Apparatus and Method For Compressing a Gas

Abstract

An apparatus and method for compressing a gas is disclosed. A compressor, in particular a piston compressor, has a low pressure stage for compressing the medium from an inlet pressure to an intermediate pressure, and has a high pressure stage for compressing the medium from the intermediate pressure to a high pressure. A compensating volume with an adjustable dead volume is connected upstream of the high pressure stage.

1 - 15 . (canceled) 
   
   
       16 . A compressor, in particular a piston compressor, for compressing a gaseous medium, having a low pressure stage for compressing the medium from an inlet pressure to an intermediate pressure, and having a high pressure stage for compressing the medium from the intermediate pressure to a high pressure, wherein a compensating volume with an adjustable dead volume is connected upstream of the high pressure stage. 
   
   
       17 . The compressor according to  claim 16 , wherein the dead volume formed by the compensating volume is adjustable as a function of the inlet pressure. 
   
   
       18 . The compressor according to  claim 17 , wherein the compensating volume is set at a minimum dead volume with maximum inlet pressure and with decreasing inlet pressure is adjustable in a direction of a maximum dead volume. 
   
   
       19 . The compressor according to  claim 16 , wherein the compensating volume is embodied as a compensating cylinder featuring a cylinder that is displaceable in a housing. 
   
   
       20 . The compressor according to  claim 19 , wherein the cylinder is provided with a first control surface as a stepped piston, which is arranged in the compensating volume and is acted upon by the intermediate pressure, and features a second control surface on an upper end which is acted upon by the inlet pressure. 
   
   
       21 . The compressor according to  claim 16 , wherein the compensating volume is provided with a cooling device. 
   
   
       22 . The compressor according to  claim 21 , wherein the cooling device is formed by cooling fins arranged on a housing of the compensating volume. 
   
   
       23 . The compressor according to  claim 16 , wherein the compressor features a piston that is longitudinally displaceable in a housing and which is driveable hydraulically. 
   
   
       24 . The compressor according to  claim 16 , wherein the low pressure stage has a first pressure chamber and a second pressure chamber. 
   
   
       25 . The compressor according to  claim 16 , wherein the high pressure stage has a first pressure chamber and a second pressure chamber. 
   
   
       26 . The compressor according to  claim 16 , wherein external cooling is provided on a housing of the compressor. 
   
   
       27 . The compressor according to  claim 23 , wherein internal cooling is provided on the piston. 
   
   
       28 . The compressor according to  claim 23 , wherein the piston is provided with at least one longitudinal borehole which is connected to a drive pressure chamber. 
   
   
       29 . The compressor according to  claim 25 , wherein a compensating volume is allocated to each pressure chamber of the high pressure stage. 
   
   
       30 . Use of a compressor according to  claim 16  for compressing hydrogen, in particular in a hydrogen filling station. 
   
   
       31 . A compressor, comprising:
 a low pressure stage;   a high pressure stage coupled to the low pressure stage;   a piston moveably disposed within the low pressure stage and the high pressure stage; and   a cylinder defining an adjustable gas volume coupled to the high pressure stage, wherein the gas volume of the cylinder is providable to the high pressure stage.   
   
   
       32 . The compressor according to  claim 31 , wherein the gas volume is adjustable by an inlet pressure to the low pressure stage. 
   
   
       33 . The compressor according to  claim 32 , wherein when the inlet pressure is at a minimum the gas volume is at a maximum and wherein when the inlet pressure is at a maximum the gas volume is at a minimum. 
   
   
       34 . A method of compressing a gas, comprising the steps of:
 compressing the gas in a low pressure stage of a compressor;   providing a portion of the compressed gas from the low pressure stage to a cylinder; and   providing a remaining portion of the compressed gas from the low pressure stage and the portion of the compressed gas from the cylinder to the high pressure stage.   
   
   
       35 . The method according to  claim 34 , further comprising the step of adjusting a gas volume of the cylinder by an inlet pressure to the low pressure stage.