| 摘要 |
<p>1, 096, 169. Hardness tests. ERNST LEITZ G.m.b.H. Nov.30, 1965 [Feb.23, 1965], No. 50724/65. Heading G1S. A hardness testing device comprises a pump 30 driven by an electric motor 31 and arranged to discharge fluid into a pressure chamber 16 communicating through a duct 15 with a pressure response actuating device 2 for an indenter 1, the pressure chamber 16 having a flexible wall 17, a weight 24 for loading the wall 17 and a switch 21 responsive to the deflection of the wall operable to control energization of the motor 31. The indenter 1 is retained in the rest position by a permanent magnet 9. In use pressure is revised in chambers 3, 16 to exert a pressure on the indenter 1 by saving the weight 24 to close switch 21' and closing valve 29 to produce a pressure in pump 30. After testing the valve 29 is opened to effect return of the indenter 1.</p> |
