PLANT FOR ASSEMBLING WASHING MACHINE PUMPS
Electric motor and pump for the Washing Machine Whitegoods industry.
Components per model
Pallet transfer line, with pallets in waiting, 5 automatic assembly stations, 4 manual assembly stations, 3 automatic testing stations.
The product is transported along a friction drag roller chain aboard a set of 30 off encoded pallets. The first operator places on the pallet the bottom motor case and rotor. After transfering stations, the pallet arrives at the second operator, who mounts the top motor case. At the first automatic station into the two halves of the motor case are automatically fed four screws which are then tightened with a control of the correct torque being achieved. The following station performs an automatic electrical test. Any rejects from this test are diverted to a manual repair station which has a display reporting the reason for rejection during the previous automatic-electrical test. At the next automatic assembly station a spacer is placed onto the motor shaft. A third operator then mounts the capacitor onto the pallet. At the next automatic station a pick and place gripper raises the capacitor into position and another gripper grabs a nut and fixes the capacitor in position, again controling that the correct torque has been achieved. At the next manual station the pump body and pump rotor assembly are placed onto the motor, and then the pump rotor is screw fitted the the motor shaft again with insertion depth and torque control. A torque transducer is used to ensure that the torque is delicately retained within the allowable range, to avoid the possible breakage of the plastic rotor if overtightened. At the next automatic station three self tapping screws are inserted to fix the pump body to the motor. The assembled pump is then transfered to the leakage test station. The leakage test is performed under air pressure noting minute pressure drops with sensitive pressue transducers. The next automatic test station checks for motor pump NVH under dry running conditions. A central PLC controls the overall machine function and pallet encoded information, however the automatic stations have their own PLC or PC to more efficiently operate the intricate automatic functions.