Apparatus for detecting level changes in distance

An apparatus useful in detecting changes in the amount of liquid in a liquid storage tank comprising:

• a. signal emitting means capable of emitting a substantially constant signal;
• b. support means associated with said signal emitting means and acting to hold said signal emitting means substantially stationary;
• c. signal reflecting means associated with support means, said signal reflecting means being located at least partially within a float means which is connected to said support means, said float means being located at least partially in said liquid, said signal reflecting means reflecting at least a portion of said substantially constant signal from said signal emitting means to produce a reflected signal, said signal reflecting means being movably secured to said support means and being moveable in a substantially straight line direction toward or away from said signal emitting means in response to changes in the amount of liquid in said storage tank;
• and
• d. signal receiving means capable of receiving a portion of said reflected signal from said signal reflecting means, said signal receiving means being substantially stationary with respect to said signal emitting means, whereby a change in said signal received by said signal receiving means is indicative of a change in the amount of liquid in said storage tank.