TCS 682-15, Руководство по обслуживанию, Страница: 3 / 24

682 METER OPERATION
The 682 meter is a true Positive Displacement Meter, with the inlet and outlet on the same
horizontal plain (straight in - straight out). Within the meter, three plungers are fitted within
their respective cylindrical measuring chambers. The plungers are joined to a wobble plate,
which has a shaft extending from its upper surface. The wobble plate also has a valve pivot
attached beneath it. The valve pivot drives a sliding valve from piston to piston as product
flows, controlling the sequence of events.
The wobble plate shaft is always held at an inclined position by the center gear post, and the
wobble plate itself is prevented from rotating by four guide pins on the pivot bracket assembly.
As product enters the meter, it initially flows into the upper housing. The sliding valve will now
be in position to open one measuring cylinder. The plunger for that particular cylinder will be at
the upper position. With the pressure below it relieved, and an upper housing full of product, the
pressure on top of that plunger will cause it to move toward the bottom of the cylinder, thus
forcing out the remaining product. As this occurs, another plunger will be forced from the down
position to the upper position. The sliding valve moves via the wobble plate to open the inlet of
this cylinder. As the plunger moves upward, it draws product into the measuring cylinder from
the bottom. Once this plunger reaches the upper position, and the cycle will repeat, so long as
product continues to enter the meter. If product flow stops, pressure in the meter equalizes and
motion stops. Thus the meter only operates when product is flowing.