Abstract:
A method for establishing a vacuum in a container includes the following steps. The container having an exhaust through hole defined therein is provided. A sealing cover including a connecting material located on the periphery of the sealing cover is provided. The sealing cover is spaced from the exhaust through hole for form at least gaps between the sealing cover and the exhaust through hole. A vacuum is established in the container. The connecting material is heated. The sealing cover covers the exhaust through hole and the connecting material is cooled. After that the container is packaged.

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to vacuum technologies and, in particular, to a vacuum device and a method for packaging the same. 
     2. Description of the Related Art 
     Some vacuum devices, such as flat panel displays (FPD), are packaged vacuum devices that are used in connection with computers, television sets, camcorder viewfinders, and other electronic devices. Referring to  FIG. 6 , according to the prior art, a typical packaging method of the vacuum device is shown. The packaging method includes the following steps. A pre-packaged container  100  having an exhaust through hole  102  defined thereon is provided. An exhaust pipe  110  is provided and one end of the exhaust pipe  110  is inserted into and fixed in the through hole  102  via low-melting glass powder  108 , and another end of the exhaust pipe  110  is exposed outside the pre-packaged container  100 . A cup-shaped connector  104  and a vacuum pump  106  that connects to the cup-shaped connector  104  is provided. The cup-shaped connector  104  is configured for form a seal between the exhaust pipe  110  and the vacuum pump  106  so as to pump from the pre-packaged container  100  to create a vacuum chamber therein via the vacuum pump  106 . A condensing-light sealing device  112  is provided and is used for heating and softening the exhaust pipe  110  so as to seal one end of the exhaust pipe  110 . One end of the exhaust pipe  110  is sealed to obtain a container under vacuum. 
     The container under vacuum includes the container  100  and the exhaust pipe  110  whose one end is sealed. Alternatively, it can be understood that the pre-packaged container  100  may be directly placed into a vacuum room  114  as shown in  FIG. 7 . After the vacuum room  114  is pumped to create vacuum therein via the vacuum pump  106 , a vacuum also is created in the pre-packaged container  100  at the same time. After that, the exposed end of the exhaust pipe  110  can be sealed via the condensing-light sealing device  112 . 
     However, the exhaust pipe  110  needs to be disposed in the through hole  102  of the container  100  in the above method during packaging the container  100 . Therefore, when finishing the package of the container  100 , a tail of the exhaust pipe  110  may be retained outside of the container  100 , which is disadvantageous in regards of safety and reliability. Furthermore, for expediently sealing the end of the exhaust pipe  110 , the exhaust pipe  110  should have a small diameter, for example, less than 5 mm, which results in expending a lot of time exhausting air from the pre-packaged container  100 . Therefore, the structure of the container  100  becomes complicated and the manufacture cost will be increased. 
     What is needed, therefore, is a packaging method for a vacuum device, which can overcome the above-described shortcomings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present vacuum device and a method for packaging the same are described in detail hereinafter, by way of example and description of an exemplary embodiment thereof and with references to the accompanying drawings, in which: 
         FIG. 1  is a schematic, cross-sectional view of a vacuum device according to an exemplary embodiment; 
         FIG. 2  is a flowchart of a packaging method for the vacuum device of  FIG. 1 ; 
         FIG. 3  is a flowchart of a method for exhausting the air in the low-melting glass powder; 
         FIG. 4  is a schematic, cross-sectional view of the vacuum device of  FIG. 1  connected to a vacuum pump; 
         FIG. 5  is a flowchart of a method for pumping the container to create a vacuum therein; 
         FIG. 6  is a typical vacuum device that is connected with a vacuum pump via a cup-shaped connecter; 
         FIG. 7  is another typical vacuum device that is placed into a vacuum room. 
     
    
    
     DETAILED DESCRIPTION 
     A detailed explanation of a vacuum device and a method for packaging the same according to an exemplary embodiment will now be made with references to the drawings attached hereto. 
     Referring to  FIG. 1 , a vacuum device  30  according to an exemplary embodiment is shown. The vacuum device  30  includes a container  300  having an exhaust through hole  302  defined therein, a sealing cover  308  configured for covering the exhaust through hole  302 , a connecting material  304  and a getter  310 . The getter  310  is disposed on the sealing cover  308  toward the inside of the container  300 . 
     The container  300  includes a housing  312 . The exhaust through hole  302  can be defined in any one sidewall of the housing  312 . The housing  312  may be made a material selected from a group consisting of glass, metal and other material that can be adhered utilizing low-melting glass power. It should be further noted that the vacuum device  30  is an element of a flat panel display, and the housing  312  includes a rear plate, a front plate and spacers disposed between the rear plate and the front plate (not labeled). Some electron elements (not shown) are contained in the housing  312 . In the present embodiment, the housing  312  is comprised of glass. The exhaust through hole  302  can be any opening that is appropriate to the volume of the housing  312 . In the present embodiment, the exhaust through hole  302  has a circular shape and has a diameter of about 2 mm to about 10 mm. However, it is understood too large of a diameter of the exhaust through hole  302  may result in poor reliability. 
     The sealing cover  308  may have a plate shape and a greater area than that of the exhaust through hole  302  for fully covering the exhaust through hole  302 . The sealing cover  308  may be made of glass or metal and have a greater melting point than that of the connecting material  304 . In the present embodiment, the sealing cover  308  is made of glass that has a melting point higher than 600° C. 
     The connecting material  304  may be a layer of low-melting glass powder which is placed along the periphery of the sealing cover  308  manually or via screen-printing method. The connecting material  304  is interposed between the container  300  and the sealing cover  308  so as to adhere the housing  312  with the sealing cover  308 . The connecting material  304  may have some air in therein. During packaging, the connecting material  304  is heated for a predetermined period of time to remove the air therein before mounting the sealing cover  308 . 
     The getter  310  may be mounted on one side of the sealing cover  308  on which the low-melting glass power is located and is configured for absorbing the residual gas in the packaged container  300  after sealing. The getter material generally includes two types: evaporable, and non-evaporable. The evaporable-type getter is mainly made from barium (Ba), magnesium (Ma), strontium (Sr), calcium (Ca), such as barium-aluminum-nickel getter or nitrogen-doped getter. The non-evaporable-type getter is mainly made from titanium (Ti), zirconium (Zr), hafnium (Hf), thorium (Th), vanadium (V), aluminum (al), iron (Fe), or any of their alloys. In the present embodiment, the getter  310  is non-evaporable-type getter made of zirconium, vanadium and iron. Since the getter  310  is directly formed on the sealing cover  308 , a separate space for containing getter materials is not needed in the device, which will simplify the structure of the vacuum device  300  and further decrease the manufacturing costs. 
     Referring to  FIG. 2 , a packaging method according to the exemplary embodiment is shown. The packaging method includes: 
     step S 101 : providing: the pre-packaged container  300 , having the exhaust through hole  302  defined thereon, and the sealing cover  308 , and a layer of the connecting material  304  located on the periphery of the sealing cover  308 ; 
     step S 102 : spacing the sealing cover  308  from the exhaust through hole  302 ; 
     step S 103 : placing the pre-packaged container  300  under vacuum; 
     step S 104 : melting the connecting material  304 ; 
     step S 105 : covering the exhaust through hole  302  with the sealing cover; and 
     steps  106 : cooling down the melted connecting material  304  for providing a seal between the container  300  and the sealing cover  308 . 
     In step S 101 , in some embodiments, the connecting material  304  is firstly mixed with an adhesive to form a slurry. Then, the slurry is coated on the sealing cover  308  manually or via screen-printing method. In one embodiment, the connecting material  304  has a thickness of less than 1 mm. 
     In step S 102 , the connecting material  304  firstly need to be heated so as to remove the air in the connecting material  304 . Referring to  FIG. 3 , the method for removing the air in the connecting material  304  including: 
     step S 201 : placing the sealing cover  308  having the connecting material  304  into a vacuum chamber; 
     step S 202 : heating and melting the connecting material  304  for a predetermined period of time to exhaust the air therein. 
     In step S 202 , the connecting material  304  can be heated by electrically heated wire, infrared light or laser. In the present embodiment, the connecting material  304  is heated via electrically heating or irradiation of the infrared light for about 30 minutes to about 60 minutes so as to exhaust all of gas included therein. Then, the getter  310  can be adhered on the cover with the connecting materials. In the present embodiment, the connecting materials is the low melting point frit. 
     For spacing from the exhaust through hole  302 , at least three rod-shaped supporting elements  306  may be arranged on the periphery of the exhaust through hole  302 . The rod-shaped supporting elements  306  are configured for supporting the sealing cover  308  to form at least one gap between the sealing cover  308  and the housing  312  for efficiently allowing air in the housing  312  to escape. In one embodiment, the supporting elements  306  are also made of low-melting glass and have a height larger than 2 mm. Understandably, other methods can be employed for spacing the exhaust through hole  302  with the sealing cover  308 . The sealing cover  308 , for example, can be held by an element of some kind (not shown). 
     In step S 103 , the pre-packaged container  300  can be pumped via a cup-shaped connector or in a vacuum room. In the present embodiment, referring to  FIG. 4 , the container  300  is placed into the vacuum room  314 . When the vacuum room  314  is pumped to a predetermined vacuum-degree, the pre-packaged container  300  may have a same vacuum-degree with the vacuum room. Referring to  FIGS. 5-6 , in some embodiments, the method for pumping the pre-packaged container  300  to create vacuum therein includes: 
     step S 301 : providing a vacuum room  314  connected to a vacuum pump  316  and a heating device  320  mounted on an inner-wall of the vacuum room  314 ; 
     step S 302 : placing the pre-packaged container  300  and a sealing cover  308  arranged on the exhaust through hole  302  of the pre-packaged container  300  into the vacuum room  314 ; 
     step S 303 : pumping the vacuum room  314  to a predetermined vacuum-degree; 
     step S 304 : heating the pre-packaged container  300  by the heating device for further exhausting the gas in the container  300 . 
     In step S 304 , the heating device  320  can be electrically heating wire, infrared light and/or laser. At the same time, the getter  310  can be activated to absorb gas during heating the pre-packaged container  300 . 
     In step S 106 , when the heating device  320  stops, the temperature of the connecting material  304  and the supporting spacer  306  may decrease and the connecting material  304  and the supporting spacer  306  may solidify. At the same time, the sealing cover  308  is adhered on the exhaust through hole  302 . Thus, the container  300  is packaged by the sealing cover  308  and vacuum has been created in the container  300  having a predetermined vacuum degree. 
     Furthermore, an object  322  may be disposed on the top of the sealing cover  308  to provide an external force for the sealing cover  308 . When the connecting material  304  and the supporting elements  306  are melted, it can fully seal the exhaust through hole  302  via the sealing cover  308 . 
     Since the plate-shaped sealing cover  302  is used for sealing the exhaust through hole  302  of the container  300 , no tail of the exhaust pipe of prior art is retained outside of the container  100 , which is advantageous of safety and reliability. Furthermore, as the exhaust through hole  30  may have a larger diameter, the air in the container  300  can be more quickly removed therefrom. Therefore, the structure of the vacuum device becomes simpler, and the manufacture cost will be decreased. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 
     It is also to be understood that above description and the claims drawn to a method may include some indication in reference to certain steps. However, the indication used is only to be viewed for identification purposes and not as a suggestion as to an order for the steps.