| 摘要 |
<p>930,939. Bourdon gauges. MANNING, MAXWELL & MOORE Inc. May 18, 1961 [May 19, 1960], No. 18149/61. Class 106 (2). A Bourdon-tube system for measuring a small range in the total pressure variation, comprises an input Bourdon tube S1 the tip 34 of which is constrained against deflection by a spring 38 of a material, such as the alloy " Ni-Span C " (Trade Mark), having substantially temperature - invariant elasticity modulus, until the desired pressure range is reached, whereupon deflection of the tube S1 will raise, or lower, the wheel 42, thus pivoting a semi-circularly-shaped, spring-loaded " flapper " valve F, pivoted near the straight edge at 31, 32, to vary its distance from an air-nozzle 27 supplied by a constant pressure source through inlet 45. R is a diaphragm-valve system, and variations in the back pressure at nozzle 27 are applied, via the air-tube 28 (this is supported on, but separate from, a second Bourdon tube S2 to be referred to presently), to a diaphragm 47 (Fig. 6) to move the valve member 58a, thus causing variation of pressure in a tube U leading to a pressure-gauge G, recording device D, or a pressure switch S. Pressure in the tube U is also applied, via channel 25a, to a feed-back Bourdon tube S2 the tip deflection of which is such as to move the nozzle 27 the correct amount to maintain linearity of the back pressure variation with the input pressure variation. The separation between nozzle 27 and the flapper valve F may be varied by rotation of the latter about a vertical axis.</p> |
