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眼鏡架鼻梁邊緣抗彎變形測試儀

鼻梁變形測試儀

測試原因：測定鏡架具有一定的鏡片保留能力，保證鏡架可安全佩戴2年或以上,，防止鏡片因輕微的沖擊而脫落或扭擰而變形,，影響佩戴效果。

參考標準：EN1836：2005,、ISO12870：2004,、GB/T14214：2019等等

技術(shù)參數(shù)：

1、環(huán)形夾具直徑：25mm±2mm

2,、加壓桿直徑：10mm±1mm

3,、運行裝置：電動+氣動

4,、壓力值：5N

5、持壓時間：5s

6,、計時裝置：電子顯示自動計時

測試方法及標準：

1.確定左右鏡片幾何中心點,，并計算兩中心點距離C（參考標準：ISO8624）；

2.在鏡片中心點2mm范圍內(nèi)夾住鏡片,，并使未夾鏡片保持水平狀態(tài),；

3.調(diào)整下降壓桿，使其落點剛好處于中心點2mm范圍內(nèi),，記下此值為初始值,；

4.設(shè)定壓力為5N，啟動儀器,，使位移相當于兩鏡片幾何中心距C的10,，保持5秒；

5.將壓桿回復(fù)原位,，放松20秒

6.檢查鏡架是否有裂縫,，并測定鼻梁變形百分比（變形量不超過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.

眼鏡架鼻梁邊緣抗彎變形測試儀

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