| 摘要 |
<p>1,004,130. Pneumatic linear-dimension gauges. CINCINNATI MILLING MACHINE CO. May 8, 1964 [Sept. 23,1963 ], No. 19356/64. Heading G1M. In order that a pressure gauge 19 should be sensitive to pressure variations due to small dimensional changes in a workpiece W but not to large ones, as the workpiece W passes beneath a work-sensing nozzle 16, the pneumatic system including the gauge 19 is provided with a valve 24 connected in parallel with a restricted passage 23 between the gauge 19 and the nozzle 16 in such a way that a diaphragm 26 within the valve responds to a pressure differential across the restriction 23 to open or close a passage through the valve 24 by-passing the restriction 23. Air under pressure is provided by a source 10 to the valve 24 and the restriction 23 connected in parallel to the gauge 19 so that the pressure changes due to a variation in air gap 18 between the nozzle 16 and workpiece W can be registered on the gauge 19. The diaphragm 26 which divides a chamber 25 within the valve 24 into two halves 25a, 25b is arranged to contact a nozzle portion 28 when the pressure in 25a is less than or equal to the pressure in 25b so that (1) a large drop occurring as the nozzle 16 senses a change from a land L to a recess R in the moving workpiece W is accompanied by a movement of the diaphragm which allows the air in the system to flow only through restriction 23 thereby providing a gradual decline of pressure reading registered on the gauge 19 and (2) a large pressure increase occurring as the nozzle 16 senses a change from recess R to land L in the moving workpiece W is accompanied by a movement of the diaphragm which allows the air in the system to flow freely through the valve thereby providing an immediate accurate reading corresponding to dimension of land L on the gauge 19. The restriction presents no resistance of movement of air for small pressure changes and therefore irregularities in the surface of land L are accurately and quickly registered on the gauge 19. In an alternative embodiment (Fig. 3, not shown) in which the valve 24 is differently arranged a nozzle 16 is supported above a pivoted lever which engages the workpiece and movements of the lever corresponding to the irregularities in the workpiece cause variations in the pressure communicated to the gauge 19.</p> |
