Modified rotary compressor yielding sinusoidal pressure wave outputs

DETAILED DESCRIPTION I claim: 1.
In a rotary compressor device in which substantially trochoidal curves form the inner surface of the working chambers and the configuration of the internally placed rotary piston of said device and wherein side surfaces close the device to complete the working chambers, the improvement comprising: a volume formed along a flank of said rotary piston in communication with the compression volume under said flank and adjacent a side surface; passageway means associated with said side surface for constantly communicating with said volume as said rotary piston revolves; and porting means communicating with said passageway means for providing an outlet for sinusoidally varying pressure generated by said device.
2.
The device according to claim 1 wherein the trochoidal curves are selected from the group of curves consisting of the peritrochoid, epitrochoid, and hypotrochoid.
3.
The device according to claim 2 wherein the passageway means are within a boundary prescribed by the inner envelope of the rotor revolving according to the trochoidal curve utilized.
4.
The device according to claim 3 wherein means for shorting the regions under the unused rotor flanks to a common volume are provided to reduce power consumption by the device.
5.
The device according to claim 4 wherein said common volume comprises the crankcase region of the device and wherein the shorting means comprise passage means from the unused rotor flanks to said crankcase region.
6.
The device according to claim 5 further comprising further passage means directly connecting the unused flanks.




Description:
BACKGROUND OF THE INVENTION The invention relates to the field of rotary compressors.
In particular it encompasses a modification to such a compressor of the type particularly useful in the area of cryogenic coolers, such as the one found in U.
S.
Pat.
No.
3,853,437 which is incorporated by reference, which, for maximum efficiency, requires a square or sinusoidal pressure wave.
The standard piston-type compressor, while providing a sinusoidal output pressure, has inherent limitations to efficiency because a rotary-to-linear motion conversion is necessary