Cover gasket for hard disk device

The present invention relates to a cover gasket used in a hard disk drive.

[0002] Conventional technology<u style="single">Figure 10</u>As shown in, a cover gasket 1 for a hard disk device, which is formed by combining a rubber 3 as a sealing gasket with the top cover 2 of a hard disk, is known. As a means of combining the cover 2 and the rubber 3, the rubber 3 is combined with the cover 2. , Rubber 3 with a stainless steel core, stacked on cover 2, cover 2 coated with urethane foam or liquid rubber and cured, or cover 2 and rubber Examples thereof include those in which 3 and 3 are post-bonded using an adhesive.

[0003] Among them, when the cover 2 and the rubber 3 are post-bonded using an adhesive, there is a problem of poor adhesion due to the protrusion of the adhesive.

[0004] The mechanism by which the adhesive squeezes out and the rubber 3 peels off is as follows.

That is,<u style="single">Figure 11</u>As shown in, when the cover 2 and the rubber 3 are post-bonded using an adhesive (not shown), an adhesive is applied to the adhesive surface 3a of the rubber 3 and the cover 2 and the rubber 3 are bonded to the adhesive jig. After setting to 11,<u style="single">Figure 12</u>As shown in, heating and bonding are performed while applying a load P from the upper part (upper jig 12 side). At this time, if the magnitude of the above load P is too large, the rubber 3 is strongly pressed against the lower jig 13 to the outside. Excessive force P in the direction₁Occurs. Therefore, this excess force P₁The adhesive 4 applied to the adhesive surface 3a of the rubber 3 is scraped out, which causes the adhesive 4 to squeeze out. Further, along with this, the adhesive film interposed between the cover 2 and the rubber 3 becomes thin, which leads to a decrease in the adhesive force. Further, when the top cover 2 is taken out from the jig 11, the rubber 3 elastically recovers.<u style="single">Figure 13</u>Shear stress P in the direction opposite to that at the time of bonding as shown in₂Is generated, and this is the cause of the peeling of the rubber 3.

[0006] The load P, that is, the pressing force of the adhesive portion controls the magnitude of the load so that the adhesive 4 does not squeeze out or the adhesive film becomes thin as described above, and the rubber 3 To prevent pushing too much, the jig 11 receives 14 (<u style="single">Figure 11</u>See).

[0007] However, if the flatness of the adhesive portion of the cover 2 is not good, a large pressing force is required to adhere the entire surface of the adhesive portion, and even if the jig 11 is provided with the receiver 14, the cover 2 is partially provided. Due to the warp, the adhesive 4 may protrude more or the adhesive 4 may have a thinner film thickness. The cover 2 is formed by press molding, but especially when the cover 2 is press-molded with a stainless steel plate or the like, springback occurs after pressing, so that the flatness thereof is sufficient to enable good adhesion. It is difficult to improve.

[0008] Further, when the adhesive 4 is applied to the adhesive surface, the adhesive surfaces are bonded, pressed and placed on a hot plate, the pressing force and the surface tension of the adhesive 4 are initially balanced and adhered. The adhesive 4 that remains between the surfaces loses surface tension as the temperature rises, becomes unbalanced at a certain temperature, and the adhesive 4 is pushed out of the adhesive surface. At this time, since the adhesive 4 is extruded first from the weakly balanced portion, and because the viscosity of the adhesive 4 also decreases due to the temperature rise, the adhesive 4 is uniformly extruded from the entire outer periphery of the adhesive surface. Instead, it is extruded from multiple locations so that it pops out unevenly. Therefore, as a result, the state after protrusion is<u style="single">Figure 14</u>As shown in the model diagram of, the adhesive 4 is shaped like a centipede's leg protruding from both sides of the rubber 3 in a jagged manner.

[0009] Further, in Japanese Patent Publication No. 2517797, a cover gasket for post-bonding a cover and rubber using an adhesive is published, but the conventional technique published in this publication causes the adhesive to squeeze out. The rubber burr is coated and fixed by the adhesive that has squeezed out, and the adhesive that has squeezed out is positively tolerated.

[0010] [Patent Document 1] No. 2517797 Japanese Patent Publication [0011] [Problems to be Solved by the Invention] In view of the above points, the present invention post-bonds a cover and rubber using an adhesive. It is an object of the present invention to provide a cover gasket for a hard disk device, which can prevent the adhesive from squeezing out and the rubber from peeling off as much as possible.

[Means for Solving the Problems] In order to achieve the above object, the present invention<u style="single">Claim 1</u>The cover gasket for a hard disk device, which is formed by post-bonding the cover and rubber with an adhesive, prevents the adhesive applied to the adhesive surface of the cover or rubber from squeezing out due to the pressing force during bonding. Make a recess on the adhesive surface<u style="single">The recess is provided at the widthwise end of the rubber adhesive surface.</u>It is characterized by that.

[0013] If a recess is provided on the adhesive surface of the cover or rubber as in the cover gasket according to claim 1 of the present invention having the above configuration, the adhesive will be applied to the recess even if the pressing force at the time of bonding is large. Since it is stored, it is possible to minimize the squeeze out of the adhesive. In addition, since a part of the adhesive is stored in the recess, the adhesive film thickness becomes thicker, so that the adhesive force can be strengthened.<u style="single">The recess is provided at the widthwise end of the rubber adhesive surface, so the recess is</u>It will also open on the side of the rubber.

[0014] The post-adhesion is to form the cover and the rubber individually into a product shape and then bond the two.

BEST MODE FOR CARRYING OUT THE INVENTION Next, examples of the present invention will be described with reference to the drawings.

【0016】<u style="single">first</u>Example···<u style="single">Figure 1</u>Of the present invention<u style="single">first</u>The cover gasket 1 according to the embodiment is shown in a state in which the cover 2 and the rubber (also referred to as a gasket in a narrow sense) 3 which are the components thereof are set on the adhesive jig 11 for post-bonding using the adhesive 4. ,<u style="single">Figure 2</u>As shown in the enlarged view, recesses 5 for storing the adhesive, which are chamfered, are symmetrically provided in advance at both ends of the adhesive surface 3a of the rubber 3 in the width direction.<u style="single">Figure 1</u>As shown in the above, the cover 2 and the rubber 3 are adhered to each other in a state where a part of the adhesive 4 applied to the adhesive surface 3a of the rubber 3 is stored in the recess 5.

[0017] The cover 2 is formed by press-molding a material made of stainless steel, an aluminum alloy, brass plated with electroless nickel, or a laminate thereof.

[0018] The rubber 3 has a relatively wide flange portion 3b as an adhesive surface 3a to the cover 2, and a relatively narrow lip portion 3c integrally molded at the center in the width direction on the opposite side. It is molded from FKM (fluororubber), EPDM (ethylene / propylene / diene rubber), NBR (acrylonitrile / butadiene rubber), urethane rubber, etc., and its hardness is set to about Hs20 to 80. Further, the width dimension in the cross-sectional shape is formed to be about 1.5 to 2 mm in actual size, and the height dimension is also formed to be about 1.5 mm in actual size.

[0019] The chamfered recess 5 is provided along the plane layout of the rubber 3 over the entire length of the rubber 3, and the height dimension in the cross-sectional shape is about 0.2 mm or less in actual size. It is formed in. Further, the chamfered recess 5 has a shape such that the widthwise end portion of the adhesive surface 3a is cut diagonally, and has an inclined surface 5a having a straight cross section, and the adhesive surface of the inclined surface 5a. It is even better to set the tilt angle θ with respect to 3a to 20 to 70 degrees and set it to 40 degrees. The reason for setting the inclination angle θ to such a numerical value is that the discharge resistance of the adhesive 4 can be suppressed and a sufficient volume for storing the adhesive 4 can be secured. In this cross-sectional shape, the inclined surface 5a intersects the adhesive surface 3a at a non-right angle, and the outlet of the adhesive 4 in the protruding direction gradually widens in the recess 5.

[0020] A one-component thermosetting type epoxy adhesive is often used as the adhesive 4, and the adhesive 4 is applied to the rubber 3 by transfer by a stamp or the like.

[0021] Further, the illustrated adhesive jig 11 is composed of a combination of the upper jig 12 and the lower jig 13, and the cover 2 is sandwiched between the upper jig 12 and the upper jig 13 on the upper surface of the lower jig 13 at the time of bonding. A receiver 14 for limiting the amount of compression of the rubber 3 is provided, a support portion 15 for supporting the rubber 3 at the time of bonding, a negative pressure suction port 16, and the like are provided.

[0022] In the cover gasket 1 having the above configuration, as described above, recesses 5 for storing the adhesive, which are chamfered, are symmetrically provided at both ends of the adhesive surface 3a of the rubber 3 in the width direction. When the adhesive 4 is applied to the adhesive surface 3a of the rubber 3, a part of the adhesive 4 is stored in the chamfered concave portion 5, and the adhesive is bonded in this state. Therefore, even if the pressing force at the time of bonding is large, the adhesive 4 is stored in the chamfered recess 5, so that the protrusion of the adhesive 4 is minimized as shown in the model diagram of FIG. be able to. Further, since the adhesive 4 is stored in the chamfered recess 5, the coating area of the adhesive 4 is increased, and thus the adhesive force can be strengthened, whereby peeling of the rubber 3 can be suppressed. ..

[0023] In addition, the above<u style="single">first</u>In the embodiment, the recess 5 is provided as a chamfered shape at the widthwise end of the adhesive surface 3a of the rubber 3, but the recess 5 may be a notch shape as illustrated below.

【0024】<u style="single">second</u>Example···<u style="single">Figure 4</u>As shown in, the inner surface of the recess 5 is formed by a combination of an inclined surface 5a having a linear cross section having a predetermined inclination angle with respect to the adhesive surface 3a and a horizontal plane 5b having a linear cross section parallel to the adhesive surface 3a. Has been done. This cross-sectional shape is the above<u style="single">first</u>Similar to the embodiment, the inclined surface 5a intersects the adhesive surface 3a at a non-right angle, and the outlet of the adhesive 4 in the protruding direction gradually widens in the recess 5.

【0025】<u style="single">Third</u>Example···<u style="single">Figure 5</u>As shown in the above, the inner surface of the concave portion 5 is formed by the curved surface 5c having a convex curved cross section. In this cross-sectional shape, the curved surface 5c intersects the adhesive surface 3a at a non-right angle, and the outlet of the adhesive 4 in the protruding direction gradually expands in the recess 5.

【0026】<u style="single">Fourth</u>Example···<u style="single">Figure 6</u>As shown in the above, the inner surface of the concave portion 5 is formed by the curved surface 5d having a concave curved cross section. This cross-sectional shape is the above<u style="single">Third</u>Similar to the embodiment, the curved surface 5d intersects the adhesive surface 3a at a non-right angle, and the outlet of the adhesive 4 in the protruding direction gradually expands in the recess 5.

【0027】<u style="single">Fifth</u>Example···<u style="single">Figure 7</u>As shown in the above, the inner surface of the concave portion 5 is formed by the curved surface 5d having a concave curved cross section. In this cross-sectional shape, the curved surface 5d intersects the adhesive surface 3a at a right angle.

【0028】<u style="single">Sixth</u>Example···<u style="single">Figure 8</u>As shown in the above, the inner surface of the recess 5 is formed by a combination of a vertical surface 5e having a straight cross section perpendicular to the adhesive surface 3a and a horizontal surface 5b having a straight cross section parallel to the adhesive surface 3a. In this cross-sectional shape, the vertical surface 5e intersects the adhesive surface 3a at right angles.

【0029】<u style="single">Seventh</u>Example···<u style="single">Figure 9</u>As shown in, a vertical surface 5e having a straight cross section perpendicular to the bonding surface 3a, an inclined surface 5a having a linear cross section having a predetermined inclination angle with respect to the bonding surface 3a, and parallel to the bonding surface 3a. The inner surface of the recess 5 is formed by a combination of horizontal planes 5b having a straight cross section. In this cross-sectional shape, the vertical surface 5e intersects the adhesive surface 3a at right angles.

[0030] All of the recesses 5 having these cross-sectional shapes have an effect of storing the adhesive 4 in the recesses 5, and in particular, the above-mentioned<u style="single">1st, 2nd, 3rd or 4th</u>As in the embodiment, if the inclined surface 5a or the curved surface 5d intersects the adhesive surface 3a at a non-right angle, and the outlet of the adhesive 4 in the protruding direction gradually expands in the recess 5, this is assumed. The discharge resistance of the adhesive 4 at the outlet is small, so that the adhesive 4 applied to the adhesive surface 3a of the rubber 3 gradually flows out from between the rubber 3 and the cover 2 into the recess 5 before the temperature rises. In addition, the pop-out phenomenon of the adhesive 4 can be suppressed particularly effectively. Further, the adhesive 4 is a highly viscous fluid and flows out along the angled wall of the rubber 3, so that the phenomenon of the adhesive 4 popping out can be suppressed particularly effectively. It is considered that this effect can be expected when the crossing angle (θ above) is within the range of about 20 to 70 degrees.

[Effects of the Invention] The present invention has the following effects.

That is, the present invention having the above configuration.<u style="single">Claim 1</u>In the cover gasket made by, the adhesive that is applied to the adhesive surface of the cover or rubber is prevented from squeezing out due to the pressure applied during adhesion in the gasket that is made by post-bonding the cover and rubber with an adhesive. To<u style="single">The recess is provided at the widthwise end of the rubber adhesive surface.</u>Therefore, when the adhesive is applied to the adhesive surface, a part of the adhesive is stored in this recess, and the adhesive is adhered in this state. Therefore, even if the pressing force at the time of bonding is large, the adhesive is stored in the recesses, so that the protrusion of the adhesive can be minimized. In addition, since a part of the adhesive is stored in the concave portion, the adhesive film thickness becomes thicker, so that the adhesive force can be strengthened, and thus it is possible to suppress the occurrence of peeling of the rubber.

[0033] [Simple description of drawings]<u style="single">[Figure 1]</u>Of the present invention<u style="single">first</u>Cross-sectional view of the main part showing the bonding process of the cover gasket according to the embodiment.<u style="single">[Figure 2]</u>Cross-sectional view of rubber, which is a component of the cover gasket<u style="single">[Fig. 3]</u>Comparative model diagram showing the completed state of the cover gasket<u style="single">[Fig. 4]</u>Of the present invention<u style="single">second</u>Cross-sectional view of rubber which is a component of the cover gasket according to the embodiment.<u style="single">[Fig. 5]</u>Of the present invention<u style="single">Third</u>Cross-sectional view of rubber which is a component of the cover gasket according to the embodiment.<u style="single">[Fig. 6]</u>Of the present invention<u style="single">Fourth</u>Cross-sectional view of rubber which is a component of the cover gasket according to the embodiment.<u style="single">[Fig. 7]</u>Of the present invention<u style="single">Fifth</u>Cross-sectional view of rubber which is a component of the cover gasket according to the embodiment.<u style="single">[Fig. 8]</u>Of the present invention<u style="single">Sixth</u>Cross-sectional view of rubber which is a component of the cover gasket according to the embodiment.<u style="single">[Fig. 9]</u>Of the present invention<u style="single">Seventh</u>Cross-sectional view of rubber which is a component of the cover gasket according to the embodiment.<u style="single">[Fig. 10]</u>Cross-sectional view of the main part of the cover gasket according to the conventional example<u style="single">[Fig. 11]</u>Cross-sectional view of the main part showing the bonding process of the cover gasket<u style="single">[Fig. 12]</u>Explanatory drawing which shows the action direction of a pressing force in the bonding process of the cover gasket.<u style="single">[Fig. 13]</u>Explanatory drawing showing the direction of shear stress generation in the bonding process of the cover gasket.<u style="single">[Fig. 14]</u>Comparative model diagram showing the completed state of the cover gasket<u style="single">[Explanation of symbols]</u><u style="single">【0034】</u><u style="single"> 1 Cover gasket for hard disk drive</u><u style="single"> 2 cover</u><u style="single"> 3 rubber</u><u style="single"> 3a Adhesive surface</u><u style="single"> 4 Adhesive</u><u style="single"> 5 recess</u>