Microwave door loose after a year of use? A servo door cycle tester with the 89N closing force scale for compliance testing

Model: NL-KGM

The problem

The door of a microwave oven, oven or toaster is opened dozens of times a day: hinges go slack, hooks stop closing cleanly, the door sags, and the internal wiring flexed by every opening eventually breaks inside its sleeve. GB 4706.1 and IEC 60335 set explicit clauses for door durability and interlock performance, but manual testing cannot count cycles consistently, cannot control the closing force and cannot monitor the live electrical state at the same time, so such reports rarely survive an audit.

Capability

A servo motor drives the gripping arm about the door axis through any opening angle up to 180 degrees, both set on the touch screen. Opening speed runs from 0 to 10 cycles per minute with opening and closing speeds set separately to mimic real use. Pneumatic fingers grip the door like a hand with no lateral thrust, so the door is not pushed off its hinges. The arm carries a torque sensor that controls the closing force, and the panel carries the 89N closing-force scale required by the UL test. The machine switches the sample power on automatically and digital ammeter and voltmeter meters watch the current and supply state throughout the cycle - wiring fatigue and interlock faults show up as current anomalies. Four fault conditions are judged automatically: supply failure, current fault, door failed to open and door failed to close, with over-current, earth-leakage and over-temperature protection backing the circuit. The sample is clamped top and bottom so it cannot swing or shift; sample height goes up to 1600mm inside a W850xD800xH800mm enclosure. Aluminium sleeve fixtures with pins and quick straps cover samples of 300-700mm and weigh about 15 kg, so model changes are quick.

Key specifications

• Application: door hinge open-close endurance for small kitchen appliances
• Opening angle: 0-180 degrees, set on touch screen
• Cycle speed: 0-10 per minute, opening and closing set separately
• Gripping: pneumatic fingers simulating a hand, no lateral thrust
• Door type: right-hand flat door (left-hand on request)
• Drive: servo motor rotating about the door axis
• Closing force: torque sensor with 89N scale for UL testing
• Live monitoring: digital ammeter and voltmeter, sample powered automatically
• Fault judgement: supply fault, current fault, door not open, door not closed
• Protection: over-current, earth leakage, over temperature
• Sample range: height up to 1600mm, fixtures for 300-700mm doors
• Internal space: W850xD800xH800mm; outline 1000x800x1600mm

Applications

Door durability and interlock verification at microwave, oven and toaster plants; incoming and finished-goods life sampling for small appliance brands; GB 4706.1 and IEC 60335 door endurance testing at safety and reliability laboratories; hinge and hook supplier qualification

About the manufacturer

Guangdong Endurance Electronic Equipment Co., Ltd provides non-standard customization, drawing confirmation, factory acceptance, on-site installation and commissioning, operation training and long-term technical service; 12-month warranty and long-term spare parts supply. Tel: 0760-88500902 / 13416787649. Web: en.zsnaili.com.