. By increasing the thicknesses of the side walls, the casting performance of the base 12 can be improved. Furthermore, the widths of surfaces of the side walls (upper end faces of the side walls 12b), which are to be in contact with the gasket 20, are increased, and thus the airtightness of the housing 10 can thus be improved. Furthermore, in the first embodiment, three screw holes are formed in each of the long side walls 13a of the base 12, and with respect to the screw holes, the distances between a center screw hole and screw holes formed at the both end portions in the longitudinal direction of the long side walls are set such that the distance between two of the screw holes which are provided on a magnetic disk side on which the magnetic disk 16 is located is greater than that between two of the screw holes which are provided on a carriage assembly side on which the carriage assembly 22 is located. Furthermore, the projecting portion 20a of each long side wall 13a is provided between the screw holes which are separated from each other by the above greater distance, thus improving the aritightness at a region between those screw holes.
By virtue of the above, according to the first embodiment, it is possible to obtain a disk drive whose casting performance is high and whose airtightness is improved.
Next, HDDs according to some other embodiments will he explained. It should be noted that, in other embodiments to be described below, portions like those of the above-described first embodiment are denoted by the same reference numbers and their detailed explanations will be omitted or simplified, and portions different from those of the first embodiment will be mainly explained in detail.
As shown in
The other structural features of the HDD are the same as those of the HDD according to the first embodiment.
Also, in the second embodiment having the above structure, the second projecting portion 50b is provided in part of the long side wall 13b, which is located close to the latch mechanism 26, as a result of which this part can be made to have a greater thickness, and a base side wall can be widened within a range according to external dimension standards of devices. It is therefore possible to improve the casing performance of the base 12. Furthermore, the width of a surface of the base 12 (upper end faces of side walls) which is to be in contact with the gasket 20 is increased, thereby improving the airtightness of the housing.
As shown in FIGS, 13 and 14, in the third embodiment, a long side wall 13a of a base 12 instituting a housing 10 comprises a side-wall portion (third portion) located adjacent to a ramp of a ramp mechanism 25, and a third projecting portion 50c projecting or expanding from the side-wall portion and located outward of the long side wall 13a. The third projecting portion 50c has the same structure as the projecting portion 50a. A notch or a third opening 60c in which the third projecting portion 50c is to be located is formed in a long side plate 14b of a top cover 14. The shape and size of the third opening 60c is the same as those of the above openings 60a. Furthermore, a gasket 20 includes a third bent portion 20c in a position corresponding to that of the projecting portion 50c of the long side wall 13a, the third bent portion 20c being bended outwardly along the third projecting portion 50c. Thereby, at the third projecting portion 50c of the side wall 12b, the gasket 20 contacts with a center portion of an upper end face of the side wall 12b in the width direction of the upper end face.
The other structural features of the HDD are the same as those of the HDD according to the first embodiment.
According to the third embodiment having the above structure, the third projecting portion 50c is provided in part of the long side wall 13b, which is located close to the ramp mechanism 25, as a result of which this part can be made to have a greater thickness, and a base side wall can be widened within a range according to external dimension standards of devices. It is therefore possible to improve the casing performance of the base 12. The width of a surface of the base 12 (upper end faces of side walls) which is to be in contact with the gasket 20 is increased, thereby improving the airtightness of the housing.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
In the above first embodiment, the projecting portions of the base are provided at a pair of long side walls. However, the structure of the projecting portions is not limited to such a structure, and a projecting portion may be provided at only one of the long side walls. In this case also, the casting performance and the airtightness can be improved. Also, in each of the second and third embodiments, as the projecting portion thereof, only the second projecting portion or third projecting portion may be provided.
The number of magnetic disks is not limited to one, and may be set to two ore more, and the number of magnetic heads may also be varied in accordance with the number of magnetic disks provided. The size of the magnetic disk is not limited to 2.5 inches; that is, a magnetic disk having another size may be used. The materials, shapes, sizes, etc. of elements forming the disk drive are not limited to those disclosed with respect to the above embodiments, and can be variously changed as occasion needed.
This application claims the benefit of U.S. Provisional Application No. 62/306,971, filed Mar. 11, 2016, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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62306971 | Mar 2016 | US |