Mass oscillator having an adjustable gas spring
AssigneeMTS Systems Corporation
InventorMartin M. Gram
Life of this patent
Estimating the term…
Abstract
An apparatus for oscillating a mass at a plurality of selective frequencies includes a source of compressible fluid and a cylinder having a bore filled with the compressible fluid. The cylinder includes a port opening to the bore, the port being connected to the source of compressible fluid. A piston slides in the bore to define a chamber. The piston is operably connected to the fluid mass to oscillate the mass. An average volume of the chamber is adjusted to change the frequency of the oscillating mass.
Claims27
An apparatus for oscillating a mass at a plurality of selected frequencies, the apparatus comprising:
- a source of compressible fluid at a source pressure;
- a cylinder having a bore filled with the compressible fluid and a port opening to the bore;
- a piston slidable in the bore to define a chamber, the piston reciprocating in the bore to define an average volume of the chamber, the piston being operably connected to the mass to oscillate the mass at a selected frequency, and wherein a pressure in the chamber varies during reciprocating displacement of the piston above and below the source pressure;
- and
- a valve apparatus connecting the port to the source of compressible fluid, the valve apparatus including a first check valve for adjusting the average volume of the chamber to change the frequency of the oscillating mass by allowing compressible fluid to flow into the chamber from the source to increase the average volume when the pressure of the chamber is less than the source pressure, and a second check valve for adjusting the average volume of the chamber to change the frequency of the oscillating mass by allowing compressible fluid to flow from the chamber to the source to decrease the average volume when the pressure of the chamber is greater than the source pressure.
An apparatus for generating an acoustical wave in a borehole containing a fluid mass at a plurality of selected frequencies, the apparatus comprising:
- a source of compressible fluid at a source pressure;
- a cylinder having a bore filled with the compressible fluid and a port opening to the bore;
- a piston slidable in the bore to define a chamber, the piston reciprocating in the bore at a resonant frequency to define an average volume of the chamber, the piston being operably connected to the fluid mass to oscillate the fluid mass, and wherein a pressure in the chamber varies during reciprocating displacement of the piston above and below the source pressure;
- and
- a valve apparatus connecting the port to the source of compressible fluid, the valve apparatus including a first check valve for adjusting the average volume of the chamber to change the resonant frequency of the oscillating mass by allowing compressible fluid to flow into the chamber from the source to increase the average volume when the pressure of the chamber is less than the source pressure, and a second check valve for adjusting the average volume of the chamber to change the frequency of the oscillating mass by allowing compressible fluid to flow from the chamber to the source to decrease the average volume when the pressure of the chamber is greater than the source pressure.
Dependencies are inferred from the claim text.