| 摘要 |
<p>955,382. Pistons. SPERRY RAND CORPORATION. Dec. 10, 1962 [Dec. 22, 1961], No. 46506/62. Heading F2T. [Also in Divisions B4, F1 and G3] Apparatus for punching record cards includes a piston 11, loosely fitting in a cylinder 10 and having at least one circumferential groove with a side wall a exposed to the dynamic force of the fluid passing through the clearance between the piston outside dimension and the cylinder inside dimension. In operation, fluid is admitted into the cylinder at low pressure, between 5 and 35 p.s.i. through the port 16, and a portion of the fluid leaking between the piston and the cylinder at a relatively high velocity and expanding into each of the multiple grooves applies a force against each wall surface a and thus it is stated that the force with which the piston moves is multiplied, so that the point 12 pierces a record card 13 and enters an opening 14 in a die block 15. The piston may be retracted by admission of pressure fluid through an angled port 18, or by direct application of fluid through the die block to return the piston as soon as a punch hole is made. Retraction may also be effected by creating a suction force at the head of the punch cylinder as soon as the punch has been operated. The punching cycle may be controlled by a Bernoulli effect fluid amplifier.</p> |
