Single-step or muti-step piston compressor

Abstract

The invention relates to a novel piston compressor whose return valves have a very good closure force and are extremely tight. The inlet return valve ( 15 ) is provided with a first sealing membrane ( 17 ) and the outlet return valve ( 30 ) is provided with a third sealing membrane. The two sealing membranes ( 17,32 ) are produced from an elastic polymer which has high disruptive strength, high temperature compatibility and memory properties.

1 . Multistage piston compressor comprising a valve casing ( 4 ) and a shiftable valve piston ( 9 ) formed as a single piece and driven linearly oscillating by a drive motor ( 2 ), wherein 
 the multistage piston compressor is furnished with at least one volume changeable low-pressure chamber ( 5 ) with an intake check valve ( 15 ) and with at least one volume changeable high-pressure chamber ( 6 ) with a discharge check valve ( 30 ), wherein the valve piston ( 9 ) includes a low-pressure piston ( 10 ) and the high-pressure piston ( 11 ) and wherein the low-pressure chamber ( 5 ) and the high-pressure chamber ( 6 ) are connected to each other through an overflow duct ( 19 ), wherein an overflow check valve ( 20 ) opening in the direction toward the high-pressure chamber ( 6 ) is inserted in the overflow duct ( 19 ),    characterized in that    the intake check valve ( 15 ) is equipped with an intake sealing membrane ( 17 ) and wherein the discharge check valve ( 30 ) is equipped with a discharge sealing membrane ( 32 ) and wherein the two sealing membranes ( 17 , 32 ) comprise an elastic polymer with a high rupture strength, with a high compatibility to temperature and with memory properties.    
   
   
       2 . Multistage piston compressor according to  claim 1 , wherein the intake check valve ( 15 ) is equipped with several intake openings ( 16 ) disposed on a partial circle, 
 characterized in that    the intake sealing membrane ( 17 ) of the intake check valve ( 15 ) is fitted into a sunk bore hole of the valve case floor ( 7 ) with a ball shaped or angular bore hole base and wherein the first sealing membrane ( 17 ) is fixed under tension by a centrally placed and mushroom shaped attachment element ( 18 ), wherein the attachment element ( 18 ) immerses only to such an extent into the sunk bore hole that the attachment element ( 18 ) closes flush with the inner face of the valve case floor ( 7 ) and wherein the intake sealing membrane ( 17 ) is only pretensioned by the attachment element ( 18 ) to such an extent that the sealing membrane ( 17 ) still remains rotatable.    
   
   
       3 . Multistage piston compressor according to  claim 1  wherein the discharge check valve ( 30 ) is furnished with several outlet openings ( 33 ) disposed on a common part circle, 
 characterized in that the discharge openings ( 33 ) are entered into a valve plate ( 31 ), wherein the valve plate ( 31 ) is tensioned between the valve casing ( 4 ) and a valve casing cover ( 8 ) and wherein the discharge sealing membrane ( 32 ) is formed as a ring and is held with the outer circumference of the discharge sealing membrane ( 32 ) without tension between the valve plate ( 31 ) and the valve casing cover ( 8 ), wherein the third sealing membrane ( 32 ) with its inner circumference covers over the outlet openings ( 33 ).    
   
   
       4 . Multistage piston compressor according to  claim 3 , wherein the overflow check valve ( 20 ) is equipped with a sealing disk, 
 characterized in that    the overflow duct ( 19 ) joins at least two passage bore holes ( 26 ,  27 ) and wherein the sealing disk of the overflow check valve ( 20 ) is formed as a loosely guided and stroke limited overflow sealing membrane ( 28 ), wherein the passage bore holes ( 26 ,  27 ) of the overflow duct ( 19 ) exhibit different diameters and wherein the passage bore holes ( 26 ,  27 ) are disposed on a common part circle with a radial distance to the axis of the overflow sealing membrane ( 28 ) and wherein the passage bore holes ( 26 ,  27 ) are completely covered by the overflow sealing membrane ( 28 ).    
   
   
       5 . Multistage piston compressor according to  claim 4 , 
 characterized in that    the overflow sealing membrane ( 28 ) comprises an elastic polymer with a high rupture strength, with a high compatibility to temperature and with memory properties.    
   
   
       6 . Multi-stage piston compressor according to  claim 5 , 
 characterized in that    the overflow sealing membrane ( 28 ) is fitted into a recess ( 24 ) of a valve support ( 23 ) and wherein the sealing membrane ( 28 ) is covered by a stop grid ( 29 ).    
   
   
       7 . Multistage piston compressor according to  claim 6 , 
 characterized in that    the two passage bore holes ( 26 ,  27 ) are entered with the different diameters into the cylindrical recess ( 24 ) of the valve support ( 23 ) and have connection to the overflow duct ( 19 ), wherein the overflow duct ( 19 ) is formed as a kidney shaped chamber ( 21 ) in the joining region.