Abstract
A glass molded product has a plate-like glass 1b having a convex portion provided on the outer peripheral end face, and a resin frame integrally molded to cover the convex portion. The convex portion has a front side pressure receiving surface having a small pressure receiving area and a back side pressure receiving surface having a large pressure receiving area from the resin during integral molding. At the time of integral molding, the plate-like glass is pressed against the upper mold by the resultant force of resin pressure. Even if the lower mold is movable according to the variation of the thickness of the plate-like glass, at least the surface of the plate-like glass does not have a step with the frame, and at least the front side of the glass molded product becomes flat.
Claims
1. A glass molded product comprising: a plate-like glass with a convex portion on an outer peripheral end face; and a frame made of a resin provided by integral molding to cover the convex portion, wherein front surfaces of the plate-like glass and the frame are on the same plane, and back surfaces of the plate-like glass and the frame are on the same plane, and wherein the convex portion is shaped such that a resultant force of pressure received from the resin during the integral molding is directed to the front surface of the plate-like glass.
2. The glass molded product as claimed in claim 1, wherein the convex portion includes: a front side pressure receiving surface having a relatively small area for receiving the pressure of the resin during the integral molding; and a back side pressure receiving surface having a relatively large area for receiving the pressure of the resin during the integral molding.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0022] FIG. 1 is a cross-sectional view showing a glass molded product which the inventor of the present application proposed, a mold for manufacturing the same, and a process of manufacturing the glass molded product using this mold;
[0023] FIG. 2 is a cross-sectional view showing a glass molded product which the inventor of the present application proposed, a mold for manufacturing the same, a process of manufacturing the glass molded product using this mold, and a problem found in this;
[0024] FIG. 3 is a cross-sectional view showing a step of placing the plate-like glass 1 in a mold in the process of manufacturing a glass molded product according to a first embodiment of the present invention;
[0025] FIG. 4 is a cross-sectional view showing a step of injecting a resin into a mold in the process of manufacturing a glass molded product according to the first embodiment of the present invention;
[0026] FIG. 5 is a cross-sectional view showing a step of injecting a resin into a mold in the process of manufacturing a glass molded product according to a second embodiment of the present invention;
[0027] FIG. 6 is a cross-sectional view showing a step of injecting a resin into a mold in the process of manufacturing a glass molded product according to a third embodiment of the present invention; and
[0028] FIG. 7 is a cross-sectional view showing a step of injecting a resin into a mold in the process of manufacturing a glass molded product according to a fourth embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0029] The glass molded products 3b to 3e according to first to fourth embodiments of the present invention will be described with reference to FIGS. 3 to 7. The glass molded products 3b to 3e of these embodiments are panel-shaped products in which resin-made frames 2 are provided on outer peripheral end faces of rectangular plate-like glasses 1b to 1e by integral molding using molds. These molded glass products 3b to 3e can be used as a cover glass for covering devices which are components in various apparatuses. For example, a touch sensor may be disposed on the back side of the molded glass products 3b to 3e to constitute an input device. A liquid crystal display can be arranged to constitute a display device. However, the application is not limited. incidentally, the drawings showing these embodiments are the same as FIGS. 1 and 2 showing the previous invention of the inventor of the present application, and cross-sectional views in which the vicinity of the boundary between the plate-like glass 1b to 1e and the frame 2 is cut by a cut surface parallel to the opening/closing direction of the mold 4.
[0030] A glass molded product 3b according to the first embodiment of the present invention will be described with reference to FIGS. 3 and 4. As shown in FIGS. 3 and 4, the convex portion 10b is provided in the outer peripheral end face of the plate-like glass 1a of the glass molded article 3a as a structure for fixing the frame 2. The convex portion 10b has a front side pressure receiving surface 12 formed by chamfering having an inclination angle of about 50 degrees with respect to the front surface, a rear side pressure receiving surface 13 formed by chamfering having an inclination angle of about 50 degrees with respect to the rear surface, and a vertical surface 14 provided on the boundary between the front pressure receiving surface 12 and the rear pressure receiving surface 13 so as to be perpendicular to the front surface 11a and the rear surface 11b. And the depth of the chamfering is deeper at the back side pressure receiving surface 13 than the front side pressure receiving surface 12, and is about twice. Therefore, the area of the rear side pressure receiving surface 13 is larger than the area of the front side pressure receiving surface 12. Further, the convex portion 10b of the plate-like glass 1a is polished by a relatively rough polishing means (for example, a whetstone of about #800 or the like), and asperities (not shown) are formed on the surface of the convex portion 10b.
[0031] When manufacturing the glass molded product 3b, the mold 4 is used. The mold for producing the glass molded product 3b is the same as the mold 4 used for producing the glass molded product 3a, which is the earlier invention of the inventor of the present application described with reference to FIGS. 1 and 2. First, as shown in FIG. 3, the positioning pin 7 is made to project above the lower mold 6, and the plate-like glass 1b is placed on the inner mold 6b of the lower mold 6 so that the front pressure receiving surface 12 faces up. Then, the vertical surface 14 of the convex portion 10b is abutted against the positioning pin 7 to determine the position of the plate-like glass 1b.
[0032] Next, as shown in FIG. 4, the upper mold 5 and the lower mold 6 are closed, and the positioning pin 7 is pulled into the lower mold 6. The tip of the positioning pin 7 may slightly protrude into the mold 4. Then, the molten resin is injected into the hollow of the mold 4 under a necessary pressure, and the plate-like glass 1b is inserted into the resin frame 2 to be integrally molded.
[0033] In the mold, the convex portion 10b is encased in a resin, and the molten resin enters the fine asperities on the surface of the convex portion 10b to be solidified, and an anchor effect is obtained in which the frame 2 is reliably fixed to the convex portion 10b. The frame 2 is stably held only by the convex portion 10b of the plate-like glass 1b.
[0034] In such an integral molding process, the pressure of the molten resin in the mold 4 is applied to the convex portion 10b. The upward component force (arrow D) of the force applied to the rear pressure receiving surface 13 is larger than the downward component force (arrow C) of the pressure applied to the front pressure receiving surface 12. Therefore, the plate-like glass 1b provided with the convex portion 10b is pushed up as a whole by the force corresponding to the difference between the upward component force and the downward component force. Therefore, the surface 11a of the plate-like glass 1a is in close contact with the lower surface of the upper mold 5. Therefore, the problem described above with reference to FIG. 2, that is, in the production of the glass molded product 3a proposed by the inventor of the present application, the inner mold 6b is sunk by the resin pressure to form a gap (reference sign B) between the surface 11a of the plate-like glass 1a and the lower surface of the upper mold 5 and a step is generated between the plate-like glass 1a and the frame 2 (or burrs can be made on the relevant part), does not occur at all in the first embodiment, and at least the flatness on the surface 11a side of the glass molded product 3b is reliably ensured.
[0035] Although the back surface side of the glass molded product 3b depends on the type of the product using the glass molded product 3b as a component, the back surface 11b which is generally the inner side of the apparatus is not required to have a finish as accurate as the front surface 11a. Therefore, as described above, it is often sufficient to obtain high-precision flatness on the front surface 11a side. Also, if the resin pressure and the elastic force of the buffer material 8 are set to appropriate values, the sinking of the inner mold 6b due to the resin pressure can be avoided or at least reduced. Therefore, it is also possible to make both the front surface 11a and the back surface 11b of the glass molded product 3b flat with the required accuracy.
[0036] In this manner, at least on the front surface 11a, a flat structure having no step between the plate-like glass 1b and the frame 2 is obtained. Incidentally, it is preferable that this flatness is a grade which does not feel a level difference when touching with a finger. As an example for that, the step between the plate-like glass 1b and the frame 2 should just be about 20 micrometers or less, and this condition can be cleared in the first embodiment.
[0037] A glass molded product 3c according to a second embodiment of the present invention will be described with reference to FIG. 5. The glass molded product 3c of the second embodiment is different from the first embodiment in the shape of the convex portion 10c of the plate-like glass 1c. Others are substantially the same as the first embodiment in structure and manufacturing method. As shown in FIG. 5, the convex portion 10c of the plate-like glass 1c is configured by a front pressure receiving surface 12 formed by chamfering having an inclination angle of about 50 degrees with respect to the surface 11a, a rear pressure receiving surface 13 formed by chamfering having an inclination angle of about 20 degrees with respect to the back surface 11b, and a vertical surface 14 provided on the boundary between the front pressure receiving surface 12 and the rear pressure receiving surface 13 so as to be perpendicular to the front surface 11a and the back surface 11b. In addition, the chamfering depth of the rear side pressure receiving surface 13 is three times or more of the chamfering depth of the front side pressure receiving surface 12. Accordingly, the area of the rear side pressure receiving surface 13 is larger than that of the front side pressure receiving surface 12, and larger than the case in the first embodiment.
[0038] In the step of integral molding using the mold 4, the upward component force (arrow D) by the pressure applied to the rear pressure receiving surface 13 is larger than the downward component force (arrow C) by the pressure applied to the front pressure receiving surface 12 and larger than the case of the first embodiment. Therefore, the action of the plate-like glass 1c being pushed upward and in close contact with the lower surface of the upper mold 5 is even more sure than in the first embodiment. The flatness (smallness of the step) of at least the surface 11a of the glass molded product 3c is higher than that of the first embodiment.
[0039] A glass molded product 3d according to a third embodiment of the present invention will be described with reference to FIG. 6. The glass molded product 3d of the third embodiment differs from the first and second embodiments in the shape of the convex portion 10d of the plate-like glass 1d. Others are substantially the same as the first embodiment in structure and manufacturing method. As shown in FIG. 6 which is a cross sectional view, the convex portion 10d of the plate-like glass 1d is represented by a part of a circle. This shape is constituted by a part of a cylindrical surface continuous in the direction perpendicular to the paper surface of FIG. 6. A line L1 passing through the center of this circle and parallel to the front surface 11a and the back surface 11b is at a position closer to the surface 11a than the line L2 passing through the center in the thickness direction of the plate-like glass 1d and parallel to the front surface 11a and the back surface 11b. Therefore, the surface of the convex portion 10d is constituted by the front pressure receiving surface 12 located closer to the surface 11a than the line L1 and the rear pressure receiving surface 13 located closer to the back surface 11b than the line L1.
[0040] In the step of integral molding using the mold 4, since the upward component force by the pressure applied to the rear pressure receiving surface 13 (arrow D) is greater than the downward component force by the pressure applied to the front pressure receiving surface 12 (arrow C), the same effect as that of the first embodiment can be obtained according to the difference between the two component forces.
[0041] A glass molded product 3e according to a fourth embodiment of the present invention will be described with reference to FIG. 7. The glass molded product 3e of the fourth embodiment differs from the first to third embodiments in the shape of the convex portion 10e of the plate-like glass 1e. Others are substantially the same as the first embodiment in structure and manufacturing method. As shown in FIG. 7, the convex part 10e of the plate-like glass 1e is made into the rectangular shape which has steps in the upper and lower sides. That is, the surface 11a side of the convex portion 10e is formed by engraving a relatively small size rectangular shape, and the back surface 11b side of the convex portion 10e is formed by engraving a relatively large size rectangular shape. Therefore, the convex portion 10e is constituted by the front pressure receiving surface 12 parallel to the front surface 11a and the back surface 11b, the back side pressure receiving surface 13 parallel to the front surface 11a and the back surface 11b, and three vertical surfaces 14. The area of the rear side pressure receiving surface 13 is larger than the area of the front side pressure receiving surface 12.
[0042] In the step of integral molding using the mold 4, since the upward force by the pressure applied to the rear pressure receiving surface 13 (arrow D) is greater than the downward force by the pressure applied to the front pressure receiving surface 12 (arrow C), the same effect as that of the first embodiment can be obtained according to the difference between the two forces.
[0043] As explained above, according to each embodiment of the present invention, the front side pressure receiving surface 12 having a relatively small area and the rear side pressure receiving surface 13 having a relatively large area are provided on the convex portions 10b to 10e provided on the outer peripheral end faces of the plate-like glasses 1b to 1e. The plate-like glasses 1b to 1e are pushed up to the surface 11a side by the difference of the force in the vertical direction applied to both sides and brought into close contact with the upper mold 5. Thereby, while preventing the generation of burrs, at least on the surface 11a side, it is possible to prevent the step between the plate-like glasses 1b to 1e and the frame 2 and to obtain necessary flatness reliably.
REFERENCE SIGNS LIST
[0044] 1b-1e plate-like glass [0045] 2 frame [0046] 3b-3e glass molded product [0047] 4 mold [0048] 5 upper mold [0049] 6 lower mold [0050] 6a outer mold [0051] 6b inner mold [0052] 7 positioning pin [0053] 10b-10e convex portion [0054] 11a front surface [0055] 11b back surface [0056] 12 front side pressure receiving surface [0057] 13 back side pressure receiving surface [0058] 14 vertical plane
