Hydraulic compressor system and method

Abstract

A compressor system comprises a gas source configured to supply a gas, at least one tube comprising at least one inlet and at least one outlet, at least one piston slidably disposed within the at least one tube and dividing the at least one tube into a first chamber and a second chamber, a tank configured to store a hydraulic fluid, a pump configured to pressurize the hydraulic fluid received from the tank and discharge the pressurized hydraulic fluid, a valve configured to control a flow of the pressurized hydraulic fluid from the pump to the second chamber and a flow of the hydraulic fluid from the second chamber to the tank, and a fluid source configured to provide a gaseous fluid different from the hydraulic fluid to the tank, such that the gaseous fluid pressurizes the hydraulic fluid stored within the tank.

Description

HYDRAULIC COMPRESSOR SYSTEM AND METHODTechnical Field

[0001] The present application relates to a hydraulic compressor system and a method of operating the hydraulic compressor system.Background

[0002] Reciprocating piston gas compressors have a cylinder and a piston slidably disposed within the cylinder. The cylinder and the piston define a compression chamber and a driving chamber opposite to the compression chamber. A gas is received and compressed in the compression chamber. In floating-piston-type reciprocating-piston gas compressors, a hydraulic drive mechanism may use a hydraulic fluid in the driving chamber for applying a hydraulic pressure to the driving chamber (i.e., a hydraulic side of the piston) to generate a forward stroke or a compression stroke. The hydraulic pressure is used to compress the gas received in the compression chamber (i.e., at a gas side of the piston). The incoming gas in the compression chamber or at the gas side is used to generate a return stroke or a retract stroke.

[0003] During the retract stroke, a flow of the hydraulic fluid from the pump as well as a flow of the hydraulic fluid from the hydraulic side of the piston, may pass through a restriction which may build back pressure in the compressor system. The energy required by the pump to pressurize the hydraulic fluid up to the back pressure may be wasted and may not produce any useful work. Further, the hydraulic fluid at a pressure equal to a gas pressure is discharged from the hydraulic side of the cylinder to an atmospheric pressure in each cycle and repressurized from the atmospheric pressure by the pump in a subsequent cycle. This may cause significantenergy losses in the compressor system (due to parasitic energy cost of compression) and may therefore reduce an efficiency of the compressor system.

[0004] In some cases, two pistons are used in compressor systems in tandem. Depending upon a cycle rate at which the compressor system is driven, there may be durations when one or both of the pistons are stationary. This may also cause significant energy losses in the compressor systems and may further reduce the efficiency of the compressor system.

[0005] The state of the art is therefore lacking in techniques for achieving a high efficiency in a compressor system (e.g., in the floating-piston-type reciprocatingpiston gas compressor). The present disclosure provides a hydraulic compressor system and a method of operating a hydraulic compressor system which provides an improved efficiency.Summary

[0006] An improved compressor system is provided. The compressor system comprises a gas source, at least one tube, at least one piston, a tank, a pump, a valve, and a fluid source. The gas source is configured to supply a gas. The at least one tube comprises at least one inlet and at least one outlet. The at least one inlet is disposed in fluid communication with the gas source and configured to receive the gas from the gas source. The at least one outlet is configured to discharge the gas after being pressurized by the compressor system. The at least one piston is slidably disposed within the at least one tube and divides the at least one tube into a first chamber and a second chamber. The first chamber is disposed in fluid communication with each of the at least one inlet and the at least one outlet. The second chamber is configured to receive a hydraulic fluid to drive the at least one piston in order to pressurize the gas. The tank is configured to store the hydraulic fluid. The pump comprises a pump inlet disposed in fluid communication with thetank and a pump outlet. The pump is configured to pressurize the hydraulic fluid received from the tank and discharge the pressurized hydraulic fluid via the pump outlet. The valve is disposed in fluid communication with the pump outlet of the pump, the tank, and the second chamber of the at least one tube. The valve is configured to control a flow of the pressurized hydraulic fluid from the pump to the second chamber and a flow of the hydraulic fluid from the second chamber to the tank. The fluid source is disposed in fluid communication with the tank and configured to provide a gaseous fluid different from the hydraulic fluid to the tank, such that the gaseous fluid pressurizes the hydraulic fluid stored within the tank.

[0007] An improved method of operating a compressor system is provided. The method comprises supplying, via at least one inlet, a first chamber of at least one tube with a gas from a gas source. The method further comprises pressurizing, via at least one piston slidably received within the at least one tube, the gas received within the first chamber. The at least one piston divides the at least one tube into the first chamber and a second chamber. The method further comprises discharging, via at least one outlet, the gas from the first chamber of the at least one tube after the gas is pressurized by the at least one piston. The method further comprises pressurizing, via a pump, a hydraulic fluid received from a tank. The method further comprises controlling, via a valve, a flow of the pressurized hydraulic fluid from a pump outlet to the second chamber of the at least one tube in order to drive the at least one piston. The method further comprises controlling, via the valve, a flow of the hydraulic fluid from the second chamber to the tank. The method further comprises supplying, via a fluid source, a gaseous fluid different from the hydraulic fluid to the tank, such that the gaseous fluid pressurizes the hydraulic fluid stored within the tank.Brief Description of the Drawings

[0008] FIG. 1 is schematic diagram illustrating a compressor system, according to an embodiment of the present disclosure;

[0009] FIG. 2 is schematic diagram illustrating a compressor system, according to another embodiment of the present disclosure;

[0010] FIG. 3 is schematic diagram illustrating a compressor system, according to yet another embodiment of the present disclosure;

[0011] FIG. 4 is schematic diagram illustrating a compressor system, according to yet another embodiment of the present disclosure;

[0012] FIG. 5 is schematic diagram illustrating a compressor system, according to yet another embodiment of the present disclosure;

[0013] FIG. 6 is schematic diagram illustrating a compressor system, according to yet another embodiment of the present disclosure; and

[0014] FIG. 7 is a flowchart illustrating a method of operating the compressor system, according to an embodiment of the present disclosure.Detailed Description

[0015] Referring to FIG. 1, there is shown a compressor system 100, according to an embodiment of the present disclosure. In some embodiments, the compressor system 100 can be for a vehicle, and can also be employed in marine, locomotive, mine haul, power generation, or stationary applications. In some embodiments, the compressor system 100 may be for an internal combustion engine.

[0016] The compressor system 100 comprises a gas source 110 configured to supply a gas 111. In some embodiments, the gas 111 is a gaseous fuel, which is asany fuel that is in the gas state at standard temperature and pressure defined herein to be zero degrees Celsius (0 °C) and one bar (1 bar). In some embodiments, the gas 111 may serve as a main fuel, for example, for the internal combustion engine. In some embodiments, the gas 111 is selected from the group consisting of ammonia, biogas, butane, ethane, hydrogen, natural gas, propane, and mixtures thereof.

[0017] The compressor system 100 further comprises at least one tube 120 comprising at least one inlet 130 and at least one outlet 135. The at least one inlet 130 is disposed in fluid communication with the gas source 110 and configured to receive the gas 111 from the gas source 110. Further, the at least one outlet 135 is configured to discharge the gas 111 after being pressurized by the compressor system 100.

[0018] The compressor system 100 further comprises at least one piston 150 slidably disposed within the at least one tube 120 and dividing the at least one tube 120 into a first chamber 122 and a second chamber 124. The at least one piston 150 is movable within the at least one tube 120. Particularly, the at least one piston 150 is reciprocable within the at least one tube 120.

[0019] The first chamber 122 is disposed in fluid communication with each of the at least one inlet 130 and the at least one outlet 135. In some embodiments, the at least one inlet 130 includes an inlet check valve that allows fluid flow into the first chamber 122 when a pressure upstream of the inlet check valve is greater than a pressure in the first chamber 122, for example by a cracking pressure of the inlet check valve. In some embodiments, the at least one outlet 135 includes an outlet check valve that allows fluid flow out of the first chamber 122 when a pressure downstream of the outlet check valve is less than the pressure in the first chamber 122, for example by a cracking pressure of the outlet check valve.

[0020] Further, the second chamber 124 is configured to receive a hydraulic fluid 161 to drive the at least one piston 150 in order to pressurize the gas 111. The at least one outlet 135 is configured to discharge the gas 111 after being pressurized by the at least one piston 150 of the compressor system 100. For example, when the pressure in the first chamber 122 rises above the pressure downstream from the outlet 135, the outlet 135 is configured to discharge the gas 111.

[0021] In some embodiments, the compressor system 100 may further comprise a piston seal (not shown) disposed between the at least one piston 150 and the at least one tube 120. The piston seal may substantially reduce a leakage of the gas 111 from the first chamber 122 to the second chamber 124 and / or a leakage of the hydraulic fluid 161 from the second chamber 124 to the first chamber 122.

[0022] The compressor system 100 further comprises a tank 160 configured to store the hydraulic fluid 161. In some embodiments, the tank 160 comprises a top end 162, a bottom end 164 opposite to the top end 162, and a pocket 165 disposed at the top end above a level 166 of the hydraulic fluid 161 stored within the tank 160. In some embodiments, the hydraulic fluid 161 may be a hydraulic oil.

[0023] The compressor system 100 further comprises a pump 170 comprising a pump inlet 172 and a pump outlet 174. The pump inlet 172 is disposed in fluid communication with the tank. The pump 170 is configured to pressurize the hydraulic fluid 161 received from the tank 160 and discharge the pressurized hydraulic fluid 161 via the pump outlet 174. In some embodiments, the pump 170 is a hydraulic pump. In some embodiments, the pump 170 is a fixed displacement hydraulic pump or a variable displacement hydraulic pump.

[0024] In some embodiments, the compressor system 100 may use a drive system 185 for driving or reciprocating the at least one piston 150. Specifically, the drivesystem 185 may drive the pump 170. In some embodiments, the drive system 185 may comprise a mechanical drive, an electrical drive, a pneumatic drive, or a hydraulic drive. In some embodiments, the drive system 185 may comprise a hydraulic motor, an electrical motor, a power-take-off from the internal combustion engine, mechanical levers, gears, etc.

[0025] The compressor system 100 further comprises a valve 180 disposed in fluid communication with the pump outlet 174 of the pump 170, the tank 160, and the second chamber 124 of the at least one tube 120. In some embodiments, the valve 180 is a hydraulic switch valve. In the illustrated embodiment of FIG. 1, the valve 180 is a 4 / 3 -way valve. However, in some other embodiments, the valve 180 may include any switch valve as per desired application attributes.

[0026] The valve 180 is configured to control a flow 182 of the pressurized hydraulic fluid 161 from the pump 170 to the second chamber 124 and a flow 184 of the hydraulic fluid 161 from the second chamber 124 to the tank 160.

[0027] The compressor system 100 further comprises a fluid source 190 disposed in fluid communication with the tank 160 and configured to provide a gaseous fluid 192 different from the hydraulic fluid 161 to the tank 160, such that the gaseous fluid 192 pressurizes the hydraulic fluid 161 stored within the tank 160. In some embodiments, the compressor system 100 further comprises a fluid line 194 fluidly communicating the fluid source 190 with the pocket 165 of the tank 160.

[0028] Referring to the illustrated embodiment of FIG. 1, in some embodiments, the at least one tube 120 comprises a first tube 126 and a second tube 128 separate from the first tube 126. In some embodiments, a partition (not shown) separates the first tube 126 from the second tube 128, whereby the first tube 126 is connected with or integrated with the second tube 128.

[0029] Further, in the illustrated embodiment of FIG. 1, the at least one piston 150 comprises a first piston 152 slidably disposed within the first tube 126 and a second piston 154 slidably disposed within the second tube 128. The first piston 152 is movable within the first tube 126 and second piston 154 is movable within the second tube 128. Particularly, the first piston 152 is reciprocable within the first tube 126 and the second piston 154 is reciprocable within the second tube 128.

[0030] Further, the compressor system 100 further comprises a rod 140 connecting the first piston 152 to the second piston 154. The rod 140 extends from the first piston 152 and extends through the partition (when present) to the second piston 154. Thus, the first piston 152 and the second piston 154 may be synchronized together. That is, the first piston 152 may be 180 degrees out of phase with the second piston 154, such that when the first piston 152 is in a compression stroke, the second piston 154 is in a suction stroke, and vice versa. Therefore, the compression stroke and the suction stroke of the compressor system 100 may be equal. In other words, there may be no dwell period in which the first piston 152 and / or the second piston 154 are stationary, while the other piston is not. This may significantly improve an efficiency of the compressor system 100.

[0031] In the illustrated embodiment of FIG. 1, the first piston 152 and the second piston 154 divide the first tube 126 and the second tube 128 into the respective first chambers 122-1, 122-2 and the respective second chambers 124-1, 124-2. Specifically, the first piston 152 divides the first tube 126 into the first chamber 122-1 and the second chamber 124-1 and the second piston 154 divides the second tube 128 into the first chamber 122-2 and the second chamber 124-2.

[0032] Further, in the illustrated embodiment of FIG. 1, the at least one inlet 130 comprises a pair of respective inlets 130-1, 130-2 disposed in fluid communication with the respective first chambers 122-1, 122-2 of the first tube 126 and the secondtube 128. Specifically, the inlet 130-1 is disposed in fluid communication with the first chamber 122-1 of the first tube 126 and the inlet 130-2 is disposed in fluid communication with the first chamber 122-2 of the second tube 128.

[0033] Similarly, in the illustrated embodiment of FIG. 1, the at least one outlet 135 comprises a pair of respective outlets 135-1, 135-2 disposed in fluid communication with the respective first chambers 122-1, 122-2 of the first tube 126 and the second tube 128. Specifically, the outlet 135-1 is disposed in fluid communication with the first chamber 122-1 of the first tube 126 and the outlet 135-2 is disposed in fluid communication with the first chamber 122-2 of the second tube 128. In some embodiments, a downstream side of the outlet 135-1 is fluidly connected with a downstream side of the outlet 135-2.

[0034] Further, in the illustrated embodiment of FIG. 1, the gas source 110 is in fluid communication with the respective inlets 130-1, 130-2 of the first tube 126 and the second tube 128. Specifically, the gas source 110 is in fluid communication with the inlet 130-1 of the first tube 126 and the inlet 130-2 of the second tube 128.

[0035] Furthermore, in the illustrated embodiment of FIG. 1, the valve 180 is disposed in fluid communication with the second chamber 124-1, 124-2 of each of the first tube 126 and the second tube 128, such that the pressurized hydraulic fluid 161 drives each of the first piston 152 and the second piston 154. Specifically, the valve 180 is disposed in fluid communication with the second chamber 124-1 of the first tube 126 and the second chamber 124-2 of the second tube 128, such that the pressurized hydraulic fluid 161 drives each of the first piston 152 slidably disposed within the first tube 126 and the second piston 154 slidably disposed within the second tube 128.

[0036] The valve 180 is configured to control the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 to the second chamber 124-1, 124-2 of each of the first tube 126 and the second tube 128. In other words, the valve 180 is configured to control the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 to the second chamber 124-1 of the first tube 126 and the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 to the second chamber 124-2 of the second tube 128. The valve 180 is further configured to control the flow 184 of the hydraulic fluid 161 from the second chamber 124-1, 124-2 of each of the first tube 126 and the second tube 128 to the tank 160. In other words, the valve 180 is configured to control the flow 184 of the hydraulic fluid 161 from the second chamber 124-1 of the first tube 126 to the tank 160 and the flow 184 of the hydraulic fluid 161 from the second chamber 124-2 of the second tube 128 to the tank 160.

[0037] In the illustrated embodiment of FIG. 1, the fluid source 190 is the gas source 110, such that the gaseous fluid 192 is the gas 111. Therefore, in such embodiments, the fluid line 194 fluidly communicates the gas source 110 with the pocket 165 of the tank 160 and the gas 111 pressurizes the hydraulic fluid 161 stored within the tank 160.

[0038] Thus, the hydraulic fluid 161 stored within the tank 160 is pressurized at a pressure exerted by the gas 111 from gas source 110. This may eliminate the discharge of the hydraulic fluid 161 to an atmospheric pressure in each cycle. Instead of the pressurized hydraulic fluid 161 discharging to the atmospheric pressure, the pressurized hydraulic fluid 161 may be discharged substantially to the pressure of gas 111 from gas source 110. Therefore, the pump 170 may not have to repressurize the hydraulic fluid 161 from the atmospheric pressure in a subsequent cycle. This may significantly reduce energy losses in the compressor system 100 that is otherwisecaused due to repressurizing the hydraulic fluid 161 from the atmospheric pressure in the subsequent cycle via the pump 170. This may therefore further improve the efficiency of the compressor system 100.

[0039] FIG. 2 shows a compressor system 200, according to another embodiment of the present disclosure wherein like parts in this and all other embodiments have like reference numerals and differences between embodiments are discussed.

[0040] The compressor system 200 is substantially similar and functionally equivalent to the compressor system 100 shown in FIG. 1. However, the compressor system 200 further comprises a diaphragm 210 disposed within the tank 160 and fluidly separating the hydraulic fluid 161 from the gaseous fluid 192.

[0041] In some embodiments, the compressor system 200 comprises a tank piston (not shown) disposed within the tank 160 and fluidly separating the hydraulic fluid 161 from the gaseous fluid 192. In some embodiments, the compressor system 200 further comprises a seal (not shown) between the tank piston and the tank 160 for fluidly sealing the hydraulic fluid 161 from the gaseous fluid 192. In some embodiments, the compressor system 200 comprises a gas charged pulsation damper (not shown) for fluidly separating the hydraulic fluid 161 from the gaseous fluid 192.

[0042] Therefore, the hydraulic fluid 161 and the gaseous fluid 192 may be kept physically separated. This may prevent any potential chemical reaction between the hydraulic fluid 161 and the gaseous fluid 192.

[0043] FIG. 3 shows a compressor system 300, according to yet another embodiment of the present disclosure wherein like parts in this and all other embodiments have like reference numerals and differences between embodiments are discussed.

[0044] The compressor system 300 is substantially similar and functionally equivalent to the compressor system 100 shown in FIG. 1. However, in the compressor system 300, the fluid source 190 comprises an additional compressor 310 configured to supply the gaseous fluid 192 to the tank 160. Further, in some embodiments, the gaseous fluid is air 340. Therefore, in such embodiments, the fluid line 194 allows fluid communication between the additional compressor 310 and the pocket 165 of the tank 160 and the air 340 pressurizes the hydraulic fluid 161 stored within the tank 160. In some embodiments, the additional compressor 310 may be an on-board air compressor. In some embodiments, the diaphragm 210 (or alternatively, the tank piston or the gas charge pulsation damper) may separate the air 340 from the hydraulic fluid 161.

[0045] Thus, the hydraulic fluid 161 stored within the tank 160 is pressurized at a pressure exerted by the air 340. This may eliminate the discharge of the hydraulic fluid 161 to the atmospheric pressure in each cycle. Therefore, the pump 170 may not have to repressurize the hydraulic fluid 161 from the atmospheric pressure in the subsequent cycle. This may significantly reduce energy losses in the compressor system 300 caused due to repressurizing the hydraulic fluid 161 from the atmospheric pressure in the subsequent cycle via the pump 170. This may therefore further improve the efficiency of the compressor system 300.

[0046] In some embodiments, the compressor system 300 further comprises a controller 330 communicably coupled to the additional compressor 310 and configured to control the additional compressor 310 in order to adjust a pressure of the gaseous fluid 192 supplied by the additional compressor 310. In other words, the controller 330 is configured to control the additional compressor 310 in order to adjust the pressure of the air 340 supplied by the additional compressor 310. In some embodiments, the controller 330 may be integrated with the additional compressor310. In some embodiments, the pressure of the gaseous fluid 192 (i.e., the air 340) supplied by the additional compressor 310 is substantially equal to the pressure exerted by the gas 111.

[0047] In some embodiments, the controller 330 is an electronic controller, such as a computer comprising one or more processors and one or more memories, including a permanent memory, such as FLASH or EEPROM, and a temporary memory, such as SRAM or DRAM, for storing and executing a program. In some embodiments, the controller 330 may be an engine control unit (ECU) of, for example, the internal combustion engine.

[0048] In some embodiments, the additional compressor 310 may be a high- pressure compressor. In some embodiments, the additional compressor 310 may be a low-pressure compressor. In some embodiments, the compressor system 300 further comprises a pressure multiplier 320 fluidly disposed between the additional compressor 310 and the tank 160. In some embodiments, the pressure multiplier 320 may be used when the additional compressor 310 is the low-pressure compressor. In some embodiments, the controller 330 may further be communicably coupled to the pressure multiplier 320.

[0049] FIG. 4 shows a compressor system 400, according to yet another embodiment of the present disclosure wherein like parts in this and all other embodiments have like reference numerals and differences between embodiments are discussed.

[0050] The compressor system 400 is substantially similar and functionally equivalent to the compressor system 100 shown in FIG. 1. However, in the compressor system 400, the at least one tube 120 comprises a single tube 420 comprising a first end 402 and a second end 404 opposite to the first end 402.Further, the at least one inlet 130 comprises a single inlet 430 and the at least one outlet 135 comprises a single outlet 435.

[0051] In the illustrated embodiment of FIG. 4, the compressor system 400 further comprises a partition 445 dividing the single tube 420 into a first tube portion 426 extending from the first end 402 to the partition 445 and a second tube portion 428 fluidly isolated from the first tube portion 426 and extending from the second end 404 to the partition 445.

[0052] Further, in the illustrated embodiment of FIG. 4, the at least one piston 150 comprises a first piston 452 slidably disposed within the first tube portion 426 and a second piston 454 slidably disposed within the second tube portion 428.

[0053] The first piston 452 and the second piston 454 divide the first tube portion 426 and the second tube portion 428 into the respective first chambers 422-1, 422-2 and the respective second chambers 424-1, 424-2. Specifically, the first piston 452 divides the first tube portion 426 into the first chamber 422- 1 and the second chamber 424-1 and the second piston 454 divides the second tube portion 428 into the first chamber 422-2 and the second chamber 424-2. As is shown in FIG. 4, the single inlet 430 and the single outlet 435 are disposed in fluid communication with the first chamber 422-1 of the first tube portion 426. Further, the second chamber 424-2 of the second tube portion 428 receives the hydraulic fluid 161 to drive the second piston 454 in order to pressurize the gas 111.

[0054] Furthermore, in the illustrated embodiment of FIG. 4, a rod 440 extends through the partition 445 and connects the first piston 452 to the second piston 454. Thus, the first piston 452 and the second piston 454 may be synchronized together. That is, the first piston 452 may be 180 degrees out of phase with the second piston 454, such that when the first piston 452 is moving towards the first end 402 thesecond piston 454 is moving away from the second end 404, and vice versa. Therefore, a compression stroke and a suction stroke of the compressor system 400 may be equal. In other words, there may be no dwell period in which the first piston 452 and / or the second piston 454 are stationary, while the other piston is not. This may significantly improve an efficiency of the compressor system 400.

[0055] As shown in FIG. 4, the valve 180 is disposed in fluid communication with the each of the first chamber 422-2 and the second chamber 424-2 of the second tube portion 428, such that the pressurized hydraulic fluid 161 drives the second piston 454 and the second piston 454 drives the first piston 452 via the rod 440.

[0056] The valve 180 is further configured to control the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 to each of the first chamber 422-2 and the second chamber 424-2 of the second tube portion 428. Further, the valve 180 is configured to control the flow 184 of the hydraulic fluid 161 from each of the first chamber 422-2 and the second chamber 424-2 of the second tube portion 428 to the tank 160.

[0057] In some embodiments, the pressure of the gas 111 from gas source 110 may drive the first piston 452 and the second piston away from the first end 402 and towards the second end 404 during a suction stroke. In some embodiments, a combined pressure of the pressure of the gas 111 from the gas source 110 acting on the first piston 452 and the pressure of the flow 182 of the pressurized hydraulic fluid entering the second chamber 424-2 and acting on the second piston 454 drives the first piston 452 and the second piston 454 away from the first end 402 and towards the second end 404 during the suction stroke.

[0058] FIG. 5 shows a compressor system 500, according to yet another embodiment of the present disclosure wherein like parts in this and all otherembodiments have like reference numerals and differences between embodiments are discussed.

[0059] The compressor system 500 is substantially similar and functionally equivalent to the compressor system 100 shown in FIG. 1. However, in the compressor system 500, the at least one tube 120 comprises a single tube 520 comprising a first end 502 and a second end 504 opposite to the first end 502. The compressor system 500 further comprises a first partition 545 disposed proximal to the first end 502 and a second partition 546 spaced apart from the first partition 545 and disposed proximal to the second end 504.

[0060] As shown in FIG. 5, the first partition 545 and the second partition 546 divide the single tube 520 into a first tube portion 526 extending from the first end 502 to the first partition 545, a second tube portion 528 fluidly isolated from the first tube portion 526 and extending from the second end 504 to the second partition 546, and a third tube portion 527 fluidly isolated from each of the first tube portion 526 and the second tube portion 528 and extending between the first partition 545 and the second partition 546.

[0061] In the illustrated embodiment of FIG. 5, the at least one piston 150 comprises a first piston 552 slidably disposed within the first tube portion 526, a second piston 554 slidably disposed within the second tube portion 528, and a third piston 556 slidably disposed within the third tube portion 527. The first piston 552, the second piston 554, and the third piston 556 divide the first tube portion 526, the second tube portion 528, and the third tube portion 527 into the respective first chambers 522-1, 522-2, 522-3 and the respective second chambers 524-1, 524-2, 524- 3. Specifically, the first piston 552 divides the first tube portion 526 into the first chamber 522-1 and the second chamber 524-1, the second piston 554 divides the second tube portion 528 into the first chamber 522-2 and the second chamber 524-2,and the third piston 556 divides the third tube portion 527 into the first chamber 522- 3 and the second chamber 524-3.

[0062] Further, in the illustrated embodiment of FIG. 5, the at least one inlet 130 comprises a pair of respective inlets 530-1, 530-2 disposed in fluid communication with the respective first chambers 522-1, 522-2 of the first tube portion 526 and the second tube portion 528. Specifically, the inlet 530-1 is disposed in fluid communication with the first chamber 522-1 of the first tube portion 526 and the inlet 530-2 is disposed in fluid communication with the first chamber 522-2 of the second tube portion 528.

[0063] Similarly, in the illustrated embodiment of FIG. 5, the at least one outlet 135 comprises a pair of respective outlets 535-1, 535-2 disposed in fluid communication with the respective first chambers 522-1, 522-2 of the first tube portion 526 and the second tube portion 528. Specifically, the outlet 535-1 is disposed in fluid communication with the first chamber 522- 1 of the first tube portion 526 and the outlet 535-2 is disposed in fluid communication with the first chamber 522-2 of the second tube portion 528. In some embodiments, a downstream side of outlet 535-1 is fluidly connected with a downstream side of outlet 535-2.

[0064] The gas source 110 is in fluid communication with at least the inlet 530-1 of the first tube portion 526. In the illustrated embodiment of FIG. 5, the gas source 110 is further in fluid communication with the inlet 530-2 of the second tube portion 528.

[0065] The compressor system 500 further comprises a first rod 542 extending through the first partition 545 and connecting the first piston 552 to the third piston 556. The compressor system 500 further comprises a second rod 544 extending through the second partition 546 and connecting the second piston 554 to the third piston 556. Thus, the first piston 552, the second piston 554, and the third piston 556may be synchronized together. That is, the first piston 552 may be 180 degrees out of phase with the second piston 554, such that when the first piston 552 is in a compression stroke the second piston 554 is in a suction stroke, and vice versa. Therefore, the compression stroke and the suction stroke of the compressor system 500 may be equal. In other words, there may be no dwell period in which the first piston 552, the second piston 554, and / or the third piston 556 are stationary. This may substantially improve the efficiency of the compressor system 500.

[0066] As shown in FIG. 5, the valve 180 is disposed in fluid communication with the each of the first chamber 522-3 and the second chamber 524-3 of the third tube portion 527, such that the pressurized hydraulic fluid 161 drives the third piston 556 and the third piston 556 drives the first and second pistons 552, 554 via the respective first and second rods 542, 544.

[0067] The valve 180 is further configured to control the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 to each of the first chamber 522-3 and the second chamber 524-3 of the third tube portion 527. Further, the valve 180 is further configured to control the flow 184 of the hydraulic fluid 161 from each of the first chamber 522-3 and the second chamber 524-3 of the third tube portion 527 to the tank 160.

[0068] FIG. 6 shows a compressor system 600, according to yet another embodiment of the present disclosure wherein like parts in this and all other embodiments have like reference numerals and differences between embodiments are discussed.

[0069] The compressor system 600 is substantially similar and functionally equivalent to the compressor system 500 shown in FIG. 5. However, in the compressor system 600, the outlet 535-1 of the first tube portion 526 is disposed influid communication with the inlet 530-2 of the second tube portion 528, such that the first chamber 522-2 of the second tube portion 528 receives a pressurized gas from the first chamber 522-1 of the first tube portion 526. Therefore, the compressor system 600 may be a two-stage compressor.

[0070] Referring to FIG. 7, there is shown a flowchart illustrating a method 700 of operating the compressor systems 100, 200, 300, 400, 500, 600 shown in FIGS. 1, 2, 3, 4, 5, and 6, respectively, according to an embodiment of the present disclosure.

[0071] The method 700 will be described with reference to FIGS. 1, 2, 3, 4, 5, and 6. The method 700 comprises the following steps:

[0072] At step 702, the method 700 comprises supplying, via the at least one inlet 130, the first chamber 122 of the at least one tube 120 with the gas 111 from the gas source 110.

[0073] At step 704, the method 700 comprises pressurizing, via the at least one piston 150 slidably received within the at least one tube 120, the gas 111 received within the first chamber 122. As discussed above, the at least one piston 150 divides the at least one tube 120 into the first chamber 122 and the second chamber 124.

[0074] At step 706, the method 700 comprises discharging, via the at least one outlet 135, the gas 111 from the first chamber 122 of the at least one tube 120 after the gas 111 is pressurized by the at least one piston 150.

[0075] At step 708, the method 700 comprises pressurizing, via the pump 170, the hydraulic fluid 161 received from the tank 160.

[0076] At step 710, the method 700 comprises controlling, via the valve 180, the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 to thesecond chamber 124 of the at least one tube 120 in order to drive the at least one piston 150.

[0077] At step 712, the method 700 comprises controlling, via the valve 180, the flow 184 of the hydraulic fluid 161 from the second chamber 124 to the tank 160.

[0078] At step 714, the method 700 comprises supplying, via the fluid source 190, the gaseous fluid 192 different from the hydraulic fluid 161 to the tank 160, such that the gaseous fluid 192 pressurizes the hydraulic fluid 161 stored within the tank 160.

[0079] In some embodiments, the method 700 further comprises fluidly communicating the fluid source 190 with the pocket 165 of the tank 160. As discussed above, the pocket 165 is disposed above the level 166 of the hydraulic fluid 161 stored within the tank 160.

[0080] In some embodiments, as shown in FIG. 2, the method 700 further comprises fluidly separating, via the diaphragm 210, the hydraulic fluid 161 from the gaseous fluid 192. In some embodiments, the method 700 further comprises fluidly separating, via the tank piston, the hydraulic fluid 161 from the gaseous fluid 192. In some embodiments, the method 700 further comprises fluidly sealing, via the seal between the tank piston and the tank 160, the hydraulic fluid 161 from the gaseous fluid 192.

[0081] As shown in FIGS. 1, 2, 4, 5, and 6, in some embodiments, the fluid source 190 is the gas source 110, such that the gaseous fluid 192 is the gas 111.

[0082] As shown in FIG. 3, in some embodiments, the fluid source 190 comprises the additional compressor 310. In such embodiments, the method 700 further comprises pressurizing, via the additional compressor 310, the gaseous fluid 192 that is supplied to the tank 160. In some embodiments, the gaseous fluid 192 is the air340. In some embodiments, the method 700 further comprises controlling the additional compressor 310 in order to adjust the pressure of the gaseous fluid 192 supplied by the additional compressor 310.

[0083] In some embodiments, the method 700 further comprises fluidly disposing the pressure multiplier 320 fluidly between the additional compressor 310 and the tank 160.

[0084] Referring to FIGS. 1, 2, and 3, in some embodiments, supplying the first chamber 122-1, 122-2 further comprises supplying, via the respective inlets 130-1, 130-2, the gas 111 to the first chamber 122-1, 122-2 of each of the first tube 126 and the second tube 128.

[0085] Further, in some embodiments, pressurizing the gas 111 further comprises pressurizing, via the first and second pistons 152, 154, the gas 111 received within the respective first chambers 122-1, 122-2 of the first and second tubes 126, 128.

[0086] Furthermore, in some embodiments, discharging the gas 111 further comprises discharging, via the respective outlets 135-1, 135-2, the gas 111 from the respective first chambers 122-1, 122-2 of the first and second tubes 126, 128 after the gas 111 is pressurized by the respective first and second pistons 152, 154. In other words, in some embodiments, discharging the gas 111 further comprises discharging, via the outlet 135-1, the gas 111 from the first chamber 122-1 of the first tube 126 after the gas 111 is pressurized by the first piston 152 and discharging, via the outlet 135-2, the gas 111 from the first chamber 122-2 of the second tube 128 after the gas 111 is pressurized by the second piston 154.

[0087] In some embodiments, controlling the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 further comprises alternatively fluidlycommunicating, via the valve 180, the pump outlet 174 with the respective second chambers 124-1, 124-2 of the first tube 126 and the second tube 128. Further, controlling the flow 184 of the hydraulic fluid 161 to the tank 160 further comprises alternatively fluidly communicating, via the valve 180, the tank 160 with the respective second chambers 124-1, 124-2 of the first tube 126 and the second tube 128.

[0088] In some embodiments, the method 700 further comprises connecting, via the rod 140, the first piston 152 to the second piston 154.

[0089] Referring to FIG. 4, in some embodiments, the method 700 further comprises dividing, via the partition 445, the single tube 420 into the first tube portion 426 extending from the first end 402 to the partition 445 and the second tube portion 428 fluidly isolated from the first tube portion 426 and extending from the second end 404 to the partition 445. In some embodiments, the method 700 further comprises connecting, via the rod 440, the first piston 452 to the second piston 454.

[0090] In some embodiments, supplying the first chamber 422-1 further comprises supplying, via the respective single inlet 430, the gas 111 to the first chamber 422-1 of the first tube portion 426.

[0091] Further, in some embodiments, pressurizing the gas 111 further comprises pressurizing, via the first piston 452, the gas 111 received within the first chamber 422-1 of the first tube portion 426.

[0092] Furthermore, in some embodiments, discharging the gas 111 further comprises discharging, via the single outlet 435, the gas 111 from the first chamber 422-1 of the first tube portion 426 after the gas 111 is pressurized by the first piston 452.

[0093] In some embodiments, controlling the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 further comprises alternatively fluidly communicating, via the valve 180, the pump outlet 174 with the first chamber 422-2 and the second chamber 424-2 of the second tube portion 428.

[0094] Further, controlling the flow 184 of the hydraulic fluid 161 to the tank 160 further comprises alternatively fluidly communicating, via the valve 180, the tank 160 with the first chamber 422-2 and the second chamber 424-2 of the second tube portion 428.

[0095] Referring to FIGS. 5 and 6, in some embodiments, the method 700 further comprises dividing, via the first partition 545 and the second partition 546, the single tube 520 into the first tube portion 526 extending from the first end 502 to the first partition 545, the second tube portion 528 fluidly isolated from the first tube portion 526 and extending from the second end 504 to the second partition 546, and the third tube portion 527 fluidly isolated from each of the first tube portion 526 and the second tube portion 528 and extending between the first partition 545 and the second partition 546.

[0096] In some embodiments, the method 700 further comprises connecting, via the first rod 542, the first piston 552 to the third piston 556 and connecting, via the second rod 544, the second piston 554 to the third piston 556.

[0097] In some embodiments, the method 700 further comprises fluidly communicating the gas source 110 with at least the inlet 530-1 of the first tube portion 526.

[0098] In some embodiments, supplying the first chamber 522-1 further comprises supplying, via the respective inlet 530-1, the gas 111 to the first chamber 522-1 of the first tube portion 526.

[0099] Further, in some embodiments, pressurizing the gas 111 further comprises pressurizing, via the first and second pistons 552, 524, the gas 111 received within the respective first chambers 522-1, 522-2 of the first and second tube portions 526, 528.

[0100] Furthermore, in some embodiments, discharging the gas 111 further comprises discharging, via the respective outlets 535-1, 535-2, the gas 111 from the respective first chambers 522-1, 522-2 of the first and second tube portions 526, 528 after the gas 111 is pressurized by the respective first and second pistons 552, 524.

[0101] In some embodiments, controlling the flow 182 of the pressurized hydraulic fluid 161 from the pump outlet 174 further comprises alternatively fluidly communicating, via the valve 180, the pump outlet 174 with the first chamber 522-3 and the second chamber 524-3 of the third tube portion 527.

[0102] Further, controlling the flow 184 of the hydraulic fluid 161 to the tank 160 further comprises alternatively fluidly communicating, via the valve 180, the tank 160 with the first chamber 522-3 and the second chamber 524-3 of the third tube portion 527.

[0103] Referring to FIG. 5, in some embodiments, supplying the first chamber 522- 2 further comprises supplying, via the respective inlet 530-2, the gas 111 to the first chamber 522-2 of the second tube portion 528.

[0104] Referring to FIG. 6, in some embodiments, the method 700 further comprises fluidly communicating the outlet 535-1 of the first tube portion 526 withthe inlet 530-2 of the second tube portion 528, such that the first chamber 522-2 of the second tube portion 528 receives a pressurized gas from the first chamber 522-1 of the first tube portion 526.

[0105] Referring to FIGS. 1, 2, 3, 4, 5, 6, and 7, the compressor systems 100, 200, 300, 400, 500, 600 and the method 700 may substantially reduce the energy losses that may be caused by the discharge of the hydraulic fluid 161 to the atmospheric pressure in each cycle. The compressor systems 100, 200, 300, 400, 500, 600 and the method 700 may further reduce the energy losses caused due to the dwell period of the at least one piston 150. The compressor systems 100, 200, 300, 400, 500, 600 shown in FIGS. 1, 2, 3, 4, 5, 6 and the method 700 shown in FIG. 7 may therefore provide an improved efficiency by substantially reducing the energy losses.

[0106] While particular elements, embodiments, and applications of the present invention have been shown and described, it will be understood, that the invention is not limited thereto since modifications can be made by those skilled in the art without departing from the scope of the present disclosure, particularly in light of the foregoing teachings.

Claims

What is claimed is:

1. A compressor system comprising: a gas source configured to supply a gas; at least one tube comprising at least one inlet and at least one outlet, wherein the at least one inlet is disposed in fluid communication with the gas source and configured to receive the gas from the gas source, and wherein the at least one outlet is configured to discharge the gas after being pressurized by the compressor system; at least one piston slidably disposed within the at least one tube and dividing the at least one tube into a first chamber and a second chamber, wherein the first chamber is disposed in fluid communication with each of the at least one inlet and the at least one outlet, and wherein the second chamber is configured to receive a hydraulic fluid to drive the at least one piston in order to pressurize the gas; a tank configured to store the hydraulic fluid; a pump comprising a pump inlet disposed in fluid communication with the tank and a pump outlet, wherein the pump is configured to pressurize the hydraulic fluid received from the tank and discharge the pressurized hydraulic fluid via the pump outlet; a valve disposed in fluid communication with the pump outlet of the pump, the tank, and the second chamber of the at least one tube, wherein the valve is configured to control a flow of the pressurized hydraulic fluid from the pump to the second chamber and a flow of the hydraulic fluid from the second chamber to the tank; and a fluid source disposed in fluid communication with the tank and configured to provide a gaseous fluid different from the hydraulic fluid to thetank, such that the gaseous fluid pressurizes the hydraulic fluid stored within the tank.

2. The compressor system of claim 1, wherein the at least one tube comprises a first tube and a second tube separate from the first tube, wherein the at least one piston comprises a first piston slidably disposed within the first tube and a second piston slidably disposed within the second tube, the first piston and the second piston dividing the first tube and the second tube into the respective first chambers and the respective second chambers, the at least one inlet comprising a pair of respective inlets disposed in fluid communication with the respective first chambers of the first tube and the second tube, the at least one outlet comprising a pair of respective outlets disposed in fluid communication with the respective first chambers of the first tube and the second tube, wherein the gas source is in fluid communication with the respective inlets of the first tube and the second tube, wherein the valve is disposed in fluid communication with the second chamber of each of the first tube and the second tube, such that the pressurized hydraulic fluid drives each of the first piston and the second piston, and wherein the valve is further configured to: control the flow of the pressurized hydraulic fluid from the pump outlet to the second chamber of each of the first tube and the second tube; and control the flow of the hydraulic fluid from the second chamber of each of the first tube and the second tube to the tank.

3. The compressor system of claim 2, further comprising a rod connecting the first piston to the second piston.

4. The compressor system of claim 3, wherein a partition separates the first tube from the second tube, and wherein the rod extending from the first piston extends through the partition to the second piston.

5. The compressor system of claim 1, wherein the at least one tube comprises a single tube comprising a first end and a second end opposite to the first end, the at least one inlet comprising a single inlet, the at least one outlet comprising a single outlet, the compressor system further comprising: a partition dividing the single tube into a first tube portion extending from the first end to the partition and a second tube portion fluidly isolated from the first tube portion and extending from the second end to the partition, the at least one piston comprising a first piston slidably disposed within the first tube portion and a second piston slidably disposed within the second tube portion, the first piston and the second piston dividing the first tube portion and the second tube portion into the respective first chambers and the respective second chambers, wherein the single inlet and the single outlet are disposed in fluid communication with the first chamber of the first tube portion; and a rod extending through the partition and connecting the first piston to the second piston; wherein the valve is disposed in fluid communication with the each of the first chamber and the second chamber of the second tube portion, such that the pressurized hydraulic fluid drives the second piston and the second piston drives the first piston via the rod, and wherein the valve is further configured to: control the flow of the pressurized hydraulic fluid from the pump outlet to each of the first chamber and the second chamber of the second tube portion; andcontrol the flow of the hydraulic fluid from each of the first chamber and the second chamber of the second tube portion to the tank.

6. The compressor system of claim 1, wherein the at least one tube comprises a single tube comprising a first end and a second end opposite to the first end, the compressor system further comprising: a first partition disposed proximal to the first end and a second partition spaced apart from the first partition and disposed proximal to the second end, the first partition and the second partition dividing the single tube into a first tube portion extending from the first end to the first partition, a second tube portion fluidly isolated from the first tube portion and extending from the second end to the second partition, and a third tube portion fluidly isolated from each of the first tube portion and the second tube portion and extending between the first partition and the second partition, the at least one piston comprising a first piston slidably disposed within the first tube portion, a second piston slidably disposed within the second tube portion, and a third piston slidably disposed within the third tube portion, the first piston, the second piston, and the third piston dividing the first tube portion, the second tube portion, and the third tube portion into the respective first chambers and the respective second chambers, the at least one inlet comprising a pair of respective inlets disposed in fluid communication with the respective first chambers of the first tube portion and the second tube portion, the at least one outlet comprising a pair of respective outlets disposed in fluid communication with the respective first chambers of the first tube portion and the second tube portion, wherein the gas source is in fluid communication with at least the inlet of the first tube portion;a first rod extending through the first partition and connecting the first piston to the third piston; and a second rod extending through the second partition and connecting the second piston to the third piston; wherein the valve is disposed in fluid communication with the each of the first chamber and the second chamber of the third tube portion, such that the pressurized hydraulic fluid drives the third piston and the third piston drives the first and second pistons via the respective first and second rods, and wherein the valve is further configured to: control the flow of the pressurized hydraulic fluid from the pump outlet to each of the first chamber and the second chamber of the third tube portion; and control the flow of the hydraulic fluid from each of the first chamber and the second chamber of the third tube portion to the tank.

7. The compressor system of claim 6, wherein the gas source is further in fluid communication with the inlet of the second tube portion.

8. The compressor system of claim 6, wherein the outlet of the first tube portion is disposed in fluid communication with the inlet of the second tube portion, such that the first chamber of the second tube portion receives a pressurized gas from the first chamber of the first tube portion.

9. The compressor system of claim 1, wherein the tank comprises a top end, a bottom end opposite to the top end, and a pocket disposed at the top end above a level of the hydraulic fluid stored within the tank, the compressor systemfurther comprising a fluid line fluidly communicating the fluid source with the pocket of the tank.

10. The compressor system of claim 1, further comprising a diaphragm disposed within the tank and fluidly separating the hydraulic fluid from the gaseous fluid.

11. The compressor system of claim 1, further comprising a tank piston disposed within the tank and fluidly separating the hydraulic fluid from the gaseous fluid.

12. The compressor system of claim 11, further comprising a seal between the tank piston and the tank fluidly sealing the hydraulic fluid from the gaseous fluid.

13. The compressor system of claim 1, wherein the fluid source is the gas source, such that the gaseous fluid is the gas.

14. The compressor system of claim 1, wherein the fluid source comprises an additional compressor configured to supply the gaseous fluid to the tank.

15. The compressor system of claim 14, further comprising a pressure multiplier fluidly disposed between the additional compressor and the tank.

16. The compressor system of claim 14, further comprising a controller communicably coupled to the additional compressor and configured to control the additional compressor in order to adjust a pressure of the gaseous fluid supplied by the additional compressor.

17. The compressor system of claim 14, wherein the gaseous fluid is air.

18. A method of operating a compressor system, the method comprising: supplying, via at least one inlet, a first chamber of at least one tube with a gas from a gas source; pressurizing, via at least one piston slidably received within the at least one tube, the gas received within the first chamber, the at least one piston dividing the at least one tube into the first chamber and a second chamber; discharging, via at least one outlet, the gas from the first chamber of the at least one tube after the gas is pressurized by the at least one piston; pressurizing, via a pump, a hydraulic fluid received from a tank; controlling, via a valve, a flow of the pressurized hydraulic fluid from a pump outlet to the second chamber of the at least one tube in order to drive the at least one piston; controlling, via the valve, a flow of the hydraulic fluid from the second chamber to the tank; and supplying, via a fluid source, a gaseous fluid different from the hydraulic fluid to the tank, such that the gaseous fluid pressurizes the hydraulic fluid stored within the tank.

19. The method of claim 18, wherein the at least one tube comprises a first tube and a second tube separate from the first tube, wherein the at least one piston comprises a first piston slidably disposed within the first tube and a second piston slidably disposed within the second tube, the first piston and the second piston dividing the first tube and the second tube into the respective first chambers and the respective second chambers, the at least one inlet comprising a pair of respective inlets disposed in fluid communication with the respective first chambers of the first tube and the second tube, the at least one outletcomprising a pair of respective outlets disposed in fluid communication with the respective first chambers of the first tube and the second tube, wherein: supplying the first chamber further comprises supplying, via the respective inlets, the gas to the first chamber of each of the first tube and the second tube; pressurizing the gas further comprises pressurizing, via the first and second pistons, the gas received within the respective first chambers of the first and second tubes; discharging the gas further comprises discharging, via the respective outlets, the gas from the respective first chambers of the first and second tubes after the gas is pressurized by the respective first and second pistons; controlling the flow of the pressurized hydraulic fluid from the pump outlet further comprises alternatively fluidly communicating, via the valve, the pump outlet with the respective second chambers of the first tube and the second tube; and controlling the flow of the hydraulic fluid to the tank further comprises alternatively fluidly communicating, via the valve, the tank with the respective second chambers of the first tube and the second tube.

20. The method of claim 19, further comprising, connecting, via a rod, the first piston to the second piston.

21. The method of claim 20, wherein a partition separates the first tube from the second tube, and wherein the rod extending from the first piston extends through the partition to the second piston.

22. The method of claim 18, wherein the at least one tube comprises a single tube comprising a first end and a second end opposite to the first end, the at least one inlet comprising a single inlet, the at least one outlet comprising a single outlet, the method further comprising: dividing, via a partition, the single tube into a first tube portion extending from the first end to the partition and a second tube portion fluidly isolated from the first tube portion and extending from the second end to the partition, the at least one piston comprising a first piston slidably disposed within the first tube portion and a second piston slidably disposed within the second tube portion, the first piston and the second piston dividing the first tube portion and the second tube portion into the respective first chambers and the respective second chambers, wherein the single inlet and the single outlet are disposed in fluid communication with the first chamber of the first tube portion; and connecting, via a rod, the first piston to the second piston.

23. The method of claim 22, wherein: supplying the first chamber further comprises supplying, via the respective single inlet, the gas to the first chamber of the first tube portion; pressurizing the gas further comprises pressurizing, via the first piston, the gas received within the first chambers of the first tube portion; discharging the gas further comprises discharging, via the single outlet, the gas from the first chamber of the first tube portion after the gas is pressurized by the first piston; controlling the flow of the pressurized hydraulic fluid from the pump outlet further comprises alternatively fluidly communicating, via the valve, thepump outlet with the first chamber and the second chamber of the second tube portion; and controlling the flow of the hydraulic fluid to the tank further comprises alternatively fluidly communicating, via the valve, the tank with the first chamber and the second chamber of the second tube portion.

24. The method of claim 18, wherein the at least one tube comprises a single tube comprising a first end and a second end opposite to the first end, the method further comprising: dividing, via a first partition and a second partition, the single tube into a first tube portion extending from the first end to the first partition, a second tube portion fluidly isolated from the first tube portion and extending from the second end to the second partition, and a third tube portion fluidly isolated from each of the first tube portion and the second tube portion and extending between the first partition and the second partition, the at least one piston comprising a first piston slidably disposed within the first tube portion, a second piston slidably disposed within the second tube portion, and a third piston slidably disposed within the third tube portion, the first piston, the second piston, and the third piston dividing the first tube portion, the second tube portion, and the third tube portion into the respective first chambers and the respective second chambers, the at least one inlet comprising a pair of respective inlets disposed in fluid communication with the respective first chambers of the first tube portion and the second tube portion, the at least one outlet comprising a pair of respective outlets disposed in fluid communication with the respective first chambers of the first tube portion and the second tube portion;fluidly communicating the gas source with at least the inlet of the first tube portion; connecting, via a first rod, the first piston to the third piston; and connecting, via a second rod, the second piston to the third piston.

25. The method of claim 24, wherein: supplying the first chamber further comprises supplying, via the respective inlet, the gas to the first chamber of the first tube portion; pressurizing the gas further comprises pressurizing, via the first and second pistons, the gas received within the respective first chambers of the first and second tube portions; discharging the gas further comprises discharging, via the respective outlets, the gas from the respective first chambers of the first and second tube portions after the gas is pressurized by the respective first and second pistons; controlling the flow of the pressurized hydraulic fluid from the pump outlet further comprises alternatively fluidly communicating, via the valve, the pump outlet with the first chamber and the second chamber of the third tube portion; and controlling the flow of the hydraulic fluid to the tank further comprises alternatively fluidly communicating, via the valve, the tank with the first chamber and the second chamber of the third tube portion.

26. The method of claim 25, supplying the first chamber further comprises supplying, via the respective inlet, the gas to the first chamber of the second tube portion.

27. The method of claim 25, further comprising fluidly communicating the outlet of the first tube portion with the inlet of the second tube portion, such that thefirst chamber of the second tube portion receives a pressurized gas from the first chamber of the first tube portion.

28. The method of claim 18, further comprising fluidly communicating the fluid source with a pocket of the tank, wherein the pocket is disposed above a level of the hydraulic fluid stored within the tank.

29. The method of claim 18, further comprising fluidly separating, via a diaphragm, the hydraulic fluid from the gaseous fluid.

30. The method of claim 18, further comprising fluidly separating, via a tank piston, the hydraulic fluid from the gaseous fluid.

31. The method of claim 30, further comprising fluidly sealing, via a seal between the tank piston and the tank, the hydraulic fluid from the gaseous fluid.

32. The method of claim 18, wherein the fluid source is the gas source, such that the gaseous fluid is the gas.

33. The method of claim 18, wherein the fluid source comprises an additional compressor, the method further comprising pressurizing, via the additional compressor, the gaseous fluid that is supplied to the tank.

34. The method of claim 33, further comprising fluidly disposing a pressure multiplier fluidly between the additional compressor and the tank.

35. The method of claim 33, further comprising controlling the additional compressor in order to adjust a pressure of the gaseous fluid supplied by the additional compressor.

36. The method of claim 33, wherein the gaseous fluid is air.

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