Torsional reed reference fluidic oscillator

Abstract

A torsional reed reference fluidic oscillator operating within 0.1% of the desired frequency over a temperature range of -65.degree. to +165.degree.F and an operating pressure of from 1 to 4 psi. The oscillator includes a torsional reed fluidic amplifier and fluidic feedback means for converting output signals from output ports of the amplifier to first and second input signals having a phase relationship for insuring operation of the apparatus as an oscillator. The amplifier is comprised of first, second and third plates, an elongated reed member, first and second torsional members and a tab, all of which are made of material having negligible thermal coefficient of expansion and negligible change in modulus of elasticity over the temperature range. The reed member is positioned within an elongated slot in the first plate, and is fixed thereto by the first and second torsional members, wherein the major axis of the torsional members is perpendicular to the plane and major axis of the reed member. The second and third plates each has a supply port, a channel fluidically coupled to the supply port, and an output port fluidically coupled to the channel. The tab, having a hole therethrough, extends from the reed member in a plane perpendicular to the major axis of the torsional members and the reed member. The tab is received within the channels in the second and third plates, and is movable between a first and second position upon corresponding movement of the reed member which is responding to the reception of the first and second fluidic input signals from the fluidic feedback means. The fluidic resonant frequency of the oscillator is approximately equal to a fixed mechanical resonant frequency of the reed member, whereby the oscillator oscillates at that mechanical resonant frequency.