1. Field of the Invention
The present invention relates to an opaque container fluid indicator and, more particularly, to a simple structure of opaque container fluid indicator that is inexpensive to manufacture and, that accurately indicates the presence/non-presence condition of fluid in the opaque container.
2. Description of the Related Art
When using an opaque fluid container to hold a fluid, for example, an oil tank to hold hydraulic fluid or greasing oil, or a water tank to hold cooling water, a fluid indicator may be used to indicate the presence of fluid. There are known two fluid indicators for this purpose. According to the design shown in FIG. 1A, an opening is made on the peripheral wall of the opaque fluid container 1, and a panel 2 is fixedly fastened to the opening of the opaque fluid container 1. The panel 2 has a transparent view window 3 through which the level of fluid W in the opaque fluid container 1 is viewed. This design has numerous drawbacks including (1) making an opening on the peripheral wall of the opaque fluid container 1 obstructs the unity and structural strength of the opaque fluid container 1; (2) installation of the panel 2 in the opening of the peripheral wall of the opaque fluid container 1 is complicated; (3) an accidental impact of the opaque fluid container 1 may damage the connection between the peripheral wall of the opaque fluid container 1 and the panel 2, thereby causing a leakage. According to the design shown in FIG. 1B, a track 5 is installed in the opaque fluid container 4, an extension tube 6 is upwardly extended from the track 5, a float 7 is floating in fluid W and moved along the track 5, and a buoy 8 supported on the float 7 and moved with the float 7 up and down in the extension tube 6 subject to the level of fluid W in the opaque fluid container 4. This design is still not satisfactory in function because of the following drawbacks: (1) this design of fluid indicator is expensive to manufacture because it comprises too many parts; (2) the extension tube 6 tends to be damaged because it protrudes over the top side of the opaque fluid container 4 at a certain distance; (3) the float 7 tends to be jammed in the track 5 due to accumulation of oil dust, resulting in an error indication; and (4).
The present invention has been accomplished to provide an opaque container fluid indicator, which eliminates the aforesaid drawbacks. It is one object of the present invention to provide an opaque container fluid indictor, which is inexpensive to manufacture. It is another object of the present invention to provide an opaque container fluid indicator, which is easy to install. It is still another object of the present invention to provide an opaque container fluid indicator, which fits any of a variety of opaque fluid containers without making any structural change of the opaque fluid container. To achieve these and other objects of the present invention, the opaque container fluid indictor comprises a mount fixedly fastened to the spout of the opaque fluid container, a transparent hand pump supported on the mount, and two suction tubes downwardly extended from the hand pump and suspended in the opaque fluid container. The hand pump is formed of an elastic transparent bladder and a bladder holder. After installation in the spout of the opaque fluid container, the hand pump is operated to suck in fluid from the opaque fluid container. When the fluid level dropped below the critical elevation, air passes to the inside of the hand pump to force fluid out of the hand pump. Therefore, the hand pump is filled up with fluid when the fluid level is high; the hand pump is empty when the fluid level is low.