Compressor system and method

Abstract

A compressor system includes a compressor, a storage vessel, and a control valve. The compressor includes a cylinder having a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a compression chamber defined between the first end and the piston, and a driving chamber defined between the piston and the second end. The compression chamber receives a gas therein. The storage vessel is in fluid communication with the driving chamber and is configured to store the gas which leaks from the compression chamber to the driving chamber. The control valve is disposed in fluid communication with the storage vessel and the compression chamber and is configured to control a flow of the gas from the storage vessel to the compression chamber.

Description

COMPRESSOR SYSTEM AND METHODTechnical Field

[0001] The present application relates to a compressor system comprising a compressor and a method for managing an internal gas leakage in the compressor.Background

[0002] Because of its ready availability, low cost, and potential for reducing particulate emissions, gaseous fuels are gaining acceptance as a fuel for internal combustion engines. Gaseous fuels may have a potential to replace liquid fuels, such as diesel, in internal combustion engines while achieving similar performance to liquid-fueled engines, but with lower particulate matter and / or nitrogen oxide (NOx) emissions.

[0003] The internal combustion engines using the gaseous fuels as a main fuel typically comprise an on-board reciprocating piston gas compressor. Such 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 the compression chamber. The gaseous fuels are received and compressed in the compression chamber.

[0004] The reciprocating piston gas compressors further comprise a sliding seal at an interface between the piston and the cylinder. However, the sliding seal may not be 100% leak proof and exhibit some minor leakage referred to as blowby gas. Therefore, fluids, such as the gaseous fuels, may leak from a high pressure (i.e., the compression chamber) towards a low pressure (i.e., the driving chamber).

[0005] In some cases, the piston of the reciprocating piston gas compressor may be driven by drive mechanisms, such as a hydraulic drive mechanism. In floating-piston-type reciprocatingpiston gas compressors, the hydraulic drive mechanism may use a hydraulic fluid in the driving chamber. Since the hydraulic fluid may remain at a higher pressure than the gaseous fuel, the gaseous fuel may not leak from the compression chamber to the driving chamber.

[0006] However, the hydraulic drive mechanism may have extremely poor efficiency. This may significantly increase parasitic losses of the reciprocating piston gas compressor and / or of the internal combustion engine comprising the reciprocating piston gas compressor.

[0007] The state of the art is therefore lacking in techniques for achieving a high efficiency while managing an internal gas leakage in a compressor (e.g., the reciprocating piston gas compressor). The present disclosure provides a compressor system comprising a compressor and a method for managing the internal gas leakage in the compressor of the compressor system.Summary

[0008] An improved compressor system is provided. The compressor system comprises a compressor, a storage vessel, and a control valve. The compressor comprises a cylinder comprising a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a piston rod extending through the second end of the cylinder and connecting with the piston, a piston-rod seal between the piston rod and the second end of the cylinder, a compression chamber defined between the first end and the piston, and a driving chamber defined between the piston and the second end. The compression chamber is configured to receive a gas therein. The storage vessel is disposed in fluid communication with the driving chamber. The storage vessel is configured to store the gas which leaks from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal. The control valve is disposed in fluid communication with the storage vessel and the compression chamber. The control valve is configured to control a flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

[0009] In an exemplary embodiment, the compressor includes a cylinder head at the second end, and a piston-rod channel in the cylinder head through which the piston rod extends. The storage vessel can be in fluid communication with the piston-rod channel and configured to store the gas which leaks from the driving chamber to the piston-rod channel. The driving chamber can be a compression chamber, and the gas can leak from the driving chamber to the piston-rod channel during a compression stroke in the driving chamber. The compressor can be a double-acting compressor, where the compression chamber compresses the gas during a first compression stroke and intakes gas during a first intake stroke, and the driving chamber compresses the gas during a second compression stroke and intakes the gas during a second intake stroke. The cylinder headcan further include a fluid communication channel extending from the piston-rod channel to an outer surface of the compressor. There can be a first conduit fluidly communicating the piston-rod channel with the storage vessel, and a second conduit fluidly communicating the storage vessel with the control valve; and a third conduit fluidly communicating the control valve with the compression chamber.

[0010] In an exemplary embodiment, the control valve can be a three-way valve, where the three-way valve can be further configured to control a flow of the gas from a gas supply to the compression chamber. There can be a first conduit fluidly communicating the driving chamber with the storage vessel; a second conduit fluidly communicating the storage vessel with the control valve; and a third conduit fluidly communicating the control valve with the compression chamber.

[0011] The control valve can be an electronically controlled valve configured to open when a pressure of the gas within the storage vessel is greater than an upper threshold pressure, thereby allowing the flow of the gas from the storage vessel to the compression chamber. The electronically controlled valve can further be configured to close when a pressure of the gas within the storage vessel is less than a lower threshold pressure, thereby preventing the flow of the gas from the storage vessel to the compression chamber.

[0012] A controller communicably can be coupled to the control valve, where the controller can be configured to open the control valve when a pressure of the gas within the storage vessel is greater than an upper threshold pressure, thereby allowing the flow of the gas from the storage vessel to the compression chamber; and close the control valve when a pressure of the gas within the storage vessel is less than a lower threshold pressure, thereby preventing the flow of the gas from the storage vessel to the compression chamber.

[0013] There can be a piston rod attached to the piston and extending through the cylinder at the second end. A seal can be disposed between the piston rod and the cylinder at the second end. A piston seal can be disposed between the piston and the cylinder.

[0014] An improved method for recycling a gas in a compressor is provided. The compressor comprises a cylinder having a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a piston rod extending through the second end of the cylinder and connecting with the piston, a piston-rod seal between the piston rod and the second end of thecylinder, a compression chamber defined between the first end and the piston, and a driving chamber defined between the piston and the second end. The method comprises receiving the gas leaked from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal within a storage vessel. The method further comprises controlling, via a control valve, a flow of the gas from the storage vessel to the compression chamber of from the storage vessel to the driving chamber.

[0015] Controlling the flow of the gas can further include allowing the flow of the gas from the storage vessel to the compression chamber of from the storage vessel to the driving chamber when a pressure of the gas within the storage vessel is greater than an upper threshold pressure. Controlling the flow of the gas can further include preventing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber when a pressure of the gas within the storage vessel is less than a lower threshold pressure. Controlling the flow of the gas can further include opening the control valve, via a controller, when the pressure of the gas within the storage vessel is greater than the upper threshold pressure, thereby allowing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber; and closing the control valve, via the controller, when the pressure of the gas within the storage vessel is less than the lower threshold pressure, thereby preventing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber. When the control valve is a three-way valve, the method can further include controlling, via the three-way valve, a flow of the gas from a gas supply to the compression chamber.

[0016] An improved compressor system for an internal combustion engine having an intake manifold is provided. The compressor system comprises a compressor and an injector. The compressor comprises a cylinder comprising a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a piston rod extending through the second end of the cylinder and connecting with the piston, a piston-rod seal between the piston rod and the second end of the cylinder, a compression chamber defined between the first end and the piston, and a driving chamber defined between the piston and the second end, the piston rod extending through the driving chamber from the second end to the piston. The compression chamber is configured to receive a gas therein. The injector is disposed in fluid communication with the driving chamber and extends into the intake manifold. The injector is configured to receive the gas which leaksfrom the compression chamber to the driving chamber or from the driving chamber past the piston- rod seal and inject the gas into the intake manifold.

[0017] In an exemplary embodiment, the improved compressor system includes a cylinder head at the second end of the cylinder, and a piston-rod channel in the cylinder head through which the piston rod extends. A regulator can be fluidly disposed between the piston-rod channel and the injector, and the regulator can be configured to control a pressure of the gas supplied to the injector from the piston-rod channel

[0018] The compressor system can further include a regulator fluidly disposed between the driving chamber and the injector, where the regulator can be configured to control a pressure of the gas supplied to the injector from the driving chamber. There can be a first conduit fluidly communicating the driving chamber with the regulator; and a second conduit fluidly communicating the regulator with the injector. The injector can be a port fuel injector. A controller can be communicably coupled to the injector, where the controller can be configured to control the injector to inject the gas into the intake manifold.

[0019] An improved method for a compressor that supplies a gas to an internal combustion engine having an intake manifold is provided. The compressor comprises a cylinder having a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a piston rod extending through the second of the cylinder and connecting with the piston, a piston-rod seal between the piston rod and the second end of the cylinder, a compression chamber defined between the first end and the piston, and a driving chamber defined between the piston and the second end. The method comprises supplying the gas leaked from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal to an injector. The method further comprises injecting, via the injector, the gas into the intake manifold of the internal combustion engine.

[0020] Supplying the gas can further include controlling, via a regulator, a pressure of the gas supplied to the injector from the driving chamber. Injecting the gas into the intake manifold of the internal combustion engine can further include controlling the injector, via a controller, to inject the gas into the intake manifold.Brief Description of the Drawings

[0021] FIG. 1A is a schematic diagram view illustrating a compressor system comprising a compressor, a storage vessel, and a control valve, according to an embodiment of the present disclosure;

[0022] FIG. IB is a schematic diagram view illustrating the compressor system of FIG. 1A having a different valve arrangement, according to an embodiment of the present disclosure;

[0023] FIG. 1C is a schematic diagram view illustrating the compressor system of FIG. 1A having a different valve arrangement, according to an embodiment of the present disclosure;

[0024] FIG. 2 is an exemplary plot depicting a pressure of a gas within the storage vessel of the compressor system;

[0025] FIG. 3 is a schematic diagram view illustrating a compressor system comprising the compressor and an injector, according to another embodiment of the present disclosure;

[0026] FIG. 4 is a flowchart view illustrating a method for recycling the gas in the compressor of the compressor system of FIG. 1A, according to an embodiment of the present disclosure; and

[0027] FIG. 5 is a flowchart view illustrating a method for the compressor of the compressor system of FIG. 3, according to an embodiment of the present disclosure.

[0028] FIG. 6 is a schematic diagram view illustrating a compressor according to a second embodiment that can be employed in the compressor systems of FIGS. 1A, IB, 1C, and 3.Detailed Description

[0029] In the present disclosure, it should be noted that the terms “right”, “left”, “inner”, “outer”, etc. indicate the position or positional relationship based on the position or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have aspecific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms “first,” “second,” and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. As used herein, the term “or” is an inclusive “or” operator and is equivalent to the term “and / or,” unless the context clearly dictates otherwise. In addition, throughout the specification, the meaning of “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.

[0030] Referring to FIG. 1A, 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 510 (shown in FIG. 3).

[0031] The compressor system 100 comprises a compressor 200. The compressor 200 comprises a cylinder 210 comprising a first end 212 and a second end 214 opposite to the first end 212. The compressor 200 further comprises a piston 220 slidably disposed within the cylinder 210. The piston 220 is movable within the cylinder 210. Particularly, the piston 220 is reciprocable within the cylinder 210. In some embodiments, the compressor 200 may use a drive mechanism 228 for driving or reciprocating the piston 220. In some embodiments, the drive mechanism 228 may comprise a hydraulic motor, an electrical motor, mechanical levers, gears, etc. In some embodiments, the hydraulic motor may be driven by a hydraulic pump, such as a fixed displacement hydraulic pump or a variable displacement hydraulic pump. In some embodiments, the electrical motor may be a variable speed motor or a single speed motor, based on desired application attributes. In the illustrated embodiment of FIG. 1A, the piston 220 is moving towards the first end 212 within the cylinder 210 as shown by an arrow DI.

[0032] The compressor 200 further comprises a compression chamber 230 defined between the first end 212 and the piston 220. The compressor 200 further comprises a driving chamber 240 defined between the piston 220 and the second end 214.

[0033] The compression chamber 230 is configured to receive a gas 310 therein. In the illustrated embodiment of FIG. 1A, the compression chamber 230 is configured to receive the gas310 from a gas supply 420. In some embodiments, the gas 310 may serve as a main fuel for the internal combustion engine 510 (shown in FIG. 3). In some embodiments, the gas 310 is selected from the group consisting of biogas, natural gas, hydrogen, and mixtures thereof. The gas supply 420 may therefore comprise a main fuel storage tank that may store a gaseous fuel as a compressed gas. As used herein, a gaseous fuel is any fuel in the gas state / phase at standard temperature and pressure, which in the context of this application is defined as a temperature of zero (0) degrees Celsius (°C) and an absolute pressure of one hundred (100) kilopascals (kPa). The compressor 200 can be configured to increase a pressure of the gas 310, such as when a pressure of the gas in gas supply 420 decreases below a threshold value. In some embodiments, the compressor 200 is configured to increase the pressure to a required injection pressure or greater.

[0034] In some embodiments, the compressor 200 further comprises a piston rod 222 attached to the piston 220 and extending through the cylinder 210 at the second end 214. The piston rod 222 is configured to connect the piston 220 to the drive mechanism 228.

[0035] The driving chamber 240 may further comprise a low-pressure fluid 229 (e.g., a gas) therein. The low-pressure fluid 229 in the driving chamber 240 has a pressure less than a pressure of the gas 310 in the compression chamber 230. In some cases, during the operation of the compressor 200, there may be a leakage LI of the gas 310 from the compression chamber 230 to the driving chamber 240 due to a pressure differential. Constituents of the low-pressure fluid 229 may change over time. For example, when the compressor 200 begins operation, such as for a first time or after a long time, the low-pressure fluid 229 may be air, but as compressor 200 operates and the leakage LI continues to accumulate in the driving chamber 240, the low-pressure fluid 229 comprises more and more of the gas 310 than air over time, where in the limit there may be negligible or no air remaining in the driving chamber 240 as the low-pressure fluid 229 is processed, as will be discussed in detail below.

[0036] In some embodiments, the compressor 200 further comprises a piston seal 226 disposed between the piston 220 and the cylinder 210. The piston seal 226 may substantially reduce the leakage LI of the gas 310 from the compression chamber 230 to the driving chamber 240. However, the piston seal 226 may not be 100% leak proof and still exhibit some minor leakage.

[0037] A substantial amount of the gas 310 leaked into the driving chamber 240 may build-up a substantial amount of pressure in the driving chamber 240. This may lead to a leakage L2 of the gas 310 from the driving chamber 240 into an environment of the compressor system 100 or the atmosphere. This may be highly undesirable.

[0038] In some embodiments, the compressor 200 further comprises a seal 224 disposed between the piston rod 222 and the cylinder 210 at the second end 214 to prevent the leakage L2 of the gas 310 from the driving chamber into the environment of the compressor system 100 or the atmosphere. However, the seal 224 may also not be 100% leak proof and exhibit some minor leakage.

[0039] The compressor system 100 further comprises a storage vessel 300 disposed in fluid communication with the driving chamber 240. The storage vessel 300 is configured to store the gas 310 which leaks from the compression chamber 230 to the driving chamber 240. This may delay and preferably prevent the build-up of the substantial amount of pressure in the driving chamber 240, which may otherwise lead to the leakage L2 of the gas 310 from the driving chamber 240 into the environment of the compressor system 100 or the atmosphere.

[0040] The compressor system 100 further comprises a control valve 400 disposed in fluid communication with the storage vessel 300 and the compression chamber 230. The control valve 400 is configured to control a flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230. In some embodiments, the control valve 400 is an electronically controlled valve, such as a solenoid valve. The control valve 400 may be hereinafter interchangeably referred to as “the electronically controlled valve 400”. In the illustrated embodiment of FIG. 1A, the control valve 400 is a two-way valve 405.

[0041] In some embodiments, the compressor system 100 further comprises a controller 450 communicably coupled to the control valve 400. In some embodiments, the controller 450 is an electronic controller such as a computer comprising a processor and 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 other embodiments, the controller 450 may be an engine control unit (ECU) of the internal combustion engine 510 (shown in FIG. 3). In some embodiments, the controller 450 may further be communicably coupled to the drive mechanism228. The controller 450 may be configured to control one or more components of the drive mechanism 228, for example, the hydraulic fluid flow from the hydraulic pump or the electrical motor.

[0042] In some embodiments, the compressor system 100 further comprises a first conduit 250 fluidly communicating the driving chamber 240 with the storage vessel 300. In some embodiments, the compressor system 100 further comprises a second conduit 260 fluidly communicating the storage vessel 300 with the control valve 400. In some embodiments, the compressor system 100 further comprises a third conduit 270 fluidly communicating the control valve 400 with the compression chamber 230.

[0043] In some embodiments, the compressor system 100 further comprises one or more check valves. In the illustrated embodiment of FIG. 1, the third conduit 270 comprises a one-way check valve 424 that allows a unidirectional flow of the gas 310 into the compression chamber 230. In other words, the check valve 424 may ensure that the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230 is unidirectional. In some embodiments, the compressor system 100 further comprises another one-way check valve 426 that allows a unidirectional flow of the gas 310 from the gas supply 420 into the compression chamber 230. In other words, the check valve 426 may ensure that a flow 422 of the gas 310 from the gas supply 420 to the compression chamber 230 is unidirectional.

[0044] Referring to FIG. IB, there is shown the compressor system 101, 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. The compressor system 101 shown in FIG. IB is substantially similar and functionally equivalent to the compressor system 100 illustrated in FIG. 1A. However, the compressor system 101 shown in FIG. IB has a different control valve 400. Specifically, in the illustrated embodiment of FIG. IB, the control valve 400 is athree-way valve 410. The three-way valve 410 is configured to control the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230. In addition, the three- way valve 410 is configured to control the flow 422 of the gas 310 from the gas supply 420 to the compression chamber 230. In such embodiments, the controller 450 may be configured to control the three-way valve 410 to control the flow 422 of the gas 310 from the gas supply 420 to the compression chamber 230. In some embodiments, the controller 450 may simultaneously fluidlydisconnect, or fluidly isolate, the storage vessel 300 and the gas supply 420 from the compression chamber 230.

[0045] Referring to FIG. 1C, there is shown the compressor system 102, according to another embodiment of the present disclosure. The compressor system 102 shown in FIG. 1C is substantially similar and functionally equivalent to the compressor system 100 illustrated in FIG. 1A. However, the compressor system 102 shown in FIG. 1C has an additional control valve. Specifically, in the illustrated embodiment of FIG. 1C, the compressor system 102 further comprises a two-way valve 430 configured to control the flow 422 of the gas 310 from the gas supply 420 to the compression chamber 230. In some embodiments, the two-way valve 430 is communicably coupled to the controller 450. In such embodiments, the controller 450 may be configured to control the two-way valve 430 to control the flow 422 of the gas 310 from the gas supply 420 to the compression chamber 230.

[0046] FIG. 2 is an exemplary plot 460 depicting a pressure 302 of the gas 310 within the storage vessel 300 (shown in FIG. 1A) versus time. The pressure 302 is expressed in arbitrary units (a.u.) in the ordinate. Time is expressed in arbitrary units (a.u.) in abscissa. It should be noted that a static or an average pressure is the same in the storage vessel 300 and the driving chamber 240, although a dynamic or an instantaneous pressure may vary as mass is leaked into the driving chamber 240 and as the gas 310 is let out of the storage vessel 300 through the control valve 400.

[0047] Referring to FIGS. 1 A, IB, 1C, and 2, the control valve 400 is configured to open when the pressure 302 of the gas 310 within the storage vessel 300 is greater than an upper threshold pressure 304, thereby allowing the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230. Specifically, the electronically controlled valve 400 is configured to open when the pressure 302 of the gas 310 within the storage vessel 300 is greater than the upper threshold pressure 304. In this manner, gas 310 can be drawn into compression chamber 230 during an intake stroke of compressor 200. In some embodiments, the controller 450 is configured to the open the control valve 400 when the pressure 302 of the gas 310 within the storage vessel 300 is greater than the upper threshold pressure 304, thereby allowing the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230. It is understood by those familiar with the technology, that in FIG. 1A the flow 312 of the gas 310 from the storage vessel 300 canonly occur when the pressure 302 is greater than a pressure of the gas 310 in the gas supply 420 (particularly when the check valves 424 and 426 have the same cracking pressure). Therefore, the gas 310 may be re-compressed in the compression chamber 230 of the compressor 200 and may be delivered to the internal combustion engine 510 (shown in FIG. 3). The compressor systems 100, 101, 102 may thus allow consumption of the gas 310 leaked from the compression chamber 230 to the driving chamber 240 and prevent the build-up of the substantial amount of pressure in the driving chamber 240, which may otherwise lead to the leakage L2 of the gas 310 from the driving chamber 240 into the environment of the compressor systems 100, 101, 102.

[0048] Further, the control valve 400 is configured to close when the pressure 302 of the gas 310 within the storage vessel 300 is less than a lower threshold pressure 306, thereby preventing the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230. Specifically, the electronically controlled valve 400 is configured to close when the pressure 302 of the gas 310 within the storage vessel 300 is less than the lower threshold pressure 306. In some embodiments, the controller 450 is configured to close the control valve 400 when the pressure 302 of the gas 310 within the storage vessel 300 is less than the lower threshold pressure 306, thereby preventing the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230. The lower threshold pressure 306 may be a minimum pressure required to reintroduce the gas 310 from the storage vessel 300 into the compression chamber 230. In some embodiments, like the gas compressor system 100 in FIG. 1A, a value of the lower threshold pressure 306 may decrease over time as a pressure in the gas supply 420 decreases. Therefore, a pressure of the gas 310 inside the storage vessel 300 is only reduced till the lower threshold pressure 306.

[0049] As is apparent from the plot 460, when the pressure 302 of the gas 310 within the storage vessel 300 increases from greater than the lower threshold pressure 306 and less than the upper threshold pressure 304, the gas 310 is stored within the storage vessel 300. In other words, when the pressure 302 of the gas 310 within the storage vessel 300 increases greater than the lower threshold pressure 306 and less than the upper threshold pressure 304, the gas 310 is accumulated within the storage vessel 300. Further, when the pressure 302 of the gas 310 within the storage vessel 300 crosses or reaches the upper threshold pressure 304, the gas 310 is released from the storage vessel 300 to the compression chamber 230 via the control valve 400 till the pressure 302of the gas 310 within the storage vessel 300 crosses or reaches the lower threshold pressure 306. In other words, when the pressure 302 of the gas 310 within the storage vessel 300 crosses or reaches the upper threshold pressure 304, the gas 310 is re-introduced into the compression chamber 230 from the storage vessel 300 via the control valve 400 till the pressure 302 of the gas 310 within the storage vessel 300 crosses or reaches the lower threshold pressure 306.

[0050] Referring to FIG. 3, there is shown a compressor system 500. Specifically, FIG. 3 illustrates a schematic diagram of the compressor system 500 for the internal combustion engine 510 having an intake manifold 520.

[0051] The compressor system 500 comprises the compressor 200. The compressor system 500 further comprises an injector 600 disposed in fluid communication with the driving chamber 240. In some embodiments, the injector 600 is a port fuel injector. In some embodiments, the injector 600 is a low-pressure port fuel injector. The injector 600 extends into the intake manifold 520. In some embodiments, the injector 600 extends at least partially into the intake manifold 520.

[0052] The inj ector 600 is configured to receive the gas 310 which leaks from the compression chamber 230 to the driving chamber 240. The injector 600 is further configured to inject the gas 310 into the intake manifold 520. Therefore, the compressor system 500 may fumigate the gas 310, which leaks from the compression chamber 230 to the driving chamber 240, into the intake manifold 520 from time to time. The gas 310 which is fumigated into the intake manifold 520 may be then consumed in the internal combustion engine 510. The compressor system 500 may therefore allow consumption of the gas 310 leaked from the compression chamber 230 to the driving chamber 240 and prevent the build-up of the substantial amount of pressure in the driving chamber 240, which may otherwise lead to the leakage L2 of the gas 310 from the driving chamber 240 into the environment of the compressor system 500.

[0053] In some embodiments, the compressor system 500 further comprises a controller 650 communicably coupled to the injector 600. The controller 650 is configured to control the injector 600 to inject the gas 310 into the intake manifold 520. For example, in some embodiments, the controller 650 may be configured to control an injection timing of the injector 600. The injection timing may be determined or may be predetermined responsive to operating conditions of theinternal combustion engine 510. The operating conditions may be determined from various measured parameters that may be provided to the controller 650.

[0054] In some embodiments, the controller 650 may be substantially similar to the controller 450 (shown in FIGS. 1A, IB, and 1C). In some embodiments, the controller 650 is an electronic controller such as a computer comprising a processor and 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 other embodiments, the controller 650 may be the ECU of the internal combustion engine 510. In some embodiments, the controller 650 may further be communicably coupled to the drive mechanism 228. The controller 650 may be configured to control one or more components of the drive mechanism 228, for example, the motor.

[0055] In some embodiments, the compressor system 500 further comprises a regulator 610 fluidly disposed between the driving chamber 240 and the injector 600. The regulator 610 is configured to control a pressure 502 of the gas 310 supplied to the injector 600 from the driving chamber 240. In some embodiments, the regulator 610 is an electronic pressure regulator. In such embodiments, the controller 650 may be communicably coupled to the regulator 610 and configured to control the regulator 610. In other embodiments, the regulator 610 is a mechanical pressure regulator.

[0056] In some embodiments, the compressor system 500 further comprises a first conduit 530 fluidly communicating the driving chamber 240 with the regulator 610. In some embodiments, the compressor system 500 further comprises a second conduit 540 fluidly communicating the regulator 610 with the injector 600.

[0057] Referring to FIG. 4, there is shown a flowchart illustrating a method 700 for recycling the gas 310 in the compressor 200 shown in FIGS. 1A, IB, 1C, according to an embodiment of the present disclosure.

[0058] The method 700 will be described with reference to FIGS. 1A, IB, 1C, and 2. The method 700 comprises the following steps:

[0059] At step 702, the method 700 comprises receiving the gas 310 leaked from the compression chamber 230 to the driving chamber 240 within the storage vessel 300.

[0060] At step 704, the method 700 comprises controlling, via the control valve 400, the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230.

[0061] In some embodiments, controlling the flow 312 of the gas 310 further comprises allowing or starting the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230 when the pressure 302 of the gas 310 within the storage vessel 300 is greater than the upper threshold pressure 304. In some embodiments, controlling the flow 312 of the gas 310 further comprises opening the control valve 400, via the controller 450, when the pressure 302 of the gas 310 within the storage vessel 300 is greater than the upper threshold pressure 304, thereby allowing or starting the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230.

[0062] In some embodiments, controlling the flow 312 of the gas 310 further comprises preventing or stopping the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230 when the pressure 302 of the gas 310 within the storage vessel 300 is less than the lower threshold pressure 306. In some embodiments, controlling the flow 312 of the gas 310 further comprises closing the control valve 400, via the controller 450, when the pressure 302 of the gas 310 within the storage vessel 300 is less than the lower threshold pressure 306, thereby preventing or stopping the flow 312 of the gas 310 from the storage vessel 300 to the compression chamber 230.

[0063] In some embodiments, the method 700 further comprises controlling, via the three-way valve 410, the flow 422 of the gas 310 from the gas supply 420 to the compression chamber 230.

[0064] Referring to FIG. 5, there is shown a flowchart illustrating a method 800 for the compressor 200 that supplies the gas 310 to the internal combustion engine 510 having the intake manifold 520 shown in FIG. 3, according to an embodiment of the present disclosure. The method 800 comprises the following steps:

[0065] At step 802, the method 800 comprises supplying the gas 310 leaked from the compression chamber 230 to the driving chamber 240 to the injector 600.

[0066] In some embodiments, supplying the gas 310 further comprises controlling, via the regulator 610, the pressure 502 of the gas 310 supplied to the injector 600 from the driving chamber 240.

[0067] At step 804, the method 800 comprises injecting, via the injector 600, the gas 310 into the intake manifold 520 of the internal combustion engine 510.

[0068] In some embodiments, inj ecting the gas 310 into the intake manifold 520 of the internal combustion engine 510 further comprises controlling the injector 600, via the controller 650, to inject the gas 310 into the intake manifold 520.

[0069] Referring to FIGS. 1A, IB, 1C, 2, 3, 4, and 5, the compressor systems 100, 101, 102, and 500 may therefore allow consumption of the gas 310 leaked from the compression chamber 230 to the driving chamber 240 and prevent the build-up of the substantial amount of pressure in the driving chamber 240, which may otherwise lead to the leakage L2 of the gas 310 from the driving chamber 240 into the environment of the compressor systems 100, 101, 102, and 500.

[0070] Referring now to FIG. 6, there is shown compressor 201 that is a double-acting compressor. In the illustrated embodiment, compressor 201 is a single stage compressor. In some embodiments, compressor 201 can be part of a multi-stage compressor. Compressor 201 includes chamber 230a and chamber 230b. A cycle of compressor 201 includes piston 220 moving from end 214 towards end 212 during a stroke, and when reaching end 212 reversing direction and moving back towards end 214 in another stroke. When piston 220 moves to the left towards end 212, chamber 230a is a compression chamber and compresses gas 310 therein while chamber 230b operates as an intake chamber and intakes gas 310 thereto from gas supply 420. When piston 220 moves to the left, the stroke of piston 220 is a compression stroke for chamber 230a and an intake stroke for chamber 230b. When piston 220 moves to the right towards end 214, chamber 230b is a compression chamber and compressors gas 310 therein while chamber 230a is an intake chamber and intakes gas 310 thereto from gas supply 420. When piston 220 moves to the right, the stroke of piston 220 is an intake stroke for chamber 230a and a compression stroke for chamber 230b. Chamber 230b can also be considered a driving chamber since piston rod 222 extends through chamber 230b to drive piston 220, during both strokes of the compressor cycle. Piston 220 is operating as a double acting piston since, when piston 220 moves to the left in the illustratedembodiment, piston side 221a compresses gas 310 in chamber 230a, and when piston 220 moves to the right, piston side 221b compresses gas 310 in chamber 230b. Each chamber 230a, 230b includes a respective inlet check valve (not shown) that opens when a pressure in the respective chamber 230a, 230b is less than a pressure in gas supply 420. Each chamber 230a, 230b includes a respective outlet check valve (not shown) that opens when a pressure in the respective chamber 230a, 230b is greater than a pressure downstream from the respective outlet check valve. Although not a requirement, typically the downstream sides of the outlet check valves are fluidly connected.

[0071] Leakage LI of the gas 310 from chamber 230a to chamber 230b may occur when the gas 310 is being compressed in chamber 230a. Leakage LI of the gas 310 from chamber 230b to chamber 230a may occur when the gas 310 is being compressed in chamber 230b. In both circumstances, leakage LI is leaking into a chamber (either chamber 230a or 230b) that will compress the gas 310 (including leakage LI) on a subsequent stroke of piston 220. In this regard, leakage LI is inherently processed by the operation of compressor 201.

[0072] When piston 220 is moving to the right in the illustrated embodiment, the pressure created in chamber 230b may cause leakage L2 of the gas 310 past seal 224 into piston-rod channel 910 in cylinder head 900. Seal 224 is a piston-rod seal between piston rod 222 and cylinder 210 at end 214, and more particularly in the illustrated embodiment between piston rod 222 and cylinder head 900. In some embodiments, the compressor 201 further includes a seal 920, and in particular an annular seal, disposed between the piston rod 222 and the cylinder head 900 at an end 930 of the cylinder head 900 to prevent the leakage L2 of the gas 310 from the piston-rod channel 910 into the environment of the compressor system or the atmosphere. However, the seal 920 may also not be 100% leak proof and exhibit some minor leakage if or when the pressure inside piston- rod channel 910 increases above a threshold. Fluid communication channel 940 in cylinder head 900 allows leakage L2 of the gas 310 in piston-rod channel 910 to be fluidly communicated to conduit 960 fluidly sealed with fluid communication channel 940. Fluid communication channel 940 extends from piston-rod channel 910 to an outer surface of compressor 201. In some embodiments, fluid communication channel 940 extends from piston-rod channel 910 to outer surface 950 of the cylinder head 900. In some embodiments, fluid communication channel 940 extends from piston-rod channel 910 to an outer surface of end 930 of cylinder head 900. Volume970 includes piston-rod channel 910 (between seals 224 and 920) and fluid communication channel 940.

[0073] Referring to both FIGS. 1A and 6, in some embodiments compressor system 100 (seen in FIG. 1A) can employ compressor 201 (seen in FIG. 6) instead of compressor 200 (seen in FIG.IA). In this circumstance, conduit 960 seen in FIG. 6 is part of first conduit 250 seen in FIG. 1A. The flow 312 of gas 310 from storage vessel 300 (seen in FIG. 1A) can fluidly supply the gas 310 from the storage vessel to chamber 230a during the intake stroke of chamber 230a and to chamber 230b during the intake stroke of chamber 230b.

[0074] Referring to both FIGS. IB and 6, in some embodiments compressor system 101 (seen in FIG. IB) can employ compressor 201 (seen in FIG. 6) instead of compressor 200 (seen in FIG.IB). In this circumstance, conduit 960 seen in FIG. 6 is part of first conduit 250 seen in FIG. IB. The flow 312 of gas 310 from storage vessel 300 (seen in FIG. IB) can fluidly supply the gas 310 from the storage vessel to chamber 230a during the intake stroke of chamber 230a and to chamber 230b during the intake stroke of chamber 230b.

[0075] Referring to both FIGS. 1C and 6, in some embodiments compressor system 101 (seen in FIG. 1C) can employ compressor 201 (seen in FIG. 6) instead of compressor 200 (seen in FIG.IC). In this circumstance, conduit 960 seen in FIG. 6 is part of first conduit 250 seen in FIG. 1C. The flow 312 of gas 310 from storage vessel 300 (seen in FIG. 1C) can fluidly supply the gas 310 from the storage vessel to chamber 230a during the intake stroke of chamber 230a and to chamber 230b during the intake stroke of chamber 230b.

[0076] Referring to both FIGS. 3 and 6, in some embodiments compressor system 500 (seen in FIG. 3) can employ compressor 201 (seen in FIG. 6) instead of compressor 200 (seen in FIG. 3). In this circumstance, conduit 960 seen in FIG. 6 is part of first conduit 530 seen in FIG. 3.

[0077] 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 compressor comprising: a cylinder comprising a first end and a second end opposing the first end; a piston slidably disposed within the cylinder; a piston rod extending through the second end of the cylinder and connecting with the piston; a piston-rod seal between the piston rod and the second end of the cylinder; a compression chamber defined between the first end and the piston, wherein the compression chamber is configured to receive a gas therein; and a driving chamber defined between the piston and the second end, the piston rod extending through the driving chamber from the second end to the piston; a storage vessel disposed in fluid communication with the compressor, wherein the storage vessel is configured to store the gas which leaks from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal; and a control valve disposed in fluid communication with the storage vessel and the compression chamber, wherein the control valve is configured to control a flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

2. The compressor system of claim 1, wherein the compressor further comprises a cylinder head at the second end, and a piston-rod channel in the cylinder head through which the piston rod extends, the storage vessel is in fluid communication with the piston-rod channel and configured to store the gas which leaks from the driving chamber to the piston-rod channel.

3. The compressor system of claim 2, wherein the driving chamber is a compression chamber, and the gas leaks from the driving chamber to the piston-rod channel during a compression stroke in the driving chamber.

4. The compressor system of claim 2, wherein the compressor is a double-acting compressor, the compression chamber compresses the gas during a first compression stroke and intakes gas during a first intake stroke, and the driving chamber compresses the gas during a second compression stroke and intakes the gas during a second intake stroke.

5. The compressor system of claim 2, wherein the cylinder head further comprises a fluid communication channel extending from the piston-rod channel to an outer surface of the compressor.

6. The compressor system of claim 2, further comprising: a first conduit fluidly communicating the piston-rod channel with the storage vessel; a second conduit fluidly communicating the storage vessel with the control valve; and a third conduit fluidly communicating the control valve with the compression chamber.

7. The compressor system of claim 1, wherein the storage vessel is in fluid communication with the driving chamber and configured to store the gas which leaks from the compression chamber to the driving chamber.

8. The compressor system of claim 1, wherein the control valve is a three-way valve, wherein the three-way valve is further configured to control a flow of the gas from a gas supply to the compression chamber or from the gas supply to the driving chamber.

9. The compressor system of claim 1, further comprising: a first conduit fluidly communicating the driving chamber with the storage vessel;a second conduit fluidly communicating the storage vessel with the control valve; and a third conduit fluidly communicating the control valve with the compression chamber.

10. The compressor system of claim 1, wherein the control valve is an electronically controlled valve configured to open when a pressure of the gas within the storage vessel is greater than an upper threshold pressure, thereby allowing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

11. The compressor system of claim 10, wherein the electronically controlled valve is further configured to close when a pressure of the gas within the storage vessel is less than a lower threshold pressure, thereby preventing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

12. The compressor system of claim 1, further comprising a controller communicably coupled to the control valve, wherein the controller is configured to: open the control valve when a pressure of the gas within the storage vessel is greater than an upper threshold pressure, thereby allowing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber; and close the control valve when a pressure of the gas within the storage vessel is less than a lower threshold pressure, thereby preventing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

13. The compressor system of claim 1, wherein the compressor further comprises a piston seal disposed between the piston and the cylinder.

14. A method for recycling a gas in a compressor that comprises a cylinder having a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a piston rod extending through the second end of the cylinder and connecting with the piston, a piston-rod seal between the piston rod and the second end of the cylinder, a compression chamber defined betweenthe first end and the piston, and a driving chamber defined between the piston and the second end, the method comprising: receiving the gas leaked from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal within a storage vessel; and controlling, via a control valve, a flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

15. The method of claim 14, wherein controlling the flow of the gas further comprises allowing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber when a pressure of the gas within the storage vessel is greater than an upper threshold pressure.

16. The method of claim 15, wherein controlling the flow of the gas further comprises preventing the flow of the gas from the storage vessel to the compression chamber of from the storage vessel to the driving chamber when a pressure of the gas within the storage vessel is less than a lower threshold pressure.

17. The method of claim 16, wherein controlling the flow of the gas further comprises: opening the control valve, via a controller, when the pressure of the gas within the storage vessel is greater than the upper threshold pressure, thereby allowing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber; and closing the control valve, via the controller, when the pressure of the gas within the storage vessel is less than the lower threshold pressure, thereby preventing the flow of the gas from the storage vessel to the compression chamber or from the storage vessel to the driving chamber.

18. The method of claim 14, wherein the control valve is a three-way valve, the method further comprising controlling, via the three-way valve, a flow of the gas from a gas supply to the compression chamber or from a gas supply to the driving chamber.

19. A compressor system for an internal combustion engine having an intake manifold, the compressor system comprising: a compressor comprising: a cylinder comprising a first end and a second end opposing the first end; a piston slidably disposed within the cylinder; a piston rod extending through the second end of the cylinder and connecting with the piston; a piston-rod seal between the piston rod and the second end of the cylinder; a compression chamber defined between the first end and the piston, wherein the compression chamber is configured to receive a gas therein; and a driving chamber defined between the piston and the second end, the piston rod extending through the driving chamber from the second end to the piston; and an injector disposed in fluid communication with the driving chamber and extending into the intake manifold, wherein the injector is configured to receive the gas which leaks from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal and inject the gas into the intake manifold.

20. The compressor system of claim 1, wherein the compressor further comprises a cylinder head at the second end, and a piston-rod channel in the cylinder head through which the piston rod extends.

21. The compressor system of claim 20, further comprising a regulator fluidly disposed between the piston-rod channel and the injector, wherein the regulator is configured to control a pressure of the gas supplied to the injector from the piston-rod channel.

22. The compressor system of claim 19, further comprising a regulator fluidly disposed between the driving chamber and the injector, wherein the regulator is configured to control a pressure of the gas supplied to the injector from the driving chamber.

23. The compressor system of claim 22, further comprising: a first conduit fluidly communicating the driving chamber with the regulator; and a second conduit fluidly communicating the regulator with the injector.

24. The compressor system of claim 19, wherein the injector is a port fuel injector.

25. The compressor system of claim 19, wherein the compressor further comprises a piston seal disposed between the piston and the cylinder.

26. The compressor system of claim 19, further comprising a controller communicably coupled to the injector, wherein the controller is configured to control the injector to inject the gas into the intake manifold.

27. A method for a compressor that supplies a gas to an internal combustion engine having an intake manifold, the compressor that comprises a cylinder having a first end and a second end opposing the first end, a piston slidably disposed within the cylinder, a piston rod extending through the second end of the cylinder and connecting with the piston, a piston-rod seal between the piston rod and the second end of the cylinder, a compression chamber defined between the first end and the piston, and a driving chamber defined between the piston and the second end, the piston rod extending through the driving chamber, the method comprising: supplying the gas leaked from the compression chamber to the driving chamber or from the driving chamber past the piston-rod seal to an injector; and injecting, via the injector, the gas into the intake manifold of the internal combustion engine.

28. The method of claim 27, wherein supplying the gas further comprises controlling, via a regulator, a pressure of the gas supplied to the injector.

29. The method of claim 27, wherein injecting the gas into the intake manifold of the internal combustion engine further comprises controlling the injector, via a controller, to inject the gas into the intake manifold.

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