Waterproof mechanism for satellite antenna

A waterproof mechanism for a satellite antenna is to separate a waterproof cover of the known technology into two components of a fixing cover and a thin wall cap used for compressing an O-ring, cause the thin wall cap and the O-ring to be combined closely and stably on the upper end of a wave-guide tube, and enable the stability and the strength of the entirety to be increased. But, the thin wall cap is unnecessary to have a same thickness as the fixing cover. Therefore, the thickness of the thin wall cap can approximately be reduced to 3 mm. This can increase broadly the passing rate of satellite signal and allow a low noise block with integrated feed (LNBF) to have a better satellite signal receiving effect.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a satellite antenna, and more particular to a waterproof mechanism for a satellite antenna.

2. Description of Related Art

A general satellite antenna system is to place a low noise block with integrated feed (LNBF) at a plane where the focus of an antenna dish is located so as to receive satellite signals.

U.S. Pat. No. 6,570,542 discloses an integrated dual-directional feed horn, for receiving radio frequency (RF) signals from two satellites in a small angle, includes a first LNBF and a second LNBF.

U.S. Pat. No. 6,191,753 discloses a rigid cover for satellite antennas. The cover prevents rain from passing between a dish member and a converter assembly of the satellite antenna. The cover may be designed for a particular style of the satellite antenna. The cover may be designed for a particular style of satellite antenna or, preferably, have a mounting portion adapted to accommodate a plurality of styles of satellite antennas.

LNBF disclosed in U.S. Pat. No. 6,570,524 mentioned above has no design of a waterproof cap at the opening end of a wave-guide tube thereof so that rain flows easily into the inner part of the wave-guide tube to damage the LNBF.

A cover disclosed in U.S. Pat. No. 6,191,753 shields the signal receiving face of a whole dish member and a converter assembly. The design thereof allows the converter assembly not to be exposed to the rain, but because its cover shields the signal receiving face of the dish member, it would influence the satellite signal receiving effect. Furthermore, because the volume of the cover is very large, the production cost is rather high.

Because the LNBF is an outdoor product, for preventing the LNBF from being damaged by the rain, it is usually to collocate a waterproof cap in the front of the wave-guide tube of the LNBF to maintain the normal functions and the life of the LNBF.

Because the top thickness of the waterproof cap will influence the satellite signal receiving effect, there are two methods used at the present: an O-ring is used for combining between the waterproof cap and the wave-guide tube and adhesive is used for sticking a thin film and the wave-guide tube. The common used method is the design using O-ring combination because the method using the adhesive for combing is rather time wasting.

The practice using O-ring combination is to integrate an O-ring pressing mechanism with the waterproof cap. But, because of the limitation of the present mold injection, such kind of practice will cause the thickness of the top of the waterproof cap is rather thick to influence the receiving effect of signals. If we want the thickness of the top of the waterproof cap to be thinner, a thin film must be adopted. But, because the thickness of the thin film is thinner, it cannot be integrated with the pressing mechanism. If the thin film is forced to be integrated with the O-ring pressing mechanism, deformation and shrinkage are caused because the difference of the thick and the thin parts are overlarge to lead to the waterproof effect to be in vain. Therefore, the adhesive stuck method must be used for attaining to a waterproof effect, but it also increase the needed combining time.

SUMMARY OF THE INVENTION

For improving the deficiencies of the present convention waterproof mechanism for a satellite antenna, the present invention is proposed.

The main object of the present invention is to provide a waterproof mechanism for a satellite antenna, capable of using an O-ring to cause the waterproof mechanism to be combined airtightly with the wave-guide tube, and obtaining a better satellite signal receiving effect.

Another effect of the present invention is to provide a waterproof mechanism for a satellite antenna, allowing a fixing cover and thin wall cap to be manufactured separately, the fixing cover is consequently able to have a thicker wall, and can increase the stability and the strength of the entirety after it is combined with a wave-guide tube.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention processes an improved design directed against the problems of the conventional waterproof mechanism for a satellite antenna mentioned above. Not only must a waterproof cap maintain the waterproof function on a satellite antenna, but also must the material thickness of a waterproof cap be considered to avoid influencing the satellite signal receiving effect to lead to a bad signal receiving and the decreasing and the failure of the functions of a product.

Please refer toFIGS. 1,2and3. The present invention is to separate the waterproof cap of the known technology into two parts of a fixing cover11and a thin wall cap12. The fixing cover11and the thin wall cap12are operated in coordination with an O-ring30to be combined at the upper end of a wave-guide tube21of a LNBF20to enable rain not to enter the inner portion of the wave-guide tube21, asFIG. 3shows. Another function of the thin wall cap12is used for decreasing the hindrance of satellite signals. The function of the fixing cover11or so-called rain cover is used for fixing the thin wall cap12and O-ring30on the wave-guide tube21of the LNBF20to enable the stability and the strength of the entirety to be increased to attain to the waterproof effect. The outward appearances of the fixing cover11and thin wall cap12are matched up with the one of the wave-guide tube21and can be a shape such as a circular, elliptical or square shape.

AsFIG. 3shows, the fixing cover11is formed in one body, and has a ring type first engaging portion111, second engaging portion112, in which the diameter of the second engaging portion112is larger. The second engaging portion112is connected to the lower end of the first receiving portion111. A shielding sheet113is extended upwards from the upper end of the first engaging portion111. A combining component fixedly combined with the wave-guide tube21is disposed at the lower end of the second engaging portion112, for example, at least two hooks114are disposed on the inner wall of the lower end of the second engaging portion112. The ring type sheet115is formed at the upper end of the second engaging portion112.

Please refer toFIGS. 2 and 3, the thin wall cap12is formed in one body from plastic material and has a first engaging portion121and second engaging portion124, in which the diameter of the second engaging portion124is larger. A shielding sheet122is disposed at the upper end of the first engaging portion121and the shielding portion seals a first ring type hole123of the first engaging portion111. The second engaging portion124is connected to the lower end of the first engaging portion121. The second engaging portion124has a second ring type hole125. The diameter of the second ring type hole125is larger than the first ring type hole123. A ring type sheet126is formed at the upper end of the second engaging portion.

AsFIG. 3shows, the upper end of the wave-guide tube21of the LNBF20has an engaging portion211and ring type flange212respectively corresponding to the first engaging portion121and the second engaging portion124of the thin wall cap12. Combining components corresponding to the combining components of the fixing cover11are disposed at the lower end of the wave-guide tube, for example, at least a ring type flange212corresponding to the hooks114of the fixing cover11. The hooks114can be buckled at the surfaces of the lower ends of the flange212to cause the first engaging portion121and the second engaging portion124of the thin wall cap12to be sandwiched by the fixing cover11and the wave-guide tube21.

AsFIGS. 1,2and3show, the O-ring30is put around the periphery of the first engaging portion211of the wave-guide tube21and placed at the upper side of an upper end face213of the flange212. The first engaging portion121of the thin wall cap12is engaged at the periphery of the first engaging portion211of the wave-guide tube21and the shielding sheet122seals the opening of the wave-guide tube21. The O-ring30is engaged in an area A inside the second engaging portion124of the thin wall cap12. The first engaging111of the fixing cover11is engaged at the periphery of the first engaging portion121of the thin wall cap12, the second engaging portion112is engaged at the periphery of the second engaging portion124and the ring type flange212of the thin wall cap12, and the hooks114are caused to buckle at the lower end face of the ring type flange212to allow the fixing cover11, thin wall cap12and O-ring30to be stably combined at the upper end of the wave-guide tube21.

AsFIGS. 2 and 3show, the present invention is to separate the conventional waterproof cover into two components of the fixing cover11and the thin wall cap12, and then use the O-ring30to attain to the waterproof function. Here, the shielding sheet122of the thin wall cap12is an area for satellite signals to pass through; the thickness “H” of the shielding sheet122will influence the satellite signal receiving capability of the LNBF20. Therefore, the influence of the thickness to the satellite signals must be considered to fit a customer's requirement when the thickness of the shielding sheet122is designed. The area “A” of the shielding sheet is an area for causing the O-ring30to be deformed, the value of the pressing amount must be considered to decide the size thereof when this area is planned. The thin wall cap12is then assembled onto the O-ring30after the O-ring30is assembled on the LNBF20. At this time, the O-ring30yields no deformation even if the pressing from the assembly of the thin wall cap12. But, if the fixing cover11is further assembled onto the LNBF20, the upper end of the ring sheet126of the thin wall cap12will cause the O-ring30to be deformed synchronically and sandwiched between the ring shape sheet126of the second engaging portion124of the thin wall cap12and the upper end face213of the flange212of the wave-guide tube21because the ring shape sheet115of the fixing cover11is pushed in to press. The O-ring30is caused to fill up the whole area “A” to attain to the waterproof function when the entirety of the fixing cover11is engaged with the LNBF20.

Because the waterproof cover of the known technology is to integrate the mechanism of pressing O-ring with the waterproof cover together, the thickness thereof must reach at least 8 mm and over. But, the present invention is to separate the waterproof cover of the known technology into two components of the fixing cover and the thin wall cap for pressing O-ring. The fixing can have a large thickness to press the O-ring and cause the thin wall cap and O-ring to be combined closely and stably at the upper end of the wave-guide tube, it can increase the stability and the strength of the entirety. But, it is unnecessary for the thin wall cap to have a same thickness as the fixing cover. Therefore, the thickness of the thin wall cap12can be approximately reduced to 3 mm; this can broadly increase the passing rate of the satellite signals to allow the LNBF to have a better satellite signal receiving effect.