【正文】
ressure, the piston 170 will have been moved against spring 180 sufficiently to allow spring 154 and the high pressure fluid to close valve member 152. Valve 114 continuously operates in the foregoing manner as necessary to reduce the high pressure fluid from tank 110 and maintain in conduit 118 a desired predetermined pressure differential relative to ambient water pressure.Now, if the solenoid valve 120 is energized to an open condition, pneumatic fluid, reduced in pressure by regulator valve 114, will be admitted through port 70, groove 66, and passage 68 into the chamber 58. The reduced pressure pneumatic fluid entering chamber 58, while at lower pressure than in tank 110, is of sufficiently high pressure to cause piston 50 to move piston 20 outwardly against the ambient water pressure. When the pressure in chamber 58 acting on poppet valve 74 is sufficient to overe the force of spring 84, that valve moves away from its seat and because of its connection by rod 72 to the slide valve 64, the latter is moved to interrupt flow through inlet port 70. Since chamber 76 is maintained by the equilibrium control system 100 at a pressure substantially equal to ambient pressure, the result is a rapid or sudden drop in pressure in chamber 58, thereby allowing ambient water pressure to move pistons 20 and 50 toward the respective chambers 44 and 58.When the pressure in chamber 58 has fallen substantially to the equilibrium pressure, valve 74 closes, valve 64 opens port 70, and regulated high pressure pneumatic fluid is again admitted to the chamber 58 to act on piston 50. It will be recognized that the cycle will be repeated in an oscillatory manner at a frequency determined in part by the pressure differential between the regulated high pressure output of valve 114 and the ambient or equilibrium pressure. It will also be recognized that the stroke of the pistons 50 and 20, and hence the amplitude of the water displacement by the latter, are a function of the tension of spring 84. Accordingly, the described signal generating mechanism produces an oscillating or cyclic reciprocation o| piston 20 that produces an acoustic signal, in the surrounding water, having a frequency and amplitude that is selectable by adjustment of adjusting screws 186 and 88. The frequency of operation may be ultra low that is in the range of say 5 to 100 Hz, and yet very efficient in the use of onboard stored energy. The oscillations may be characterized as abrupt, more or less squarewaye like, and broadband. By providing suitable restrictions in flow ports 70 and 90, the oscillations may, if desired, be made more sinusoidal.Pnuematic flow exhausted through port 90 is normally pumped by the pressor 130 back into the high pressure tank 110. If a condition exists such that the pressor 130 cannot keep up with the signal generator exhaust, the surplus air will automatically be routed to the accumulator of the equilibrium control system for storage at ambient pressure. If the condition is not corrected, and a positive pressure (over ambient) develops in the accumulator, the signal generator oscillations will cease automatically, because of loss of the required differential for operation, until the pressor is able to restore the required pressure balance. Normally, the pressor will cycle on and off as necessary to keep the necessary high pressure in the tank 100, and to permit the equilibrium control system to maintain pressure equilibrium, as earlier described, relative to ambient pressures.二、英文翻譯:超低頻聲信號(hào)發(fā)生器摘 要水下超低頻聲信號(hào)發(fā)生器設(shè)計(jì)采用了氣動(dòng)驅(qū)動(dòng)信號(hào)發(fā)生的方式,并將其連接到水中接觸產(chǎn)生信號(hào)的活塞, 其中滑閥和提升閥協(xié)作產(chǎn)生壓力作用在活塞上。