US20230119867A1

US20230119867A1 - Pollution control system for diesel engine

Info

Publication number: US20230119867A1
Application number: US17/960,483
Authority: US
Inventors: Serge V. Monros
Original assignee: SVMTECH LLC
Current assignee: SVMTECH LLC
Priority date: 2021-10-19
Filing date: 2022-10-05
Publication date: 2023-04-20

Abstract

A pollution control system for a diesel engine includes a PCV valve and an associated vacuum pump having an inlet and an outlet adapted to vent blow-by gas out from a crankcase to an intake manifold on the diesel engine. The vacuum pump associated with the PCV valve selectively modulates vacuum pressure to adjustably increase or decrease a fluid flow rate of blow-by gas venting from the crankcase through the PCV valve.

Description

RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 63/257,510, filed on Oct. 19, 2021.

BACKGROUND OF THE INVENTION

The present invention generally relates to a system for controlling pollution in a diesel engine. More particularly, the present invention relates to a system that systematically controls a positive crankcase ventilation (PCV) valve assembly combined with a vacuum pump in a diesel engine designed to recycle engine fuel by-products, reduce emissions and improve engine performance.
As part of an effort to combat smog in the Los Angeles basin, California started requiring emission control systems on all model cars starting in the 1960's. The Federal Government extended these emission control regulations nationwide in 1968. Congress passed the Clear Air Act in 1970 and established the Environmental Protection Agency (EPA). Since then, vehicle manufacturers have had to meet a series of graduated emission control standards for the production and maintenance of vehicles. This involved implementing devices to control engine functions and diagnose engine problems. More specifically, automobile manufacturers started integrating electrically controlled components, such as electric fuel feeds and ignition systems. Sensors were also added to measure engine efficiency, system performance and pollution. These sensors were capable of being accessed for early diagnostic assistance.
On-Board Diagnostics (OBD) refers to early vehicle self-diagnostic systems and reporting capabilities. OBD systems provide current state information for various vehicle subsystems. The quantity of diagnostic information available via OBD has varied widely since the introduction of on-board computers to automobiles in the early 1980's. OBD originally illuminated a malfunction indicator light (MIL) for a detected problem, but did not provide information regarding the nature of the problem. Modern OBD implementations use a standardized fast digital communications port to provide real-time data in combination with standardized series of diagnostic trouble codes (DTCs) to establish rapid identification of malfunctions and the corresponding remedy from within the vehicle.
The California Air Resources Board (CARB or simply ARB) developed regulations to enforce the application of the first incarnation of OBD (known now as “OBD-I”). The aim of CARB was to encourage automobile manufacturers to design reliable emission control systems. CARB envisioned lowering vehicle emissions in California by denying registration of vehicles that did not pass the CARB vehicle emission standards. Unfortunately, OBD-I did not succeed at the time as the infrastructure for testing and reporting emissions-specific diagnostic information was not standardized or widely accepted. Technical difficulties in obtaining standardized and reliable emission information from all vehicles led to an inability to effectively implement an annual testing program.
OBD became more sophisticated after the initial implementation of OBD-I. OBD-II was a new standard introduced in the mid 1990's that implemented a new set of standards and practices developed by the Society of Automotive Engineers (SAE). These standards were eventually adopted by the EPA and CARB. OBD-II incorporates enhanced features that provide better engine monitoring technologies. OBD-II also monitors chassis parts, body and accessory devices, and includes an automobile diagnostic control network. OBD-II improved upon OBD-I in both capability and standardization. OBD-II specifies the type of diagnostic connector, pin configuration, electrical signaling protocols, messaging format and provides an extensible list of DTCs. OBD-II also monitors a specific list of vehicle parameters and encodes performance data for each of those parameters. Thus, a single device can query the on-board computer(s) in any vehicle. This simplification of reporting diagnostic data led to the feasibility of the comprehensive emissions testing program envisioned by CARB.
In fossil fuel burning engines, the combustion chamber is largely sealed off from the crankcase by a set of piston rings that are disposed around an outer diameter of the pistons within the piston cylinder. This keeps the oil in the crankcase rather than allowing it to burn as part of the combustion stroke, as in a two-stroke engine. Unfortunately, the piston rings are unable to completely seal off the piston cylinder. Consequently, crankcase oil intended to lubricate the cylinder is, instead, drawn into the combustion chamber and burned during the combustion process. Additionally, combustion waste gases comprising unburned fuel and exhaust gases in the cylinder simultaneously pass the piston rings and enter the crankcase. The waste gas entering the crankcase is commonly called “blow-by” or “blow-by gas”. Blow-by gases mainly consist of contaminants such as hydrocarbons (unburned fuel), carbon dioxide or water vapor, all of which are harmful to the engine crankcase.
The basic operation of a standard diesel engine varies somewhat based on the type of combustion process, the quantity of cylinders and the desired use/functionality. But regardless of the specific type of diesel engine, it is well known that such engines suffer the occurrence of blow-by gases that pass from the combustion chamber, past the piston ring, and into the engine crankcase. Such blow-by gases evidence an inefficiency in the degree of combustion of the diesel fuel. The blow-by gases also gum up the engine block and can dirty the engine oil, reducing performance and shortening the life of the engine.
While prior art systems exist for recovering and recycling blow-by gases, none have previously worked well with diesel engines. Specifically, such prior art blow-by gas systems utilized a PCV valve connecting the crankcase to the combustion chamber intake. Systems utilizing a PCV valve require positive crankcase pressure (or a vacuum on the engine intake) to force the blow-by gases through the PCV valve. Without such positive pressure in the crankcase, the spring-biased PCV valve will not open up to allow the blow-by gases to flow from the crankcase.
The quantity of blow-by gas in the crankcase can be several times that of the concentration of hydrocarbons in the intake manifold. Simply venting these gases to the atmosphere increases air pollution. Although, trapping the blow-by gases in the crankcase allows the contaminants to condense out of air and accumulate therein over time. Condensed contaminants form corrosive acids and sludge in the interior of the crankcase that dilutes the lubricating oil. This decreases the ability of the oil to lubricate the cylinder and crankshaft.
Degraded oil that fails to properly lubricate the crankcase components (e.g. the crankshaft and connecting rods) can be a factor in poor engine performance. Inadequate crankcase lubrication contributes to unnecessary wear on the piston rings which simultaneously reduces the quality of the seal between the combustion chamber and the crankcase. As the engine ages, the gaps between the piston rings and cylinder walls increase resulting in larger quantities of blow-by gases entering the crankcase. Too much blow-by gases entering the crankcase can cause power loss and even engine failure. Moreover, condensed water in the blow-by gases can cause engine parts to rust. Hence, crankcase ventilation systems were developed to remedy the existence of blow-by gases in the crankcase.
In general, crankcase ventilation systems in gasoline engines expel blow-by gases through a positive crankcase ventilation (PCV) valve so as to recirculate (i.e. vent) blow-by gases from the crankcase back into the intake manifold to be burned again with a fresh supply of air/fuel during combustion. This is particularly desirable as the harmful blow-by gases are not simply vented to the atmosphere. A crankcase ventilation system should also be designed to limit, or ideally eliminate, blow-by gas in the crankcase to keep the crankcase as clean as possible. Early PCV valves comprised simple one-way check valves. These PCV valves relied solely on pressure differentials between the crankcase and intake manifold to function correctly. When a piston travels downward during intake, the air pressure in the intake manifold becomes lower than the surrounding ambient atmosphere. This result is commonly called “engine vacuum”. The vacuum draws air toward the intake manifold. However, diesel engines do not operate with positive crankcase pressure, so typical PCV valves on their own do not work well with diesel engines.
Accordingly, the blow-by gases in diesel engines are not readily drawn from the crankcase and into the intake manifold through a PCV valve that provides a conduit therebetween. A PCV valve basically opens a one-way path for blow-by gases to vent from the crankcase back into the intake manifold. When the pressure difference changes (i.e. the pressure in the intake manifold becomes relatively higher than the pressure in the crankcase), the PCV valve closes and prevents gases from exiting the intake manifold and entering the crankcase. Hence, the PCV valve is a “positive” crankcase ventilation system, wherein gases are only allowed to flow in one direction—out from the crankcase and into the intake manifold. The one-way check valve is basically an all-or-nothing valve. That is, the valve is completely open during periods when the pressure on the intake manifold side is relatively less than the pressure on the crankcase side. Alternatively, the valve is completely closed when the pressure on the crankcase side is relatively lower than the pressure on the intake manifold side. Thus, a diesel engine that does not operate with a vacuum on the combustion side can never have a higher pressure on the crankcase side that it does on the intake manifold side, i.e., positive pressure in the crankcase. Even the improved PCV valve designs that improve over the basic one-way check valve, i.e., using a spring to position an internal restrictor, don't work with diesel engines for the same reason—no pressure differential.
Thus, there exists a significant need for an improved PCV valve system that optimally regulates the flow of engine blow-by gases from the crankcase to the intake manifold in diesel engines. Such a PCV valve system should decrease the rate of fuel consumption, decrease the rate of harmful pollutant emissions, and increase engine performance. The present invention fulfills these needs and provides further related advantages.

SUMMARY OF THE INVENTION

The pollution control system for a diesel engine disclosed herein includes a PCV valve having an inlet and an outlet adapted to vent blow-by gas out from the crankcase to the intake manifold a diesel engine. More particularly, the PCV valve has an inlet fluidly connected to a crankcase on the diesel engine. The outlet of the PCV valve is fluidly connected to an intake manifold on the diesel engine.
A vacuum pump is associated with the PCV valve. The vacuum pump lessens vacuum pressure on the intake manifold side during periods of decreased blow-by gas production to decrease the fluid flow rate through the PCV valve. The vacuum pump increases vacuum pressure on the intake manifold side during periods of increased blow-by gas production to increase the fluid flow rate through the PCV valve. Typically, the vacuum pump is fluidly disposed between the PCV valve and the intake manifold.
A controller selectively operates the vacuum pump to increase vacuum pressure on an intake manifold side of the PCV valve relative to a pressure on a crankcase side of the PCV valve based, in part, on measurements from an engine sensor. The controller may operate the vacuum pump in real-time. The engine sensor may comprise at least one of an engine temperature sensor, an accelerometer sensor, an exhaust sensor, a batter sensor, a PCV valve sensor, a cam position sensor and/or an engine RPM sensor. In a particularly preferred embodiment, the engine sensor comprises at least a cam position sensor to determine RPMs of the engine.
An exhaust diverter may be fluidly connected to an exhaust outlet on the diesel engine to the intake manifold. The controller selectively operates the exhaust diverter to divert a portion of the exhaust gasses from the exhaust outlet to the intake manifold based, in part, on measurements from an exhaust analyzer.
The system may include an oil trap fluidly coupled to the PCV valve for condensing vaporized oil in the blow-by gas into liquid for re-use in the crankcase. Typically, the volume of the oil trap is relatively larger than a volume of a vent line carrying the blow-by gas to the oil trap from the crankcase. The oil trap may include an internal oil filter or separator. A drain line may be coupled to the oil trap for returning the liquid oil to the crankcase. The drain line may be coupled to the crankcase via a dip stick chamber. The vent line and the drain line may couple to different portions of the oil trap such that the vacuum drawing the blow-by gas through the oil trap does not interfere with the drainage of the liquid oil back into the crankcase.
Other features and advantages of the present invention will become apparent from the following more detailed description, when taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the invention. In such drawings:

FIG. 1 is a schematic illustrating a pollution control system having a controller operationally coupled to numerous sensors, a vacuum pump, a PCV valve, and an exhaust diverter in accordance with the invention;

FIG. 2 is a schematic illustrating a general configuration of the incorporation of the vacuum pump and PCV valve in a diesel engine in accordance with the invention;

FIG. 3 is a schematic illustrating a general configuration of the invention including an exhaust diverter in a diesel engine;

FIG. 4 is a schematic illustrating the general configuration of the vacuum pump and PCV valve, along with a blow-by gas oil trap in a diesel engine; and

FIG. 5 is a schematic cross-sectional view illustrating air flow and condensation of oil particles within an interior of an oil trap due to an oil filter or separator, in accordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in the drawings for purposes of illustration, the present invention for a pollution control system is referred to generally by the reference number 10. In FIG. 1 , the pollution control system 10 is generally illustrated as having a controller 12, may be mounted under a hood 14 of an automobile 16 having a diesel engine 36.
The controller 12 is electrically coupled to any one of a plurality of sensors that monitor and measure the real-time operating conditions and performance of the automobile 16. The controller 12 regulates the flow rate of blow-by gases by initiating an engine vacuum in a diesel engine through digital control of vacuum pump 17 and a PCV valve 18. The controller 12 may also regulate the operation of an exhaust diverter 19 for recycling emissions gases to the engine intake. The controller 12 receives real-time input from sensors that may include an engine temperature sensor 20, a cam position sensor 22, a battery sensor 24, a PCV valve sensor 26, an engine RPM sensor 28, an accelerometer sensor 30 and an exhaust sensor/analyzer 32. Data obtained from the sensors 20-32 by the controller 12 is used to regulate the PCV valve 18, as described in more detail below.
FIG. 2 is a schematic illustrating operation of the PCV valve 18 within the pollution control system 10. As shown in FIG. 2 , the vacuum pump 17 and PCV valve 18 are disposed between a crankcase 34, of an engine 36, and an intake manifold 38. In operation, the intake manifold 38 receives air an airline 42, which may originate from an air filter 44 processing an air intake line 46 to filter fresh air entering the pollution control system 10. Diesel fuel is introduced to the engine 36 from a fuel line 40 passing through a fuel injector 41 having a glow plug 41 a before mixing with the air from the intake manifold 38 in the piston cylinder 48.
As a piston 50 descends downward within the cylinder 48 from the top dead center, a combustion chamber 52 is opened. An input camshaft 54 is designed to open an input valve 56 thereby allowing air from the intake manifold 38 into the combustion chamber 52. At the appropriate time in the piston cycle, the injector 41, after proper heating by the glow plug 41 a, injects the fuel into the combustion chamber 52 where it is blended with the air. Conversely, the fuel/air mixture can be created and then heated by the glow plug 41 a together before being introduced into the combustion chamber 52.
The fuel/air mixture in the combustion chamber 52 is combusted through compression as is standard in a diesel engine. The rapid expansion of the combusted fuel/air in the combustion chamber 52 causes depression of the piston 50 within the cylinder 48. After combustion, an exhaust camshaft 60 opens an exhaust valve 62 to allow escape of the combustion gases from the combustion chamber 52 out an exhaust line 64.
Typically, during the combustion cycle, excess exhaust gases slip by a pair of piston rings 66 mounted in a head 68 of the piston 50. These “blow-by gases” enter the crankcase 34 due to the high pressure and temperature of combustion. Over time, harmful exhaust gases such as hydrocarbons, carbon monoxide, nitrous oxide and carbon dioxide can condense out from a gaseous state and coat the interior of the crankcase 34 and mix with the oil 70 that lubricates the mechanics within the crankcase 34. But, the pollution control system 10 is designed to vent these blow-by gases from the crankcase 34 to the intake manifold 38 to be recycled as fuel for the engine 36.
In a gasoline engine, prior art pollution control systems would accomplish the venting of blow-by gases from the crankcase by using a pressure differential between the crankcase and the intake manifold, as disclosed in U.S. Pat. No. 8,360,038. However, a diesel engine 36 does not operate using a pressure differential like a gasoline engine. Accordingly a different pollution control system 10 is needed to accomplish similar venting of blow-by gases from the crankcase 34. In the pollution control system 10, the crankcase 34 is connected to a vent 72 through a vent line 74 to an inlet on a PCV valve 18, the outlet of which is fluidly connected to the intake manifold 38 by recycle line 76.
In a typical gasoline engine, a PCV valve refers to a “Positive Crankcase Ventilation” valve. Because a diesel engine does not have the same pressure differential between the crankcase 34 and the intake manifold 36 the inventive pollution control system 10 requires another component. Specifically, a vacuum pump 17 is associated with the PCV valve 18, such as being inserted in the recycle line 76 between the PCV valve 18 and the intake manifold 38. As explained more fully below, the vacuum pump 17 artificially creates the pressure differential between the crankcase 34 side of the PCV valve 18 and the intake manifold 38 side of the PCV valve 18. Such a pressure differential does not ordinarily exist in a diesel engine 36.
In a particularly preferred embodiment, the pump 17 is very precise, i.e., a servo-controlled stepper pump motor having multiple steps per revolution for very precise control of the vacuum pressure. The system 10 is programmed to implement vacuum pressure in a diesel engine 36 to provide narrow tolerances in the drawing and recycling of blow-by gases from the crankcase 34. This servo-controlled stepper pump motor 17 can also be incorporated into a gasoline engine so as to provide improved control, better fuel economy, and reduced emissions. The vacuum pump preferably produces vacuum pressure in the range of 12-20 inches HgV. Ideally, the system is able to produce vacuum pressure of not less than 3 inches HgV.
Maintaining a certain vacuum pressure will depend on the engine load conditions, i.e., RPMs, torque, towing-weight, inclines, temperature, etc., for improving fuel efficiency or lowering emissions. The controller 12 is preferably pre-programmed with ideal vacuum pressure values for optimized performance under various load conditions. While the inventive system 10 is described specifically for diesel engines, the controller can be programmed for optimized performance of gasoline and other fuels.
In a particularly preferred embodiment, the servo stepper pump motor 17 is operated based on engine RPMs, which provides precise control of the vacuum pressure and the flow of the blow-by gases that go through the system 10. The engine RPMs may be measured accurately by using a cam position sensor 22 as disclosed above. This cam position sensor 22 is necessary to measure revolutions of the cam shaft as a diesel engine does not include spark plugs or similar ignition points that can be used to calculate RPMs. The cam position sensor 22 measures RPMs to help in determining engine load and necessary blow-by gas recycling. This will indicate when to activate or deactivate the vacuum pump 17 and PCV valve 18 to allow recycling of blow-by gases.
The vacuum pump 17 and PCV valve 18 may be manually adjusted or fully programmable. This precise control of the system 10 using vacuum pressure has been tested under different load conditions and for various exhaust gases, i.e., nitrous oxide, hydrocarbons, carbon or carbon dioxide, and particulate matter. The controller 12 may be programmed with an array or matrix of these measured vacuum pressure values determined by these tests for diesel and other fuels for various load conditions.
The programmable controller 12 allows for setting the vacuum pump 17 for a desired vacuum pressure. Existing diesel engines 36 do not operate with an internal vacuum or positive pressure in the crankcase. By drawing a vacuum through the PCV valve 18, using the vacuum pump 17, the inventive system 10 effectively creates a back pressure in the crankcase 34 and makes it possible to recirculate the blow-by gases. The controller 12 may also draw information from an exhaust sensor 32 to measure other qualities of exhaust gases produced by the diesel engine. Based on those exhaust sensor readings, the controller 12 may increase or decrease the vacuum pressure exerted by the vacuum pump 17.
The inventive system 10 adds an external vacuum pump 17, but it works as an internal pump in the engine 36 due to the configuration of the system 10. Because the controller 12 is fully programmable, the system 10 is operable and reacts in real-time, based on a real time GUI (not shown), and it can make operational decisions without user input.
In operation, when the vacuum pump 17 is pulling a vacuum, the blow-by gases are drawn from the crankcase 34 through the vent 72 and travel through the vent line 74, the PCV valve 18, and finally through the return line 76 and into the intake manifold 38 coupled thereto. The amount and duration of vacuum pulled by the pump 17 and the resultant quantity of blow-by gases drawn from the crankcase 34 to the intake manifold 38 via the PCV valve 18 is digitally regulated by the controller 12 shown in FIG. 1 .
The connection and operation of the PCV valve 18 by the controller 12 is as shown and described in U.S. Pat. No. 8,360,038, the contents of which are incorporated herein by reference. The connection and operation of the vacuum pump 17 by the controller 12 following similar designs and operational characteristics. Similar to the engine vacuum in gasoline engines, the vacuum pressure drawn on the diesel engine 36 by the pump 17 causes blow-by gases to be drawn from the crankcase 34, through the inlet and outlet on the PCV valve 18, and into the intake manifold 38.
The operational characteristics and production of blow-by gases is unique for each engine and each automobile in which an engine may be installed. The pollution control system 10 is capable of being installed in the factory or post production to maximize fuel efficiency, reduce harmful exhaust emissions, recycle oil and other gas and eliminate contaminants within the crankcase. The purpose of the pollution control system 10 is to strategically vent the blow-by gases from the crankcase 34 into the intake manifold 38 based on observed and measured blow-by gas production. Accordingly, the controller 12 digitally regulates and controls the PCV valve 18 based on engine speed and other operating characteristics and real-time measurements taken by the sensors 20-32.
Importantly, the pollution control system 10 is adaptable to any diesel engines in vehicles, as well as immobile engines used to produce energy or used for industrial purposes. Venting blow-by gases based on engine speed and other operating characteristics decreases the quantity of hydrocarbons, carbon monoxide, nitrogen oxide and carbon dioxide emissions. The pollution control system 10 recycles these gases by burning them in the combustion cycle. No longer are large quantities of the contaminants expelled from the engine via the exhaust.
In addition, the system 10 and controller 12 can be programmed with a timing delay on a cold start so as to close the PCV valve 18 or deactivate the pump 17 to eliminate the recycle of blow-by gases upon a cold start. This timing delay minimizes the recycling of blow-by when the engine is cold to make sure that the air entering the intake manifold 38 is clean as during emissions tests. When performing cold start emissions tests, emissions are very high on any internal combustion engine, including diesel. Thus, the controller 12 implements a timing delay sequence to allow the engine 36 to warm up before activating the vacuum pump 17 and PCV valve 18. So that the system 10 has full control of the output of the pump 17 and PCV valve 18, the controller 12 is fully programmable.
The system 10 can also be programmed with different variances depending upon the different emissions gases whether carbon dioxide, carbon monoxide, nitrous oxide, hydrocarbon, sulfur dioxide, or particulate matters. Whether the engine 36 is designed for low, ultra-low or super ultra-low emission standards, the system 10 can extend the life of the engine 36.
Hence, the pollution control system 10 is capable of reducing air pollution by forty to fifty percent for each engine, increasing fuel efficiency by as much as twenty to thirty percent, increasing horsepower performance by as much as twenty to thirty percent, reducing engine wear by as much as thirty to fifty percent (due to low carbon retention therein), and reducing the frequency of oil changes as much a ten-fold. Considering that the United States consumes approximately 870 million gallons of petroleum a day, a fifteen percent reduction through the recycling of blow-by gases with the pollution control system 10 translates into a savings of approximately 130 million gallons of petroleum a day in the United States alone. Worldwide, nearly 3.3 billion gallons of petroleum are consumed per day, which would result in approximately 500 billion gallons of petroleum saved every day.
The controller 12 can be pre-programmed, programmed after installation or otherwise updated or flashed to meet specific automobile or on-board diagnostics (OBD) specifications. In one embodiment, the controller 12 is equipped with self-learning software such that the vacuum pump 17 and PCV valve 18 are adapted to the optimal opening and closing timing of a particular engine 36. The controller 12 preferably mounts to the interior of the hood 14 of the automobile 16, as shown in FIG. 1 . The controller 12 may be packaged with an installation kit to enable a user to attach the controller 12 as shown.
Electrically, the controller 12 is powered by any suitable twelve volt circuit breaker. A kit having the controller 12 may include an adapter wherein one twelve volt circuit breaker may be removed from the circuit panel and replaced with an adapter (not shown) having multiple connections, one for the original circuit and at least a second for connection to the controller 12. The controller 12 includes a set of electrical wires (not shown) that connect one-way to the connector wires of both the vacuum pump 17 and the PCV valve 18 so a user installing the pollution control system 10 cannot cross the wires. The controller 12 may also be accessed wirelessly via a remote control or hand-held unit to access or download real-time calculations and measurements, stored data or other information read, stored or calculated by the controller 12.
In another aspect of the pollution control system 10, the controller 12 may modulate control of the vacuum pump 17 and PCV valve 18. The primary functionality of the vacuum pump 17 and PCV valve 18 is to control the amount of engine vacuum between the crankcase 34 and the intake manifold 38. The vacuum pulled by the pump 17 and the open/closed state of the PCV valve 18 solely dictates the air flow rate of blow-by gases traveling from the crankcase 34 to the intake manifold 38. In some systems, the vacuum pump 17 and PCV valve 18 may regulate air flow to ensure the relative pressure between the crankcase 34 and the intake manifold 38 does not exceed parameters according to the original equipment manufacturer (OEM). In the event that the controller 12 fails, the pollution control system 10 defaults back to OEM settings wherein the vacuum pump 17 and PCV valve 18 do not function because of the lack of pressure differential between the crankcase 34 and intake manifold 38 in a diesel engine.
The pollution control system 10 controller 12 may regulate the vacuum pump 17 and the PCV valve 18 based on engine operating frequency. For instance, the controller 12 may activate or deactivate the pump 17 and valve 18 as the engine passes through a resonant frequency. In a preferred embodiment, the controller 12 blocks all air flow from the crankcase 34 to the intake manifold 38 until after the engine passes through the resonant frequency. The controller 12 can also be programmed to regulate the pump 17 and PCV valve 18 based on sensed frequencies of the engine at various operating conditions.
A particularly preferred aspect of the pollution control system 10 is the compatibility with current and future OBD standards through inclusion of a flash-updatable controller 12. Moreover, operation of the pollution control system 10 does not affect the operational conditions of current OBD and OBD-II systems. The controller 12 may be accessed and queried according to standard OBD protocols and flash-updates may modify the bios so the controller 12 remains compatible with future OBD standards. Preferably, the controller 12 operates the vacuum pump 17 and PCV valve 18 to regulate the engine vacuum between the crankcase 34 and the intake manifold 38, thereby governing the air flow rate therebetween to optimally vent blow-by gas within the system 10.
In another aspect of the pollution control system 10, the controller 12 may modulate activation and/or deactivation of the operational components, as described in detail above, with respect to, e.g., the vacuum pump 17 and the PCV valve 18. Such modulation is accomplished through, for example, the aforementioned switches, on-delay timer or other electronic circuitry that digitally activates, deactivates or selectively intermediately positions the aforementioned control components. For example, the controller 12 may selectively activate the vacuum pump 17 and the PCV valve 18 for a period of one to two minutes and then selectively deactivate the same for ten minutes. These activation/deactivation sequences may be set according to predetermined or learned sequences based on driving style, for example. Pre-programmed timing sequences may be changed through flash-updates of the controller 12.
FIG. 3 illustrates an alternate embodiment to the system 10 shown in FIG. 2 that adds an exhaust diverter 58 to the exhaust outlet 64 of the engine 36. The exhaust diverter 58 is designed to selectively divert at least a portion of the exhaust gases from the engine 36 in response to signals from the controller 12. The diverted exhaust gases pass through recycle line 59 and are introduced into the intake manifold 38 where they are combined with the air coming from airline 42. An exhaust sensor/analyzer 32 can determine the content of the exhaust gases, with the controller 12 programmed to divert exhaust gases to the intake manifold 38 upon predetermined exhaust gas compositions.
The diversion of exhaust gases through the recycle line 59 combined with the airline 42 and the blow-by gases from the recycle line 76, the exhaust emissions will be diluted and re-combusted. The overall emissions composition profile will be reduced. Uncombusted emissions gases will be re-combusted. Remaining emissions gases will be diluted when mixed with air. This will produce much cleaner emissions. The system 10 will dramatically lower emissions by as much as 90% due to both re-combustion and dilution, resulting in a very clean diesel engine compared diesel engines without the inventive system 10.
FIG. 4 illustrates an alternative embodiment of the pollution control system 10 disclosed herein wherein evaporated oil in the blow-by gases exiting the crankcase 34 is condensed back into a liquid state and returned back into the crankcase 34 for reuse. The condensed oil may also be filtered by an oil filter to remove any contaminants therein prior to placement back into the crankcase 34. An oil trap 138 is disposed between the crankcase 34 and the PCV valve 18. As described above in detail, blow-by gases vent from the crankcase 34 via the vent line 74. In this embodiment, these blow-by gases enter the oil trap 138 before entering the PCV valve 18. The vacuum pump 17 and PCV valve 18 still regulate the quantity of blow-by gases that vent from the crankcase 34, in accordance with the embodiments described above.
The oil trap 138 may generally comprise a base 140 attached to an inverted frusto-conically shaped condenser 142. Blow-by gases enter the oil trap 138 at the approximate operating temperature of the engine 36. The blow-by gases travel to the oil trap 138 through an otherwise substantially constant volume of piping that comprises the vent line 74. Hence, the pressure in the vent line 74 between the vent 72 and the base 140 is relatively constant. Blow-by gases entering the oil trap 138 experience a rapid drop in pressure due to the shape and/or size of the oil trap 138. That is, the blow-by gases quickly enter into and fill the interior of the base 140 and, more importantly, fill the volume of the condenser 142. The same quantity of blow-by gases exiting the vent line 74 experience a sudden increase in volume due to the enlarged size of the base 140 and the condenser 142 relative to the size of the vent line 74. In turn, this causes a simultaneous drop in pressure, especially in the condenser 142. The drop in pressure allows particulates of oil to condense out from a gaseous state and back into a liquid state. Blow-by gases that remain in a gaseous state exit the condenser 142 through an auxiliary vent line 144 into the PCV valve 18 through the intake orifice 84.
The inverted frusto-conical shape of the condenser 142 funnels condensed liquid oil back into the base 140 of the oil trap 138. The sloped orientation of the vent line 74 allows the condensed liquid oil to drain back into the crankcase 34 for continued operation and lubrication of the engine 36. In this particular embodiment, the oil trap 138 enables the pollution control system 10 to capture and recycle oil back into the crankcase 34. This prevents some of the gaseous oil traveling with the blow-by gases from traveling back to the intake manifold 38 to be otherwise burned with the blow-by gases. This is particularly desirable as condensing and recycling oil back into the crankcase 34 extends the operational duration of the oil 70 therein, thereby prolonging the duration between needed oil changes. This is obviously beneficial as users decrease the quantity of oil consumed during operation of the engine 36, which corresponds to increased operational savings by changing the oil 70 less often.
With reference to FIG. 4 , a drain line 146 may be coupled to the oil trap 138 for returning the liquid oil to the crankcase 34. The vent line 74 and the drain line 146 may be coupled to different portions of the oil trap 138 so that the vacuum drawing the blow-by gas through the oil trap 138 does not interfere with the drainage of the liquid oil back to the crankcase 34. The condensed and trapped oil may pass through the drain line 146 to the crankcase via a dip stick chamber 148 of a dip stick 150, as illustrated.
With reference now to FIGS. 4 and 5 , blow-by gasses from the crankcase may pass through line 74 and into the oil trap 138 in such a manner so as to filter or separate the oil from the gasses. This may be by means of delivering the blow-by gasses into a top portion of the oil trap 138, as illustrated in FIG. 5 , whereby the blow-by gasses are passed through a filter or separator 154, such that oil droplets 154 are filtered or otherwise separated from the gasses. The oil droplets 154 are directed towards an outlet 156 of the oil trap 138 so as to be delivered back to the crankcase, such as the chamber 148 of the dip stick 150, or other chamber of the crankcase.
Filtering or separating the oil 154 from the gaseous blow-by gasses filters harmful contaminants from the oil before being returned to the crankcase. This extends the operational lifespan of the oil. Moreover, the blow-by gas diverted back into the intake manifold is purified from oil and contaminants, and thus will burn cleaner in the combustion chamber of the engine 36 and not create as many airborne contaminants.
The use of the pollution control system 10 in association with an automobile, as described above, is merely a preferred embodiment. The pollution control system 10 may be used with larger stationary engines or used with boats or other heavy machinery. Additionally, the pollution control system 10 may include one or more controllers 12 and one or more vacuum pumps 17 and/or PCV valves 18 in combination with a plurality of sensors measuring the performance of the engine or vehicle. Of course, the pollution control system 10 has application across a wide variety of disciplines that employ combustible materials having exhaust gas production that may be recycled and reused.
Although several embodiments have been described in detail for purposes of illustration, various modifications may be made to each without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims.

Claims

What is claimed is:

1. A pollution control system for a diesel engine, comprising:

a PCV valve having an inlet fluidly connected to a crankcase on the diesel engine and an outlet fluidly connected to an intake manifold on the diesel engine;

a vacuum pump associated with the PCV valve; and

a controller for selectively operating the vacuum pump to increase vacuum pressure on an intake manifold side of the PCV valve relative to a pressure on a crankcase side of the PCV valve based, in part, on measurements from an engine sensor.

2. The system of claim 1, wherein the vacuum pump lessens vacuum pressure on the intake manifold side during periods of decreased blow-by gas production to decrease the fluid flow rate through the PCV valve, and increases vacuum pressure on the intake manifold side during periods of increased blow-by gas production to increase the fluid flow rate through the PCV valve.

3. The system of claim 2, wherein the vacuum pump is fluidly disposed between the PCV valve and the intake manifold.

4. The system of claim 2, wherein controller operates the vacuum pump in real-time.

5. The system of claim 1, wherein the engine sensor comprises at least one of an engine temperature sensor, an accelerometer sensor, an exhaust sensor, a battery sensor, a PCV valve sensor, a cam position sensor, and/or an engine RPM sensor.

6. The system of claim 1, wherein the engine sensor comprises a cam position sensor to determine RPMs of the engine.

7. The system of claim 1, further comprising an oil trap fluidly coupled to the PCV valve for condensing vaporized oil in the blow-by gas into a liquid for reuse in the crankcase.

8. The system of claim 7, wherein a volume of the oil trap is relatively larger than a volume of a vent line carrying the blow-by gas to the oil trap from the crankcase.

9. The system of claim 8, including a drain line coupled to the oil trap for returning liquid oil to the crankcase.

10. The system of claim 9, wherein the vent line and the drain line couple to different portions of the oil trap such that the vacuum drawing the blow-by gas through the oil trap does not interfere with the drainage of the liquid oil back to the crankcase.

11. The system of claim 9, wherein the drain line couples to the crankcase via a dipstick chamber.

12. The system of claim 7, wherein the oil trap includes an internal oil filter.

13. The system of claim 1, further comprising an exhaust diverter fluidly connecting an exhaust outlet on the diesel engine to the intake manifold.

14. The system of claim 10, wherein the controller selectively operates the exhaust diverter to divert a portion of exhaust gases from the exhaust outlet to the intake manifold based, in part, on measurements from an exhaust analyzer.

15. A pollution control system for a diesel engine, comprising:

a vacuum pump fluidly disposed between the PCV valve and the intake manifold; and

a controller for selectively operating the vacuum pump to increase vacuum pressure on an intake manifold side of the PCV valve relative to a pressure on a crankcase side of the PCV valve based, in part, on measurements from an engine sensor comprising at least one of an engine temperature sensor, an accelerometer sensor, an exhaust sensor, a battery sensor, a PCV valve sensor, a cam position sensor, and/or an engine RPM sensor;

wherein the vacuum pump lessens vacuum pressure on the intake manifold side during periods of decreased blow-by gas production to decrease the fluid flow rate through the PCV valve, and increases vacuum pressure on the intake manifold side during periods of increased blow-by gas production to increase the fluid flow rate through the PCV valve.

16. The system of claim 15, wherein controller operates the vacuum pump in real-time.

17. The system of claim 15, wherein the engine sensor comprises a cam position sensor to determine RPMs of the engine.

18. The system of claim 15, further comprising an oil trap fluidly coupled to the PCV valve for condensing vaporized oil in the blow-by gas into a liquid for reuse in the crankcase, wherein a volume of the oil trap is relatively larger than a volume of a vent line carrying the blow-by gas to the oil trap from the crankcase.

19. The system of claim 18, including a drain line coupled to the oil trap for returning liquid oil to the crankcase.

20. The system of claim 19, wherein the vent line and the drain line couple to different portions of the oil trap such that the vacuum drawing the blow-by gas through the oil trap does not interfere with the drainage of the liquid oil back to the crankcase.

21. The system of claim 19, wherein the drain line couples to the crankcase via a dipstick chamber.

22. The system of claim 18, wherein the oil trap includes an internal oil filter.

23. The system of claim 1, further comprising an exhaust diverter fluidly connecting an exhaust outlet on the diesel engine to the intake manifold, wherein the controller selectively operates the exhaust diverter to divert a portion of exhaust gases from the exhaust outlet to the intake manifold based, in part, on measurements from an exhaust analyzer.