JP2000203892A - Glass panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass panel expectable to reinforce a sealing part and readily maintaining a sealing effect. SOLUTION: This glass panel is obtained by arranging a pair of plate glass 1 at a gap in the thickness direction and forming a glass panel main body P1 in which a cavity part V between both a pair of the plate glass is retained in a reduced pressure and closed through a suction hole 6 formed on one plate glass 1A of a pair of the plate glass. In constituting the suction hole 6, one plate glass 1A is provided with a through-hole 1a, a sucking gas tube 7 is stood on the through-hole 1a, a sealing part S of a low-melting glass is formed from the base end part of the glass tube 7 to the peripheral part of the through-hole 1a of one plate glass A. The tip part of the glass tube 7 is heated and melted and closed to give a closed part H. In this case, the coefficient of thermal expansion of a low-melting glass constituting a first sealing part corresponding to one plate glass 1A in the sealing part is set lower than that of one plate glass 1A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method of arranging a pair of glass sheets at an interval in a thickness direction and through a suction port formed in one of the glass sheets. Providing a glass panel main body that is designed to seal the gap under reduced pressure, providing a through hole in the one glass sheet, and forming a suction glass tube in the through hole to constitute the suction port, The present invention relates to a glass panel provided with a low-melting-point glass seal portion over a base end portion and a peripheral portion of the through-hole of the one sheet glass, and provided with a closed portion in which a distal end portion of the glass tube is closed by heating and melting.

[0002]

2. Description of the Related Art As a sheet glass having higher heat insulating performance than a single sheet glass, a double-layer glass integrally formed by interposing an air layer serving as a heat insulating layer between a pair of sheet glasses is known. In this type of glass panel, there is a problem that the thickness of the glass panel itself becomes large, and the aesthetic appearance including sash is easily impaired. Therefore, as a thinner and more heat-insulating material, a plurality of spacers are arranged between a pair of plate glasses, and a sealing made of, for example, low-melting-point glass is provided between the outer edges of the two plate glasses over the entire circumference. It has been considered that a glass panel having a smaller thickness and a smaller heat transmission coefficient is provided by integrally providing a member and reducing the pressure in the gap. Then, in order to reduce the pressure in the gap, a low-melting glass is applied around the glass tube in a state where a glass tube is erected in the through-hole formed in one of the glass plates. After raising the sintering temperature (the temperature lower than the softening point of the glass tube or glass plate) to form the seal portion, lowering the ambient temperature and reducing the pressure in the void portion, as shown in FIGS. In addition, the tip of the glass tube 7 is heated and melted at a temperature equal to or higher than the softening point of the glass tube 7 and closed. In addition, since the glass tube 7 preferably has as little protrusion as possible from the surface of the glass plate so as not to impair the aesthetics and handleability of the glass panel, when the glass tube 7 is heated, heat is applied to the sealing portion S. There is a high danger that the glass will act, and in order to prevent this, a heat shield plate 10 is arranged between the tip of the glass tube 7 and the seal portion S to heat the tip of the glass tube 7.

In a conventional glass panel of this type, the thermal expansion coefficient of the glass tube for suction, the low-melting glass, and the one of the glass plates are set to the same value.

[0004]

According to the above-mentioned conventional glass panel, the suction port protrudes from the surface of the glass plate, and when another object comes into contact with the surface of the glass panel, the suction port hits the suction port. It is easy, and the glass tube and the seal part constituting the suction port may fall off. In particular, the sealing portion has a lower strength than the glass plate, and thus tends to come off. As a preventive measure, a method of putting a cap on the suction port is conceivable. However, it is desired that the seal portion is hardly detached from the glass sheet regardless of the presence or absence of the cap.

Accordingly, it is an object of the present invention to provide a glass panel which can be expected to strengthen the sealing portion and can easily maintain the sealing effect.

[0006]

According to a first feature of the present invention, as shown in FIG. 4, a pair of plate glasses 1A are arranged at an interval in a thickness direction, and the pair of plate glasses 1A are arranged. A glass panel main body P1 in which a gap V between the two glass sheets 1 is depressurized and sealed is provided through a suction port 6 formed in one of the glass sheets 1A. Sheet glass 1
A, a through-hole 1a is provided, a suction glass tube 7 is erected in the through-hole 1a, and a low-melting glass is formed over the base end of the glass tube 7 and the peripheral portion of the through-hole 1a of the one glass plate 1A. In a glass panel provided with a sealing portion S and provided with a closing portion H in which the distal end portion of the glass tube 7 is closed by heating and melting, a first sealing portion corresponding to the one sheet glass 1A among the sealing portions S The thermal expansion coefficient of the low melting point glass constituting S1 is set to be smaller than the thermal expansion coefficient of the one plate glass 1A. The sintering of the seal is performed by raising the ambient temperature of the glass panel to the sintering temperature of the low-melting glass as described above.
The respective volumes of the seal portion and the sheet glass at that time are used as a reference, and the seal portion and the sheet glass are each thermally contracted with subsequent cooling. According to the characteristic configuration of the present invention according to claim 1, since the first seal portion is set to have a smaller thermal expansion coefficient than the sheet glass, the first seal portion has a lower thermal expansion coefficient after sintering the seal portion. In addition, the amount of shrinkage of the plate glass is larger than that of the first seal portion. Therefore, the first seal portion is in a compressed state due to the contraction of the sheet glass, and as a result, the strength of the seal portion is improved. Therefore, it is possible to expect the strength of the seal portion to be higher than that of the conventional one, and it is possible to make the suction port itself difficult to break, and to secure a good sealability, and to prolong the depressurized state of the gap. It can be maintained over a period.

The characteristic structure of the present invention according to claim 2 is, as exemplified in FIG. 4, the thermal expansion of the low melting point glass constituting the second seal portion S2 corresponding to the glass tube 7 in the seal portion S. The coefficient is set to be larger than the thermal expansion coefficient of the glass tube 7. Incidentally, regarding the sealing effect of the sealing portion, not only the relationship between the sealing portion and the sheet glass described above, but also the relationship between the sealing portion and the glass tube is deep.
That is, as the glass tube tip is heated and melted at a high temperature to seal off, the heat is transmitted from the glass tube to the sealing portion. There is a temperature gradient between the glass tube and the sealing portion, and the temperature of the glass tube is higher than that of the sealing portion. Then, in the case of a conventional glass panel in which the thermal expansion coefficient of the glass tube and that of the seal portion are the same value, the expansion amount of the high-temperature glass tube is larger than that of the low-temperature seal portion, and the expansion amount of the glass tube is higher. Due to the difference, the sealing portion restrains the expansion of the glass tube, resulting in a problem that the glass tube is cracked, and the sealing effect is likely to be reduced or the sealing effect cannot be expected. According to the characteristic configuration of the present invention according to claim 2, in addition to being able to achieve the function and effect of the invention according to claim 1, the low-melting-point glass constituting the second seal portion has a low thermal expansion coefficient. ,
Since the coefficient of thermal expansion of the glass tube is set to be larger than that of the glass tube, even when the glass tube is at a higher temperature than the seal portion due to the heating and closing of the glass tube, the amount of thermal expansion of the seal portion is smaller than that of the glass tube. Close to (or increase in) thermal expansion
Therefore, the difference in the amount of thermal expansion between the glass tube and the seal portion is reduced, and it becomes easy to prevent the glass tube from being cracked as in the related art. As a result, it is possible to reduce the sealing failure of the seal portion and maintain the reduced pressure state of the gap portion for a long period of time.

As shown in FIG. 4, a characteristic configuration of the present invention according to claim 3 is that the seal portion S has a different coefficient of thermal expansion between the first seal portion S1 and the second seal portion S2. The first seal portion S1 is provided with a coefficient slope portion S3 having a different coefficient of thermal expansion between the first seal portion S1 and the second seal portion S2.
And the second seal portion S2. According to the characteristic configuration of the present invention according to claim 3, in addition to the effect of the invention described in claim 2, the thermal expansion of the first seal portion and the second seal portion in the seal portion can be achieved. Can be buffered by the coefficient slope portion. That is, even if thermal expansion (thermal shrinkage) distortion due to temperature change occurs in the seal portion due to a difference in thermal expansion coefficient between the first seal portion and the second seal portion, the distortion is caused by the coefficient gradient portion. Dispersion makes it possible to reduce the occurrence of stress concentration at a local portion in the seal portion. As a result, it is possible to prevent a decrease in the durability of the seal portion, and it is easy to maintain the sealing effect for a longer period.

Note that, as described above, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the accompanying drawings.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 4 show an embodiment of a glass panel according to the present invention. A glass panel P comprises a plurality of spacers 2 spaced apart along a plate surface between a pair of glass sheets 1. FIG. The air gap V between the two glass sheets 1A and 1B is reduced and hermetically sealed with respect to the glass panel main body P1 formed by interposing.

The pair of glass sheets 1 are each made of a transparent float glass sheet having a thickness of 3 mm (3 mm glass sheet according to JIS standards, substantially 2.7 to 3.3 mm in consideration of thickness error). A low-melting glass (for example,
A sealing portion 4 of (solder glass) is provided to seal the gap V. The gap V is configured to exhibit a reduced-pressure environment (1.0 × 10 ⁻² Torr or less) by a method of sucking from the suction port 6 formed in the one glass sheet 1A. By the way, the outer peripheral edge of the both glass sheets 1 is
One of the glass sheets 1A is arranged so as to protrude along the direction of the plate surface, and the protruding portion 5 is formed. When the sealing portion 4 is formed, a sealing member ( For example, the outer periphery of the gap V can be efficiently and reliably sealed with the low melting point glass) placed thereon.

The spacer 2 is made of Inconel 718 and is formed in a cylindrical shape.
1.00 mm, and the height is set to 0.1 to 0.5 mm. And since the part which contacts with sheet glass is formed in circular shape, the corner which tends to produce a stress concentration easily in the contact part with both sheet glass 1 can be prevented, and the sheet glass 1 can be made hard to break. On the other hand, the installation interval of the spacer 2 is set to a size of 10 to 25 mm.

Next, the structure relating to the decompression of the gap V will be described with reference to FIG. A suction port 6 for depressurizing the gap V is provided in any one of the pair of plate glasses 1A. To constitute the suction port 6, a glass tube 7 is disposed in the through hole 1a formed in the one glass plate 1A, and the peripheral wall of the through hole 1a and the glass tube 7 are hermetically connected by a low-melting glass 8. It is. The distal end portion 7a of the glass tube 7 is configured as a closed portion H which is heated and melted after decompression and closed. Specifically, a low-melting glass 8 is applied around the through-hole 1a so as to extend between the glass tube 7 and one of the glass sheets 1A (see FIG. 2), and the ambient temperature is raised to about 500 ° C. The low melting point glass 8 is sintered to form a seal portion S. Incidentally, the sealing portion 4 at the outer peripheral portion of the plate glass is also sealed by sintering the applied low-melting glass under the same environment. Then, after waiting for a decrease in the environmental temperature, the gas in the gap V is sucked from the glass tube 7 to sufficiently reduce the pressure, and then the distal end portion 7a of the glass tube 7 is heated and melted to close the closed portion H. It is formed. Regarding the closing of the tip 7a, the tip 7a
Is locally heated (approximately 1000 ° C.). In order to prevent the hot wire from directly hitting the sintered seal portion S and melting, as shown in FIG. The operation is performed in a state where the heat shield plate 10 is arranged so as to cover and hide. After the glass tube 7 is sealed, a protective cap 9 is adhered to the one glass plate 1A so as to cover the suction port 6.

The glass tube 7 has a thickness of 0.1 to 0.1 mm.
It is preferable to use one having a thickness of 1.0 mm. That is, if the thickness exceeds 1.0 mm, it takes time from the temperature rise to the self-fusion when the tip portion 7a is closed, and the temperature rises to unnecessary parts around the case. There is a risk that cracks may occur in the sheet glass 1 or the low-melting glass 8 due to the resulting temperature gradient.
When the thickness is less than 0.1 mm, although the temperature can be easily raised, it is difficult to maintain the shape by self-melting, and the strength is weak, so that the material is extremely easily broken. Incidentally, in this embodiment, the outer diameter of the glass tube 7 is set to 1 to 10 mm, and the height is set to 6 mm or less.

The coefficient of thermal expansion of the glass tube 7 and one of the glass sheets 1A of this embodiment is 92 × 10
⁻⁷ / ° C. (glass tube 7) and 87 × 10 ⁻⁷ / ° C. (one plate glass 1A). As for the seal portion S, when applying the low-melting glass 8, two types of low-melting glasses 8a and 8b having different coefficients of thermal expansion are overlapped as shown in FIG. As shown in FIG. 3, a first seal portion S1 corresponding to the one plate glass 1A and a second seal portion S2 corresponding to the glass tube 7 are formed. Incidentally, the thermal expansion coefficient of the first seal portion S1 is 85 ×
At 10 ^-7 / ° C, the coefficient of thermal expansion of the second seal portion S2 is 96
× 10 ⁻⁷ / ° C., and the low-melting glasses 8a and 8b are mixed with each other between the first and second seal portions, so that the first seal portion S1 and the second seal portion S2 are thermally expanded. A coefficient slope portion S3 is formed in which the coefficient of thermal expansion changes in a gradient between the coefficients. That is, the coefficient of thermal expansion of the coefficient slope portion S3 is close to 85 × 10 ⁻⁷ / ° C. on the first seal portion S1 side, close to 96 × 10 ⁻⁷ / ° C. on the second seal portion S2 side, and It gradually increases from one seal portion S1 side to the second seal portion S2 side. Therefore, at the time of sealing the distal end portion 7a of the glass tube 7, the distal end side of the glass tube 7 expands and expands, whereas the second seal portion S2 in contact with the glass tube 7 has a low temperature. However, since the thermal expansion coefficient is larger than that of the glass tube 7, the glass tube 7 can be easily spread similarly to the glass tube 7, so that a large clamping force can be prevented from acting on the glass tube 7, and cracks occur in the glass tube 7 and the seal portion S. It is possible to prevent the sealing effect from being reduced due to this. The glass panel P
After sintering the seal portion S, the sheet glass 1A shrinks from the first seal portion S1 as it cools, and the first seal portion S1 in this state receives a contraction force from the sheet glass 1A. A compressive internal stress acts to increase the strength, and it is possible to expect an increase in the adhesive force with the sheet glass 1A. That is, according to the glass panel of the present embodiment, it is easy to maintain the sealing effect around the glass tube 7 for a long time, and it is possible to expect the heat insulating effect for many years by maintaining the reduced pressure environment of the gap.

[Another Embodiment] Another embodiment will be described below.

<1> The glass panel of the present invention can be used for a wide variety of applications.
For vehicles (car window glass, railcar window glass, ship window glass) and equipment elements (plasma display surface glass, refrigerator doors and walls, heat insulation doors and walls), etc. It can be used. <2> The glass sheet is not limited to the glass sheet having a thickness of 3 mm described in the above embodiment, and may be a glass sheet having another thickness. The type of glass can be arbitrarily selected. For example, template glass, ground glass (glass having a function of diffusing light by surface treatment), meshed glass or tempered glass, heat ray absorption, ultraviolet ray absorption, heat ray It may be a sheet glass provided with a function such as reflection, or a combination thereof. The composition of the glass may be soda silicate glass (soda lime silica glass), borosilicate glass, aluminosilicate glass, or various crystallized glasses. <3> The plate glass is not limited to the one plate glass and the other plate glass having different lengths and widths, and is not limited to those having the same size. You may. The two glass sheets may be overlapped so that the edges are aligned. Further, a glass panel may be configured by combining one plate glass and the other plate glass having different thickness dimensions. <4> The spacing member is not limited to the spacer made of Inconel 718 described in the above embodiment, and may be, for example, stainless steel, other metals, quartz glass, ceramics, or the like. In short, any material may be used as long as it is not easily deformed so that the two glass sheets do not come into contact with each other under an external force. <5> The coefficients of thermal expansion of the low-melting glass 8, the glass tube 7, and one of the glass sheets 1A of the seal portion S are not limited to the values described in the above embodiment. For example, as described in the previous embodiment, the thermal expansion coefficient of the first seal portion S1 is set to be smaller than the thermal expansion coefficient of the second seal portion S2. The setting may be larger than the coefficient of thermal expansion of the second seal portion S2, or the setting may be equal (or substantially equal). Therefore,
A configuration in which the coefficient slope is not provided is also possible. However, the coefficient of thermal expansion refers to the average coefficient of thermal expansion in the temperature range from room temperature to the yield point of the low-melting glass (low-melting glass used for the sealing portion) for each of the sealing portion, the glass tube, and one of the glass sheets. . Further, in forming the seal portion S, in addition to the method of applying and sintering the paste-like low-melting glass described in the above embodiment, a ring-shaped low-melting glass molded body 15 is formed in advance. It is also possible to adopt a method of externally fitting the glass tube 7 and sintering it. At this time, a ring-shaped molded body 15 made of low melting point glass is used.
May have a cylindrical or frusto-conical shape as shown in FIGS. Further, as shown in FIG. 7, low-melting glasses 8a and 8b having different coefficients of thermal expansion may be integrally formed or may be formed separately.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a glass panel.

FIG. 2 is a cross-sectional view showing a main part of the glass panel.

FIG. 3 is a sectional view showing a main part of the glass panel.

FIG. 4 is a sectional view showing a main part of the glass panel.

FIG. 5 is a sectional view of a main part showing a seal portion of another embodiment.

FIG. 6 is a sectional view of a main part showing a seal portion of another embodiment.

FIG. 7 is a sectional view of a main part showing a seal portion of another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet glass 1A One sheet glass 1a Through-hole 6 Suction port 7 Glass tube H Closed part P1 Glass panel main body S Seal part S1 First seal part S2 Second seal part S3 Coefficient slope V gap

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takahiro Sonoda 3-1-1, Doshumachi, Chuo-ku, Osaka-shi, Osaka Inside Nippon Sheet Glass Co., Ltd. (72) Takahiro Asai 3-chome, Doshumachi, Chuo-ku, Osaka-shi, Osaka No. 5-11 Nippon Sheet Glass Co., Ltd. F-term (reference) 4G061 AA09 AA13 AA18 BA01 BA02 BA07 BA09 BA10 CB02 CD02 CD23 DA24 DA26 DA30

Claims (3)

[Claims] 1. A pair of glass sheets are arranged at an interval in a thickness direction, and a pressure gap between the glass sheets is reduced and sealed through a suction port formed in one of the glass sheets. The illustrated glass panel main body is provided, and in order to constitute the suction port, a through hole is provided in the one plate glass, a suction glass tube is erected in the through hole, and a base end portion of the glass tube and the one end are provided. A glass panel provided with a low-melting-point glass seal portion over the periphery of the through-hole of the sheet glass, and a closed portion provided by heating and melting the front end portion of the glass tube and closing the glass tube, wherein: A glass panel wherein the low-melting-point glass constituting the first seal portion corresponding to the one sheet glass has a smaller coefficient of thermal expansion than the one sheet glass. 2. The thermal expansion coefficient of the low melting point glass constituting the second seal portion corresponding to the glass tube among the seal portions is set to be larger than the thermal expansion coefficient of the glass tube. The glass panel as described. 3. The seal part has a different coefficient of thermal expansion between the first seal part and the second seal part, and is inclined between the first seal part and the second seal part. The glass panel according to claim 2, further comprising a slope coefficient portion having a different thermal expansion coefficient.