Glasses frame nose bridge edge bending deformation tester

Glasses frame nose bridge edge bending deformation tester

Nose bridge deformation tester

Test reason: It was determined that the frame has a certain degree of lens retention ability, ensuring that the frame can be safely worn for 2 years or more, preventing the lens from falling off or deforming due to slight impact, and affecting the wearing effect.

Reference standards: EN1836:2005, ISO12870:2004, GB/T14214:2019, etc

Technical parameters:

1. Ring clamp diameter: 25mm ± 2mm

2. Pressure rod diameter: 10mm ± 1mm

3. Operating device: electric+pneumatic

4. Pressure value: 5N

5. Holding time: 5s

6. Timing device: electronic display automatic timing

Testing methods and standards:

1. Determine the geometric center points of the left and right lenses, and calculate the distance C between the two center points (reference standard: ISO8624);

2. Clamp the lens within a 2mm range from the center point of the lens and keep the unclamped lens horizontal;

3. Adjust the descent pressure rod so that its landing point is exactly within 2mm of the center point, and record this value as the initial value;

4. Set the pressure to 5N, start the instrument so that the displacement is equivalent to 10 times the geometric center distance C between the two lenses, and hold for 5 seconds;

5. Return the pressure rod to its original position and relax for 20 seconds

6. Check for cracks in the frame and determine the percentage of deformation of the nose bridge (deformation not exceeding 2).

Edge Transverse Test

Frames to be tested shall be propery glazed. For purposes of unifomity, 6base,2-mm 0.08-in) nominal-centr thickness, V-beveled plano power glass is recommended. The right eyewire of the frame to be tested shal be clamped fimly in the vertical position as wom,with the left eyewire unsupported. A spring balance shall be used to apply a downward force of22.24 Newtons(5-bf) to the endpiece area of the left eye. Pressure shall be released immediately after reaching the 22.24-Newton (5-bf)level. Upon removal of theload, no deformation shal be apparent in the frame.

Glasses frame nose bridge edge bending deformation tester

Flat Transverse Test

Frames to be tested shall be properly glazed. For purposes of uniformity,6-base,2-mm (0.08-in) nominal-center thickness, V-beveled plano power glassisrecommended. The frame to be tested shall be laid on afirm, level supportwith the front lens surface downward so that one eye and one-half of the bridge project beyond the edge of the support. The frame shall be clamped frmly in position. A spring balance shall be used to apply a downward force of 4.45 Newtons(1-lbf)to the projecting endpiece area of the frame. Pressure shall be released immediately afterreaching the 4.45-Newton (1-Ibf)level. Upon removal of the load, no deformation shall be apparent in the frame