| 摘要 |
<p>1,187,287. Fluid switch. TEXTRON Inc. 14 Aug., 1967 [27 Sept., 1966], No. 37244/67. Heading G4P. [Also in Division G3] A proportional amplifier, Figs. 1, 3A, 3B, 3C (also Figs. 2A, 2B, not shown) is characterized in that it uses lamina flow, this being achieved by a relatively long inlet channel 20 which progressively tapers, see Fig. 3C, in a vertical plane, from just beyond the interaction region 30 up to the output channel, and also in that the control signal is arranged to produce a static pressure which acts along a length of the power jet longer than its width. In operation, with no control signal the main jet flows direct to the main outlet (Fig. 3A). With an increasing control signal the main jet is progressively displaced towards a side vent 43, until, with a sufficiently large control signal, the main jet flows entirely into the vent (Fig. 3B). The control pressure/input pressure characteristic (Fig. 4, not shown) for the arrangement displays a significant linear portion. A modification with an off-centre outlet is described (Fig. 7, not shown). A switch having a characteristic (Fig. 6, not shown) with no significant linear portion, is produced by coupling the two vents 42, 43 of the proportional amplifier shown in Fig. 1. The main jet then flows either direct to the main outlet, Fig. 5A, or to the vented loop, Fig. 5B, and it is substantially impossible to divide the main jet between the main outlet and the vented loop because once flow commences in the loop it exerts positive feed-back and causes rapid switching.</p> |
