Class 417/261 - Serial interstage distributors in piston

Subclass of Class 417 - Pumps
Definition: Apparatus in which the piston is provided with a plurality
No. of patents: 4
Last issue date: 08/14/2007

Number	Title	Issue Date
7255071	Supercharged two-stroke engine with upper piston extensions An apparatus useful in a two-stroke cycle engine or in a pump as a piston disposed within a piston cylinder. The piston cylinder has an intermediate piston cylinder head disposed transversely across the interior of the piston cylinder. The piston has at least one up...	08/14/2007
7140846	Vacuum pump having main and sub pumps A vacuum pump having a rotary shaft that is rotated by a drive source has a main pump and a sub pump. The main pump includes a pump chamber and a gas transferring body that is located in the pump chamber. The main pump is driven by the drive source through the rotar...	11/28/2006
6966283	Apparatus with piston having upper piston extensions An apparatus useful in a two-stroke cycle engine or in a pump as a piston disposed within a piston cylinder. The piston cylinder has an intermediate piston cylinder head disposed transversely across the interior of the piston cylinder. The piston has a lower portion...	11/22/2005
5209647	Straight cylinder gas compressor with a reduced diameter compression chamber A straight cylinder, clamped between end headers, confines valve assemblies wholly therewithin, and has a cylindrical sleeve set within one half length of the cylinder to effect a staging, i.e., a two-step compression, of the admitted gas....	05/11/1993

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