CSZ EZT-570i, Техническое руководство

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EZT-570i Technical Manual
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4.7 Transfer Mechanism
Transfer mechanisms are used on thermal shock chambers (DTS/VTS/TSB) to move a basket loaded
with test product from one extreme temperature to another. These systems may utilize a single motor
drive or one or more air cylinders to move the basket between the different temperature zones.
Motor Operated Transfer Mechanism
Motor operated transfer mechanisms are typically used on TSB’s. They consist of a gear-motor drive
with a lever arm attached to the output shaft. The motor direction is switched between clockwise and
counterclockwise rotation in order to move the basket back and forth between the baths.
Limit switches are used to indicate each of the three positions, hot, cold and unload. The motor
direction is determined by the current position of the basket, as indicated by which position switch is
on, and the desired bath position set by the events. The motor runs until the limit switch for the
desired position is met.
Air Cylinder Operated Mechanism
Air operated transfer mechanisms for DTS and VTS chambers are relatively simple. A single air
cylinder is used to move the basket between the two available positions. Because of the design, the
basket provides the mechanical stop for the cylinder. The cylinder continues to push on the basket,
thus sealing the gasket surface to keep the hot and cold chambers separate. Limit switches are
positioned on each end of the cylinder in order to identify the basket position.
TSB transfer mechanisms employing air cylinders are more sophisticated. They use two cylinders,
one for up-and-down motion and the other for side-to-side motion. Limit switches are placed on each
end of both cylinders to provide position information to the EZT. In order to transfer from one bath to
the other, the basket is first raised into position. Once the basket is in the up position, the EZT then
controls the other cylinder to move the basket left or right over the opposing baths. Once the basket
is repositioned over either of the baths, it is then lowered into the bath.
4.7.1 Transfer Mechanism Failures and Corrective Actions
SYMPTOM PROBABLE CAUSES CORRECTIVE ACTIONS
Basket not transferring.
Limit switch failure.
Basket already in position.
Motor clutch slipping.
Blown fuse (motor operated).
Binding in transfer basket/mechanism.
Loss of/low air pressure.
Check limit switches. Adjust/replace.
Transfer to other position.
Check/adjust clutch tension.
Replace fuse.
Check cable tension, pulleys, cylinder
guides, etc. for wear. Adjust/repair.
Supply proper air pressure. Check
pressure regulator/adjust.
Basket not transferring to proper
position.
Limit switch failure.
Motor leads reversed.
Air lines to cylinder reversed.
Verify limit switch operation.
Swap motor leads.
Swap air lines.