Positive displacement hydraulic-drive reciprocating compressor

• US 4,761,118 A
• Filed: 02/07/1986
• Issued: 08/02/1988
• Est. Priority Date: 02/22/1985
• Status: Expired due to Fees

• Current Assignee: Franco Zanarini
• Original Assignee: Franco Zanarini
• Inventors: Zanarini, Franco
• Primary Examiner(s): Croyle, Carlton R.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/827,823
• Time in Patent Office: 907 Days
• Field of Search: 417/244, 417/261-268, 417/254, 417/255, 417/393, 417/396, 92/129, 92/85 B
• US Class Current: 417/254
• CPC Class Codes: F04B 9/1095 having two or more pumping chambers in series
• CPC Class Codes: F04B 9/115 reciprocating movement of the pumping members being obtained by two single-acting liquid motors, each acting in one direction

Abstract

The invention disclosed relates to the art field embracing positive displacement reciprocating compressors of the type featuring hydraulic drive, and sets out to simplify the construction of such units, rendering them more functional at the same time. Four coaxial bulkheads are adopted, set apart one from the next by three cylinder barrels, and three pistons which are mounted to a common rod and reciprocated thus, each in its respective barrel; the central piston and barrel are of either greater or smaller diameter than the remainder. Hydraulic oil from a power pack driving the compressor flows alternately into chambers which are occupied by the rod, and bounded at one end by one of the pistons of smaller or greater diameter.

Claims

1. A positive hydraulic-drive reciprocating compressor, comprising:

at least four coaxially-disposed bulkheads and at least three coaxial cylinder barrels located between the four bulkheads;

at least three pistons reciprocated in fluid-tight fashion each in a respective barrel, of which a central piston and relative barrel are of greater diameter and bore than the remaining outer pistons and barrels and, together with at least two relative bulkheads, create at least two low pressure chambers;

a rod interconnecting the pistons and accommodated slidably and in fluid-tight association by passages located in the central bulkheads;

flow passages communicating with power chambers, and with a hydraulic power pack driving the piston-and-rod assembly, wherein such power chambers each accommodated the piston rod and are bounded, on the one hand, by one of the outer pistons, and on the other, by a corresponding central bulkhead;

gas inlet valves which connect the low pressure chambers with a source of gas and with at least one pair of high pressure chambers, said high pressure chambers being bounded by outer ones of said barrels and corresponding ones of said outer pistons, and outlet valves which connect the one pair of high pressure chambers with at least one further pair of compression chambers, or with services to which compressed gas is to be supplied.

3. Compressor as in any of claims 2 or 1, wherein said piston and barrel diameters are chosen to correspond to a predetermined compression ratio.

8. Compressor as in any of claims 2 or 1, wherein the two outer pistons are mounted on the rod in a floating arrangement.

9. Compressor as in claim 3, wherein the floating arrangement between rod and pistons includes restrictions designed to permit a metered passage of hydraulic oil into the poer chambers.

10. Compressor as in any of claims 2 or 1, which in a double two-stage version is embodied substantially symmetrical in relation to the central position.

11. Compressor as in any of claims 2 or 1, wherein the flow passages are incorporated into the central bulkheads.

2. A positive displacement hydraulic-drive reciprocating compressor, comprising:

a plurality of coaxially disposed bulkheads, a plurality of coaxial cylinder barrels positioned between said bulkheads, at least two of said cylinder barrels defining both two power chambers and two high pressure gas chambers,

each said barrel slidably receiving pistons, a rod interconnecting said pistons, said rod passing through said bulkheads in a fluid sealed manner, at least one central low pressure chamber is defined by one said cylinder barrel and two bulkheads, said low pressure chamber slidably receiving a piston having a greater diameter than the other pistons,

at least one flow passage communicating with each power chamber, and with a hydraulic power pack driving said pistons and rod, said flow passages disposed symmetrically with respect to said central low pressure chamber, gas inlet valves connecting the central low pressure chamber with a source of gas and at least with said two high pressure chambers, outlet valves connecting said two high pressure chambers with at least two compressing chambers and with a consumer of a compressed fluid.

4. A compressor according to claim 2 having an even number of said bulkheads.

5. A compressor according to claim 4 having four said bulkheads.

6. A compressor according to claim 2 having odd number of said cylinder barrels.

7. A compressor according to claim 6 having at least three said cylinder barrels.

12. A positive hydraulic-drive reciprocating compressor, comprising:

at least four coaxially-disposed bulkheads and at least three coaxial cylinder barrels located between the four bulkheads;

at least three pistons reciprocated in fluid-tight fashion each in a respective barrel, of which a central piston and relative barrel are of lesser diameter and bore than the remaining outer pistons and barrels and, together with at least two relative bulkheads, create at least two low pressure chambers;

a rod interconnecting the pistons and accomodated slidably and in fluid-tight association by passages located in the central bulkheads;

flow passages communicating with power chambers, and with a hydraulic power pack driving the piston-and-rod assembly, wherein such power chambers each accomodate the piston rod and are bounded, on the one hand, by one of the outer pistons, and on the other, by a corresponding central bulkhead;

gas inlet valves which connect the low pressure chambers with a source of gas and with at least one pair of high pressure chambers, and outlet valves which connect the one pair of high pressure chambers with at least one further pair of compression chambers, or with services to which compressed gas is to be supplied.