摘要:
A dial indicator for use on apparatus for measuring Rockwell hardness and ovality or out-of-roundness. A sensing spindle is biased axially and movable axially in opposite directions in response to variations in a surface being sensed. The spindle comprises a rack driving a pinion during axial travel thereof for driving an auxiliary pointer with which the reference axial position of the sensing spindle is established. A magnification gear is coupled to the pinion through a slip clutch coupling a main pointer to the sensing spindle. The sensing spindle is stopped by a stop cooperative with the magnification gear to establish a reference position from which indications are made. The reference position of the sensing spindle is a position from which indicated sensing of the sensing spindle is initiated. The use of the auxiliary pointer results in a precise reference condition being established for the dial indicator.
摘要:
An electron gun for use in electron irradiation equipment. The gun comprises a cartridge including a Wehnelt electrode and a filament with two plug electrodes mounted on an insulating plate. The filament is mounted between the Wehnelt electrode and a conductive plate by two fasteners and can be adjustably aligned with respect to the Wehnelt electrode by moving the electrode with respect to the filament before the mounting is made fast. The electrical potential supply terminal has two jacks which receive the plug electrodes thereby mechanically and electrically coupling the cartridge to the potential supply and the Wehnelt electrode receives its potential through a resilient contact on the potential supply terminal.
摘要:
An apparatus for measuring hardness of a specimen comprises indenting means for forming an indentation in the upper surface of the specimen, loading means for applying a predetermined load onto said indenting means and an optical system for measuring said formed indentation which is a measure of the hardness of the tested specimen. The loading means is mechanically disconnected from the indenting means and adapted to be engaged with the latter, only when the load is applied thereto upon the measurement. By such arrangement, the rigidity, mass as well as bulk of the supporting structure for the indenting means can be considerably reduced, and hence a dynamical load due to such factors which may constitute a source of error in the measurement can be effectively eliminated.