Washer Banging in the Spin and Walking Across the Floor? NL-WSP-4 Suspension Rod Stiffness and Damping Bench, Six Stations (washing machine test equipment)

Washers that bang in the spin cycle, walk across the floor and sometimes stop dead when the tub hits the cabinet; new damper parts help for a while, then it comes back a few months later. The suspension rods — spring plus damper tube — carry the whole weight and swing of the tub, and after thousands of spins the springs fatigue and the grease is pumped out of the damper tubes; once the four no longer match, the tub orbits off-centre and the banging, the noise and the displacement alarms follow. Vibration testing on the line usually runs a few cycles at rated load, so what stiffness is left after hundreds of hours and thousands of spins is unknown before shipment — and by the time the household complains, it is usually a whole batch.

What the NL-WSP-4 suspension rod bench measures

• Six stations, each with independent loading and temperature control, running single rods or a set of four at their installed angles (the suspension and damping branch of our washing machine test equipment)
• Stiffness curve: stepped loading over 0-2000N giving a force-displacement curve and stiffness value, showing whether the spring has entered its non-linear range
• Damping force against velocity: damper force at several speeds, showing whether the grease still controls the swing
• Spin-duty cycling: set amplitude, frequency and load to reproduce the spin swing over tens of thousands of cycles
• Four-rod matching: stiffness and damping spread across a matched set, quantifying the off-centre orbit risk
• Resonance sweep: a frequency sweep locating the tub system’s natural frequency so the working speed range can be kept clear of it
• Temperature, humidity and detergent duty: cycling at set conditions to bring out creep in the spring coating and plastic parts
• Barcode and batch binding, with raw data exported per unit for spring and damper lot comparison

Applicable standards

GB 4706.1 (household appliances – general safety), GB 4706.24 (washing machines – particular requirements), GB/T 4288 (electric washing machines for household and similar use), IEC 60335-2-7 (washing machines – particular requirements) and GB/T 2828 sampling; criteria can follow the customer’s standard and the rod construction.

Stations and throughput

Six stations running continuously turn a spin listened to by ear and a rod pressed by hand into stiffness, damping force and four-rod spread data, with decay rechecked round by round — so incoming rods, assembly and end-of-line units can all be sampled batch by batch, stopping banging, walking and noise before shipment.

Manufacturer

Guangdong Endurance Electronic Equipment Co., Ltd. — a non-standard testing equipment manufacturer of suspension rod stiffness and damping benches, washing machine test equipment, dishwasher test equipment, pump test bench and pump performance test systems and level sensor life test machines.

Keywords: pump test bench, pump performance test, level sensor life test, dishwasher test equipment, washing machine test equipment.