JP7161821B2 - Hard disk substrate plating jig - Google Patents

Description

The present invention relates to a plating jig used when plating hard disk substrates.

As a plating jig for this type of hard disk substrate, a plating shaft is disclosed that is inserted into a through hole in the center of the hard disk substrate to support the hard disk substrate in a suspended state when the hard disk substrate is plated. (See Patent Document 1 and Patent Document 2). The plating shaft is immersed in the plating solution together with the hard disk substrate and is rotationally driven in the plating solution so that the hard disk substrate suspended and supported by the plating shaft is driven to rotate in the plating solution. Grooves are provided along the circumferential direction on the outer peripheral surface of the plating shaft to restrict axial movement of the hard disk substrate suspended from the plating shaft.

The groove described in Patent Document 1 has a V-shaped cross section and is formed with a depth of 5 mm or less from the outer peripheral surface of the plating shaft. Hard disk substrates with a thickness of 0.8 mm or 1.3 mm are used. The groove described in Patent Document 2 has a rectangular cross section, a width of 0.5 mm to 1.5 mm from the outer peripheral surface of the plating shaft, and a depth of 1.5 mm to 3 mm. In particular, for a hard disk substrate having a thickness of 0.8 mm, the groove has a width of 1 mm and a depth of 2.5 mm.

JP-A-9-157857 JP-A-9-71869

However, since the groove described in Patent Document 1 is formed with a V-shaped cross section, the hard disk substrate suspended from the plating shaft does not fit through the through hole of the hard disk substrate with respect to the inner wall surface of the groove. Only the corners of the inner wall to be formed make point contact. Therefore, it is difficult to support the hard disk substrate in a stable posture, and the hard disk substrate is not sufficiently supported. Specifically, as shown in FIG. 7, the groove having a V-shaped cross section includes one inclined surface a formed on the outer peripheral surface g of the plating shaft J and the other inclined surface a facing the one inclined surface a. and an inclined portion K having an inclined surface b. In the grooves disclosed in Patent Document 1, when the hard disk substrate is driven to rotate by the plating shaft, as shown in FIG. There is a problem of generation of so-called nodules in which a and b are scraped off and mixed into the plating solution as foreign matter and attached to the plating surface, resulting in plating failure.

Further, as shown in FIG. 8(b), when a spacer S is provided between the hard disk substrates P, the hard disk substrate P flutters, causing the outer peripheral surface of the hard disk substrate P to stick to the spacer S. There is a problem that nodules are generated in that the spacers S are scraped by the collision, mixed into the plating solution as foreign matter, and attached to the plating surface of the hard disk substrate P, resulting in plating failure.

Similarly to the groove described in Patent Document 1, in the groove described in Patent Document 2, the support of the hard disk substrate is insufficient, and when the hard disk substrate is driven to rotate, the hard disk substrate flutters greatly. may occur. Therefore, there is a risk that the plated surface of the hard disk substrate may be damaged due to collision with other parts, and the plating shaft may be scraped and mixed with the plating solution as foreign matter, which may adhere to the plating surface and cause plating failure. , there is a problem of generation of so-called nodules. In particular, in the case of a thin hard disk substrate having a thickness of about 0.5 mm to 0.63 mm, there is a problem that fluttering occurs remarkably.

SUMMARY OF THE INVENTION The present invention has been made in order to solve such problems. It is an object of the present invention to provide a plating jig for hard disk substrates that can

(1) A plating jig for a hard disk substrate according to the present invention comprises a shaft body having a through hole in the center and inserted into the through hole of the hard disk substrate; and a groove into which a part of the hard disk substrate enters in a state in which the hard disk substrate is suspended and supported, the groove being orthogonal to the axial direction of the shaft main body. is formed with a predetermined width and a predetermined depth in the direction, and a difference between the thickness of the hard disk substrate and the width of the groove is 0.04 mm or more in a state in which a part of the hard disk substrate enters the groove. , and the width of the groove is formed to be 0.3 mm or less.

(2) The hard disk substrate plating jig according to the present invention is the hard disk substrate plating jig according to (1), wherein the depth of the groove is 0.1 mm or more and 1.0 mm or less. It is characterized by

(3) A plating jig for hard disk substrates according to the present invention is the plating jig for hard disk substrates according to (1) or (2), wherein the corners of the openings of the grooves are rounded. characterized by being

(4) A plating jig for hard disk substrates according to the present invention is the plating jig for hard disk substrates according to any one of (1) to (3), wherein the bottom surface of the groove is flat, and the bottom surface of the groove is flat. The bottom surface and the inner wall surface of the groove are perpendicular to each other.

(5) A hard disk substrate plating jig according to the present invention is the hard disk substrate plating jig according to any one of (1) to (4), wherein the material of the hard disk substrate plating jig is , polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyetheretherketone (PEEK), and mixed materials of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE) characterized by being selected from

(6) A method of manufacturing a hard disk substrate according to the present invention is characterized by using the hard disk substrate plating jig according to any one of (1) to (5).

The hard disk substrate plating jig according to the present invention described in the above (1) has a width of 0.04 mm or more and 0.3 mm or less in the width direction clearance between the hard disk substrate and the groove. formed. This configuration suppresses fluttering of the hard disk substrate caused by a large gap exceeding 0.3 mm. Furthermore, it is possible to prevent scratches near the inner diameter due to fluttering. In addition, thinning of the plating thickness due to small gaps of less than 0.04 mm is prevented.

In the hard disk substrate plating jig according to the present invention described in (2) above, grooves having a depth of 0.1 mm or more and 1.0 mm or less are formed. This configuration suppresses the fluttering of the hard disk substrate due to the shallow grooves having a depth of less than 0.1 mm. In addition, thinning of the plating thickness due to deep grooves exceeding 1.0 mm in depth is prevented.

In the hard disk substrate plating jig according to the present invention described in (3) above, the corners of the openings of the grooves are rounded. With this configuration, burrs are prevented from occurring at the corners of the opening, and the hard disk substrate supported in the grooves is prevented from being damaged.

In the hard disk substrate plating jig according to the present invention described in (4) above, the bottom surface of the groove is flat, and the bottom surface and the inner wall surface of the groove are perpendicular to each other. With this configuration, the hard disk substrate is supported in a stable posture, and fluttering is suppressed.

In the hard disk substrate plating jig according to the present invention described in (5) above, the material of the hard disk substrate plating jig is polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF), Polyetheretherketone (PEEK) or a mixed material of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE). This configuration ensures high wear resistance, high chemical resistance to acids and alkalis, high electrical insulation, and high mechanical strength of the plating jig. In addition, this configuration suppresses the generation of foreign matter from the plating jig.

In the method for manufacturing a hard disk substrate according to the present invention described in (6) above, the hard disk substrate is manufactured using the plating jig described in any one of (1) to (5). It supports the hard disk substrate in a stable posture, suppresses fluttering of the hard disk substrate when plating the hard disk substrate, and can suppress scratches near the inner diameter caused by fluttering. Thinning of the plating thickness caused by this is prevented.

According to the present invention, there is provided a hard disk substrate plating jig capable of supporting a hard disk substrate in a stable posture and suppressing fluttering of the hard disk substrate when the hard disk substrate is plated. can provide.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure of the hard-disk board|substrate supported by the plating jig|tool of the hard-disk board|substrate based on embodiment of this invention, Fig.1 (a) shows the perspective view of the hard-disk board|substrate, FIG.1(b) shows a hard-disk substrate. 1 shows a cross-sectional view of a substrate for a device. 1 is a perspective view of a plating jig for a hard disk substrate according to an embodiment of the present invention; FIG. 3A is a side view of the hard disk substrate plating jig according to the embodiment of the present invention, and FIG. 3B is a side view of the hard disk substrate plating jig; FIG. ) is a cross-sectional view cut along AA. FIG. 4A is a side view of a plating jig for a substrate for a hard disk according to an embodiment of the present invention, FIG. 4A showing an inclined portion and a vertical portion of a groove, and FIG. 4B being an enlarged view of the vertical portion of the groove; shows an enlarged side view. FIG. 5A is a diagram of a hard disk substrate plating jig in a state where a hard disk substrate is attached to the hard disk substrate plating jig according to the embodiment of the present invention; FIG. A perspective view is shown, and FIG. 5(b) shows a partial cross-sectional view cut at the groove portion of the plating jig of the hard disk substrate. FIG. 6 is a table showing examples and comparative examples of plating jigs for hard disk substrates according to embodiments of the present invention, FIG. ) indicates the nodule generation rate of Examples and Comparative Examples. FIG. 2 is an enlarged side view of a groove of a plating jig for a conventional hard disk substrate; 8(a) is an enlarged side view of a groove, and FIG. 8(b) is a plating jig for a hard disk substrate mounted with a hard disk substrate; FIG. Fig. 3 shows an enlarged side view of the tool;

A hard disk substrate plating jig 10 according to an embodiment to which the hard disk substrate plating jig according to the present invention is applied will be described with reference to the drawings.

First, the hard disk substrate P to be mounted on the hard disk substrate plating jig 10 will be described. As shown in FIGS. 1(a) and 1(b), the hard disk substrate P is a disc having a thickness of t, an outer diameter of D, and an inner diameter of a central through-hole h of d. The thickness t is about 0.5 mm to 2 mm, the outer diameter D is about 30 mm to 270 mm, and the inner diameter d is about 10 mm to 70 mm.

The hard disk substrate P is made of a plate material such as an aluminum alloy, glass, or ceramic. The hard disk substrate P has high-precision smoothness and surface hardness, and also has high rigidity and impact resistance that can suppress the occurrence of vibration due to high-speed rotation. In order to provide these characteristics, the hard disk substrate P is made of a hard material.

The hard disk substrate P is subjected to surface treatment of the base, plating treatment is performed after the surface treatment, and the surface is polished to a mirror finish after the plating treatment. As the plating treatment, electroless nickel-phosphorus (NiP) plating is performed in this embodiment.

The plating jig 10 for the hard disk substrate P has a plating shaft 20 inserted into the through hole h of the hard disk substrate P, as shown in FIGS. The plated shaft 20 has a shaft body 21, a core member 22, and a pair of caps 23, as shown in FIG. 3(b). A through hole 21a is formed through the shaft body 21 in the axial direction, and a core member 22 is inserted into the through hole 21a. The cap 23 is attached so as to close the opening ends on both sides of the through hole 21a after the core member 22 is inserted.

The shaft body 21 is made of a synthetic resin material, preferably polytetrafluoroethylene (PTFE), more preferably polyvinylidene fluoride (PVDF), and most preferably polyetheretherketone ( PEEK) or a blend of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE). These materials have high chemical resistance to acids and alkalis, and any one of them can be selected from the viewpoints of abrasion resistance, electrical insulation, mechanical strength, and the like. Further, these synthetic resin materials may be mixed materials with other components as long as they do not hinder the production of hard disk substrates.

The shaft body 21 has an outer peripheral surface portion 21b having a smaller diameter than the through hole h of the hard disk substrate P, and a groove 30 is provided in the outer peripheral surface portion 21b. The groove 30 has such a size that the inner peripheral end portion of the hard disk substrate P, which is a part of the hard disk substrate P, can enter when the hard disk substrate P is suspended from the shaft body 21 and supported. The groove 30 is formed with a predetermined width and a predetermined depth in a direction perpendicular to the axial direction of the shaft main body 21 . The width of the groove 30 is formed so that the clearance C in the width direction with P is 0.04 mm or more and 0.3 mm or less.

As shown in FIGS. 3A and 3B, the plurality of grooves 30 are circumferentially continuously provided along the circumferential direction of the shaft body 21, and extend in the axial direction of the shaft body 21. For example, about 60 pieces are provided at predetermined intervals. As shown in FIGS. 4A and 4B, the groove 30 includes an inclined portion 31 inclined from the outer peripheral surface portion 21b toward the axis of the shaft body 21 and an end of the inclined portion 31 on the axis side. It has a vertical portion 32 formed vertically from the portion toward the axis, and a corner portion 33 where the inclined portion 31 and the vertical portion 32 intersect.

The inclined portion 31 has one inclined surface 31a and the other inclined surface 31b facing the one inclined surface 31a, and the angle between the inclined surfaces 31a and 31b is θ (degrees). The opening of the inclined portion 31 is formed with a width W1 (mm). The angle .theta. and the width W1 are appropriately selected based on data such as set parameters such as the structure, size and shape of the plating shaft 10 and experimental values.

When the shaft main body 21 is inserted into the through hole h of the hard disk substrate P and the hard disk substrate P is supported by hanging, the inner peripheral end portion of the hard disk substrate P is easily inserted into the vertical portion 32 of the groove 30. For example, the angle θ is approximately 100 degrees, the width W1 is approximately 6 mm, and the depth DP1 from the outer peripheral surface portion 21b to the corner portion 33 where the inclined portion 31 and the vertical portion 32 intersect is approximately 2.2 mm. Instead of forming the inclined portion 31, the vertical portion 32 may be formed directly from the outer peripheral surface portion 21b of the shaft body 21. FIG.

As shown in FIG. 4B, the vertical portion 32 has one inner wall surface 32a, another inner wall surface 32b facing the one inner wall surface 32a, and a bottom surface 32c. A width W2 (mm) is formed between one inner wall surface 32a and the other inner wall surface 32b (see FIG. 4A), and the vertical portion 32 is formed with a depth DP2 (mm). The width W2 is the difference (W2-t) between the thickness t of the hard disk substrate P and the width W2, that is, the widthwise clearance C between the hard disk substrate P is 0.04 mm or more and 0.3 mm or less. is formed to be The clearance C is the sum of the gap C1 and the gap C2 when the hard disk substrate P is positioned at the center of the width W2.

Therefore, including the thickness t of the hard disk substrate P, the width W2 is formed to be t+C. When the thickness t of the hard disk substrate P is 0.63 mm, the width W2 is preferably 0.67 mm to 0.75 mm. The vertical portion 32 supports the inner peripheral edge of the through hole h of the hard disk substrate P, as shown in FIG. 5(b).

If the clearance C is less than 0.04 mm, the penetration of the plating solution into the gap may be insufficient and the plating thickness may become thin. flaws may occur. If the clearance C exceeds 0.3 mm, the support of the hard disk substrate P by the grooves 30 becomes insufficient, and the hard disk substrate P shakes greatly when the hard disk substrate P is driven to rotate by the plating shaft 20 . There is

The depth DP2 of the vertical portion 32 is represented by the distance (mm) from the corner portion 33 where the vertical portion 32 and the inclined portion 31 intersect to the bottom surface 32c. Specifically, the corner portion 33 is chamfered R to be described later, and the depth DP2 is represented by the distance from the center of the chamfer R of the corner portion 33 to the bottom surface 32c.

The depth DP2 is preferably 0.1 mm or more and 1.0 mm or less, more preferably 0.3 mm or less. If the depth DP2 is less than 0.1 mm, the hard disk substrate P may be insufficiently supported by the grooves 30, resulting in large rattling. If the depth DP2 exceeds 1.0 mm, the penetration of the plating solution into the gap may be insufficient and the thickness of the plating may become thin, resulting in flaws in the vicinity of the ID chamfer.

The bottom surface 32c is formed flat along the axis of the shaft body 21, the bottom surface 32c and one inner wall surface 32a of the vertical portion 32 are orthogonal, and the bottom surface 32c and the other inner wall surface 32b of the vertical portion 32 are orthogonal. is doing. The corners where the bottom surface 32c intersects the one inner wall surface 32a and the other inner wall surface 32b at right angles may be slightly rounded or slightly inclined as long as the corners of the through hole h of the hard disk substrate P do not interfere with each other. good.

The chamfering R of the corner portion 33 may be rounded. By forming the roundness of the corner portion 33, burrs generated at the corner portion are removed and the hard disk substrate P is prevented from being scratched.

The core material 22 is made of a highly rigid material such as fiber-reinforced plastic or metal, and is inserted into the shaft body 21 to increase the mechanical strength of the plated shaft 20 . The pair of caps 23 are made of the same material as the shaft body 21 . As shown in FIG. 2, one of the caps 23 is inserted into a gear provided in the plating equipment, and the gear rotates the plating shaft 20 .

As shown in FIG. 5A, about 60 hard disk substrates P are inserted into the plated shaft 20 corresponding to a plurality of grooves 30 formed in the shaft body 21, for example. Further, the plating shaft 20 is configured such that the spacers S provided in the plating equipment are set between the substrates P for hard disk.

The plating shaft 20 is installed in the plating equipment with the hard disk substrate P and the spacers S set thereon, and is rotatably driven while being immersed in the bath liquid. The hard disk substrate P suspended from the plating shaft 20 is subjected to surface treatment while being driven by the plating shaft 20 to rotate in the bath.

The hard disk substrate P is subjected to (1) degreasing, (2) acid etching, (3) desmutting, (4) 1st zincate, (5) dezincate, (6) 2nd zincate, (7) electroless NiP plating, and The surface of the hard disk substrate P is subjected to surface treatment by being immersed in the bath solution in each step of washing with water between each step. The plating shaft 20 is not limited to the above (1) to (7), but can be used in the step of immersing the hard disk substrate P in the bath and rotating it in the bath. Although it may be used in some steps of, it is preferably used in all steps.

Next, examples and comparative examples of the plating jig 10 for the hard disk substrate P according to the present embodiment will be described. A plating jig according to an example of the plating jig 10 for the hard disk substrate P according to the present embodiment and a plating jig according to a comparative example were produced, and the hard disk substrate P was mounted on the plating jig, and the hard disk substrate P was mounted on the plating jig as shown in FIG. Each item shown in the table of a) was evaluated. Examples 1 to 15 and Comparative Examples 1 to 3 were evaluated respectively. Each example and each comparative example will be described below.

(Example 1)
In Example 1, as shown in FIG. 6A, an aluminum substrate made of an aluminum alloy having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm was used as the hard disk substrate P. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm. Therefore, the widthwise clearance C between the groove 30 and the hard disk substrate P is W2-t, that is, 0.70 mm-0.63 mm=0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.8 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In Example 1, the plating shaft 20 was formed to be shorter than the plating shaft 20 constituting the actual plating equipment so that about ten hard disk substrates P could be supported. Other configurations than the plating shaft 20 were evaluated using an experimental machine configured similarly to the constituent elements of an actual plating facility. The hard disk substrate P was subjected to surface treatment of the base, and after the surface treatment, plating treatment by electroless nickel-phosphorus (NiP) plating was performed in the same manner as the plating treatment in the actual plating equipment.

The hard disk substrate P according to Example 1 configured as described above was evaluated for three items: fluttering of the substrate, scratches near the inner diameter (inner peripheral end), and plating thickness near the inner diameter (inner peripheral end). did Fluttering of the substrate was visually observed on the hard disk substrate P that had undergone the plating process using an experimental machine. A case where the hard disk substrate P hardly shook was indicated by ⊚. Compared to the fluttering of the hard disk substrate P similar to that of Example 1 mounted on the conventional plated shaft J shown in FIG.

Incidentally, the conventional plating shaft J is configured in the same manner as the plating shaft 20 according to the embodiment, and differs therefrom only in the grooves formed in the plating shaft. Specifically, the groove of the conventional plating shaft J has an inclined portion K as shown in FIG. The inclined portion K has one inclined surface a and the other inclined surface b facing the one inclined surface a, and the angle formed by the inclined surface a and the inclined surface b is 100 degrees, The opening of the inclined portion K is formed with a width of 6.6 mm. The depth of the inclined portion K from the outer peripheral surface portion g is 2.2 mm, and the bottom portion of the inclined portion is chamfered R of 0.2 mm.

In addition, compared with the fluttering that occurs in the hard disk substrate P mounted on the conventional plated shaft J, the fluttering of the hard disk substrate P is slightly improved, which is indicated by Δ. Furthermore, fluttering equivalent to fluttering generated in the hard disk substrate P mounted on the conventional plated shaft J is indicated by x.

For flaws near the inner diameter (inner peripheral edge), the vicinity of the corners of the through hole h of the hard disk substrate P, i.e., the vicinity of the ID chamfer, is observed with an optical microscope, and the extent of the flaws is determined using a conventional plating shaft J. It was determined by comparing with the flaws in the vicinity of the ID chamfer of the hard disk substrate P which was plated with a hard disk. A flaw equivalent to the conventional one is indicated by ◯, a flaw slightly larger than that of the conventional one is indicated by Δ, and a number of flaws compared to the conventional one is indicated by ×.

The plating thickness near the inner diameter (inner peripheral edge) was measured by a laser microscope as the height from the outer periphery of the hard disk substrate P to the vicinity of the ID chamfer from the flat portion toward the through hole h, that is, the thickness. For those with a thin thickness near the ID chamfer, the cross section was observed to verify whether the plating thickness was thin compared to the flat portion. Evaluation was made by comparing with the plating thickness near the ID chamfer of the hard disk substrate P plated using the conventional plating shaft J.

The plating thickness equivalent to the conventional one is indicated by ◯, which looks thinner than the conventional one, but the plating thickness is 80% thicker than the flat part as a result of cross-sectional observation. Results When the plating thickness is less than 80% of the thickness of the flat portion, the result is indicated by x.

As a result of evaluating the hard disk substrate P according to Example 1, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as Δ, and plating thickness near the inner diameter was evaluated as Δ. Therefore, it was confirmed that the plated shaft 20 according to Example 1 was satisfactory.

(Example 2)
In Example 2, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.63 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfer R at the corner 33 of the groove 30 was set to 1.0 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.1 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 2 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 2, the fluttering of the substrate was ◯, the flaw near the inner diameter was ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 2 was satisfactory.

(Example 3)
In Example 3, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfer R at the corner 33 of the groove 30 was set to 0.4 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.15 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 3 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 3, the fluttering of the substrate was ◯, the flaw near the inner diameter was ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 3 was satisfactory.

(Example 4)
In Example 4, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfer R at the corner 33 of the groove 30 was set to 0.4 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.25 m. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, the plating process was performed using an experimental machine, and the hard disk substrate P according to Example 4 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 4, the fluttering of the substrate was ◯, the flaw near the inner diameter was ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 4 was satisfactory.

(Example 5)
In Example 5, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.63 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 5 was tested for the three items of fluttering of the substrate, flaws near the inner diameter, and plating thickness near the inner diameter as in Example 1. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 5, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 5 was satisfactory.

(Example 6)
In Example 6, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polytetrafluoroethylene (PTFE).

In the same manner as in Example 1, the plating process was performed using an experimental machine, and the hard disk substrate P according to Example 6 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 6, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 6 was satisfactory.

(Example 7)
In Example 7, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.63 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of a mixed material of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 7 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter as in Example 1. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 7, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 7 was satisfactory.

(Example 8)
In Example 8, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.63 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyvinylidene fluoride (PVDF).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 8 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 8, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 8 was satisfactory.

(Example 9)
In Example 9, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.63 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 at the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.67 mm, and the clearance C was set to 0.04 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 9 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 9, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 9 was satisfactory.

(Example 10)
In Example 10, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.80 mm, and the clearance C was set to 0.17 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.2 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 10 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter as in Example 1. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 10, the fluttering of the substrate was ◯, the scratches near the inner diameter were ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 10 was satisfactory.

(Example 11)
In Example 11, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.90 mm, and the clearance C was set to 0.27 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.2 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 11 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 11, the fluttering of the substrate was Δ, the flaw near the inner diameter was ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 11 was satisfactory.

(Example 12)
In Example 12, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.63 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.90 mm, and the clearance C was set to 0.27 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.8 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 12 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 12, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 12 was satisfactory.

(Example 13)
In Example 13, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.50 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plating shaft 20 was set to 0.55 mm, and the clearance C was set to 0.05 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 13 was tested for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 13, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 13 was good.

(Example 14)
In Example 14, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.50 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.57 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Example 14 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 14, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 14 was satisfactory.

(Example 15)
In Example 15, as in Example 1, the hard disk substrate P was an aluminum substrate having a thickness t of 0.80 mm, an outer diameter D of 95 mm, an inner diameter d of 25 mm, and made of an aluminum alloy. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.87 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.3 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, the plating process was performed using an experimental machine, and the hard disk substrate P according to Example 15 was tested for the three items of fluttering of the substrate, flaws near the inner diameter, and plating thickness near the inner diameter as in Example 1. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Example 15, fluttering of the substrate was evaluated as ⊚, scratches near the inner diameter were evaluated as ◯, and plating thickness near the inner diameter was evaluated as ◯. Therefore, it was confirmed that the plated shaft 20 according to Example 15 was satisfactory.

(Comparative example 1)
In Comparative Example 1, as in Example 1, the hard disk substrate P was made of an aluminum alloy and had a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. A conventional plated shaft J shown in FIG. 7 was used as the plated shaft. Therefore, as shown in FIG. 6A, the vertical portion 32 of the groove 30 similar to that of the first embodiment is not formed, and is indicated as "no groove". A shaft body and a pair of caps constituting the plated shaft J were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Comparative Example 1 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Comparative Example 1, the fluttering of the substrate was x, the flaw near the inner diameter was ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft J according to Comparative Example 1 was not suitable for the plated shaft because the substrate fluttered greatly.

(Comparative example 2)
In Comparative Example 2, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 1.00 mm, and the clearance C was set to 0.37 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 0.2 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, the plating process was performed using an experimental machine, and the hard disk substrate P according to Comparative Example 2 was compared with Example 1 for the three items of fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Comparative Example 2, the fluttering of the substrate was x, the flaw near the inner diameter was ◯, and the plating thickness near the inner diameter was ◯. Therefore, it was confirmed that the plated shaft J according to Comparative Example 2 was not suitable for the plated shaft because the substrate fluttered greatly.

(Comparative Example 3)
In Comparative Example 3, as in Example 1, an aluminum substrate made of an aluminum alloy was used as the hard disk substrate P having a thickness t of 0.63 mm, an outer diameter D of 95 mm, and an inner diameter d of 25 mm. The width W2 of the vertical portion 32 of the groove 30 of the shaft body 21 constituting the plated shaft 20 was set to 0.70 mm, and the clearance C was set to 0.07 mm. The chamfering R at the corners 33 of the groove 30 was set to 0.2 mm. The depth DP2 of the vertical portion 32 of the groove 30 was set to 1.1 mm. A shaft body 21 and a pair of caps 23 constituting the plated shaft 20 were made of polyetheretherketone (PEEK).

In the same manner as in Example 1, plating was performed using an experimental machine, and the hard disk substrate P according to Comparative Example 3 was tested for three items: fluttering of the substrate, scratches near the inner diameter, and plating thickness near the inner diameter. A similar evaluation was performed.

As a result of evaluating the hard disk substrate P according to Comparative Example 3, the fluttering of the substrate was evaluated as ⊚, the flaw near the inner diameter was evaluated as ×, and the plating thickness near the inner diameter was evaluated as ×. Therefore, the plated shaft J according to Comparative Example 3 had good fluttering of the substrate, but the flaw near the inner diameter was x and the plating thickness near the inner diameter was x, confirming that it is not suitable for a plated shaft.

In addition, as shown in FIG. 6(b), plating was performed in actual plating equipment for Examples 5, 7, 9, 15 and Comparative Example 1, and the nodule generation rate (pieces/ surface) was verified. For the nodule generation rate, the surface of the hard disk substrate P was inspected by an optical surface inspection device, and the number of defective protrusions was counted by a scanning electron microscope (SEM) or an atomic force microscope (AFM). The criterion was 0.003 pieces/surface. The optical surface inspection device used was model RS1390 manufactured by Hitachi High-Tech Fine Systems.

The nodule generation rate was 0.002 in Example 5, and 0.001 in Examples 7, 9 and 15, satisfying the criteria for determination, confirming that they are suitable for plated shafts. On the other hand, the nodule generation rate of Comparative Example 1 was 0.010, which did not satisfy the criterion, and was confirmed to be unsuitable for a plated shaft. Note that "-" shown in FIG. 6(b) indicates that the verification has not been performed. , and plating thickness near the inner diameter, good evaluation results have been obtained, so it is presumed that the nodule generation rate also satisfies the criteria.

The effect of the plating jig 10 for the hard disk substrate P according to this embodiment will be described below.

In the plating jig 10 for the hard disk substrate P according to this embodiment, the clearance C between the thickness t of the hard disk substrate P and the width W2 of the groove 30 is 0.04 mm or more and 0.3 mm or less. , grooves 30 are formed. With this configuration, it is possible to suppress the fluttering of the hard disk substrate due to the clearance C exceeding 0.3 mm, and to prevent the plating thickness from being thinned due to the clearance C being less than 0.04 mm. . Furthermore, it is possible to obtain the effect of preventing flaws in the vicinity of the inner diameter due to fluttering.

Further, the plating jig 10 for the hard disk substrate P according to the present embodiment has the grooves 30 with a depth of 0.1 mm or more and 1.0 mm or less. With this configuration, it is possible to obtain the effect of suppressing the fluttering of the hard disk substrate P due to the grooves 30 having a depth of less than 0.1 mm. In addition, it is possible to prevent the thickness of the plating from being thinned due to the grooves 30 having a depth exceeding 1.0 mm.

Further, in the plating jig 10 for the hard disk substrate P according to this embodiment, the corners of the openings of the grooves 30 are rounded. With this configuration, it is possible to prevent burrs from being generated at the corners of the opening and to prevent the hard disk substrate P supported in the grooves 30 from being damaged.

Further, in the plating jig 10 for the hard disk substrate P according to the present embodiment, the bottom surface 32c of the groove 30 is flat, and the bottom surface 32c and one inclined surface 31a and the other inclined surface 31b of the groove 30 are perpendicular to each other. ing. With this configuration, the hard disk substrate P is supported in a stable posture on the bottom surface 32c of the groove 30, and the effect of suppressing fluttering is obtained.

In the hard disk substrate P plating jig 10 according to the present embodiment, the material of the hard disk substrate P plating jig 10 is preferably polytetrafluoroethylene (PTFE), more preferably polyfluoride. vinylidene (PVDF), most preferably composed of polyetheretherketone (PEEK) or a blend of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE). This configuration provides the effect of ensuring high abrasion resistance, high chemical resistance to acids and alkalis, high electrical insulation, and high mechanical strength of the plating jig 10 . In addition, since the plating jig 10 for the hard disk substrate P according to the present embodiment has high wear resistance and chemical resistance, the effect of suppressing the generation of foreign matter from the plating jig 10 can be obtained.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the invention described in the claims. Changes can be made.

10 Plating jig 20 Plating shaft (plating jig)
DESCRIPTION OF SYMBOLS 21... Shaft main body 21a, h... Through hole 21b... Outer peripheral surface part 22... Core material 23... Cap 30... Groove 31... Inclined part 31a... One inclined surface 31b...Other inclined surface 32...Vertical portion 32a...One inner wall surface 32b...Other inner wall surface 32c...Bottom surface 33...Corner C, C1, C2...Clearance D... Outer diameter d... Inner diameter DP1, DP2... Depth P... Hard disk substrate t... Thickness R... Chamfering W1, W2... Width

Claims (4)

a shaft body inserted into the through hole of a hard disk substrate having a through hole in the center; A hard disk substrate plating jig comprising a groove into which a part of
The plating jig is used for hard disk substrates having a thickness of 0.8 mm or less,
The groove is formed with a predetermined width and a predetermined depth in a direction orthogonal to the axial direction of the shaft body, and is provided continuously along the circumferential direction of the shaft body. has a vertical portion having a pair of inner wall surfaces orthogonal to
The thickness of the hard disk substrate and the width of the vertical portion may be different from each other by 0.04 mm or more and 0.3 mm or less in a state where the hard disk substrate is partly inserted into the vertical portion. The width of the vertical part is formed ,
The depth of the vertical portion is 0.1 mm or more and 1.0 mm or less
A plating jig for hard disk substrates, characterized by: 2. The jig for plating a hard disk substrate according to claim 1 , wherein the corners of the opening of the vertical portion are rounded. Plating jig materials for hard disk substrates are polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyetheretherketone (PEEK), polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE). 3. The plating jig for hard disk substrates according to claim 1, wherein the jig is selected from any one of the mixed materials of . 4. A method of manufacturing a hard disk substrate, comprising using the hard disk substrate plating jig according to claim 1 .

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