| 摘要 |
1,204,010. Fluid analog systems. GENERAL ELECTRIC CO. May 20, 1968 [May 29, 1967], No.23869/68. Heading G3H. [Also in Division G1] An open-loop fluidic analog-type accelerometer without any close-fitting, sliding-motion parts comprises an inertial mass 16 resiliently mounted for sensing a selected component of acceleration and generating from a steady pressurized fluid signal a differential analog-type pressurized fluid signal proportional to the acceleration and a communicating analog-type fluid amplifier for amplifying the signal. A sensor 10, Fig. 1, for sensing acceleration in a direction 19 of a body by which it is carried, comprises a frame 18 supporting an end 12 of a resiliently flexible member 11 carrying an inertial mass 16 at its other end 13. Pressurized fluid from a source Ps is supplied through a central passage 14 to issue as a jet from a nozzle 15 at the end 13. A part 20 of the frame 18 contains two fluid receivers 21, 22 equispaced about a null position of the mass 16 in a line parallel to the direction 19. For small displacement of the mass 16 due to acceleration there is a linear relationship between the acceleration and displacement. The differential pressure signal sensed by the recievers 21, 22 is amplified by one or more stages of analogtype fluid amplifiers 27 Fig. 2 after filtering by a fluid resistor R and capacitor C for compressible fluids or an inductor-resistor circuit for incompressible fluids. To constrain the mass 16 to movement only in the required direction 19 the member 11 is formed with fins 17 or the passage 14 is given a crosssection elongated transversely in the direction 19. The receivers 21, 22 may be rectangular and a centre vent passage may be provided. To sense the components of an acceleration in two mutually perpendicular directions, two degrees of freedom of movement are allowed and two pairs of receivers are provided connected to two amplifying systems, Fig.3a (not shown) and alternative arrangements of the receivers are described with reference to Figs. 3b and 3c (not shown). A sensor for angular acceleration comprises a cylindrical mass 16 for rotation about its axis by two torsionally resilient members 40, 41. One member 41 Fig.4a (not shown) may be hollow and communicate with a partly axial, partly radial passage from which a jet issues when the member 41 receives pressurized fluid to be received and amplified as for linear acceleration. Alternatively the mass 16 may carry a vane 49, Fig.4b projecting between two nozzles 54, 55 which receive fluid under pressure through flow restrictors 53. The back pressures developed in passages 23, 24, when angular acceleration occurs are amplified and their difference is proportional to the angular acceleration. The accelerometer may be used to sense single or double axis linear vibrations or torsional vibrations by monitoring a central vent symmetrically placed with respect to the other receivers e.g. 21, 22. |
