TURBULENT VENTURI CRANKCASE VACUUM GENERATOR

Description

COPYRIGHT NOTICE

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but reserves all copyright rights whatsoever. 37 CFR 1.71(d).

CROSS-REFERENCE TO RELATED APPLICATIONS

N/A

FIELD OF THE INVENTION

This invention relates generally to vehicle engines and specifically to devices for generating vacuum within an engine crankcase.

STATEMENT REGARDING FEDERALLY FUNDED RESEARCH

This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government.

BACKGROUND OF THE INVENTION

All engines generate “blow-by” or leakage past the piston rings, creating positive pressure in the crankcase. Blow-by consists of a combination of compressed air-and-fuel from the compression stroke and combustion of gasses leaking past the rings, along with associated by-products during the power stroke. Blow-by may include fuel, exhaust gasses, carbon and other contaminants that are introduced into the crankcase. Blow-by increases, crankcase pressure builds and robs power by increasing pumping losses, negatively impacting the ring seal. Blow-by introduces harmful contaminants into the crankcase lubrication system, impacting oil longevity and bearing life.

On performance engines, blow-by is typically exacerbated from increased compression ratios, supercharging, turbocharging, and or nitrous oxide use. These modifications done on motor to performance engines increase horsepower and torque. Enough positive pressure can build up in the crankcase during the piston's operation to adversely affect cylinder wall ring sealing. Positive crankcase pressure also robs horsepower and torque, increasing the likelihood of oil leaks.

Solving these problems is what modern cars manufactures accomplish when employing positive crankcase ventilation valves, known as a PVC valves. Automobile manufactures use several ways to effectively minimize crankcase pressure. Modern crankcase evacuation systems increase the effectiveness and draw air from inside the crankcase in an effort to create a negative pressure during engine operation. With lower than atmospheric pressure within the crankcase it has been proven to improve ring seal and reduce parasitic pumping losses.

The original Pan-Evac systems, connected the valve covers to the header collectors by way of a hose. At high engine-speed, exhaust gases rush past the vent tube protruding into the header collector, inducing vacuum (suction) in the crankcase. This setup was done in an effort to reduce crankcase pressure. Moroso introduced a heavy-duty vacuum pump (PN 22641) specifically engineered for crankcase evacuation duty.

External crankcase vacuum pumps provide significant power gains on both conventional and high-performance street engines, by promoting superior ring sealing and reducing pumping losses. Since the late 60s, the first passive crankcase evacuation methods or so-called Pan-Evac systems became popular among street racers. Today, manipulating the pan vacuum with a dedicated belt driven pump is the preferred method.

Pan-Evac system connects the valve covers to the exhaust header collectors with one-way check valves and vent tubes that penetrate into the exhaust stream at approximately 45 degrees. Exiting exhaust gasses pull a vacuum on the tubes, thus drawing excess crankcase pressure from the crankcase and discharging it out the exhaust. This action relieves blow-by, generating negative pressure in the crankcase, thereby reducing pumping losses and promoting improved piston ring seal. Although purely passive, one drawback of the system is it requires little, if no back pressure to function properly. Manufactures do not recommend evacuation tubes on engines with full exhaust systems. The reason for this is due to the fact that exhaust stream is made up of two main components.

When exhaust valves open, an energy wave exhibiting supersonic characteristics travels down the exhaust system. Exhaust gases also enter and also travel down the exhaust system. With the shock wave traveling faster than the exhaust gases, the shockwave encounters obstructions inside the interior of the exhaust system and reflects back upstream. This can have impacts on the flow of the exhaust gases. Thus there is:

• • a. Steady State Flow:

Exhaust Flow that that has an average velocity in the range typically between 100 to 150 linear feet per minute (based on engine size and operating rpm).

• • b. High Velocity Shock Pulses:

Shock pulses passing down exhaust tube typically exceed 500 linear feet per minute under the same operational conditions as the steady state flow. These pulses travel down the exhaust pipe temporarily increasing the local velocity as the shock wave exits the exhaust system.

The issue with legacy vent tube, Pan-Evac designs, is the negative impact from an equal and opposite pulses traversing back upstream in the opposing direction of the steady state flow. These high velocity reverse pulses are generated when a change in pipe diameter or direction in flow occurs. These pulses cause the flow of the exhaust to temporary reverse direction at the shock wave front. When these wave fronts collide with the vent tube it changes the flow, thereby pressurizing the crankcase.

The use of external vacuum pumps to evacuate excessive crankcase pressure, can result in less-than-atmospheric pressure conditions to occur within the crankcase. The size and rotational speed of the evacuation pump, determines the amount of vacuum generated within the crankcase. The amount of vacuum required to neutralize crankcase pressure, with optimal effect on pumping losses, and improving ring seal, is largely dependent on crankcase volume and that of the blow-by gasses slipping past the piston rings. The amount of vacuum needed to reduce pumping losses, is typically between 8 and 15 inches of Hg. Caution is suggested when exceeding 30 inches of Hg, as the amount of oil pressure drop impacts the wrist pins, bearings, and cylinder walls, and increases the probability of engine failure.

While the rotating assembly is primarily credited with generating windage in the crankcase, the pressure in the crankcase negatively impacts the piston velocity, slowing pistons, and exacerbating windage and parasitic pumping losses.

In general, external vacuum pumps are documented to produce power gains ranging from 10 to 40 horsepower.

Within the range of 8 to 15 inches of mercury, engines can benefit with lower tension rings to reduce friction, without fear of losing effective ring seal. Ring land tolerances and even stroke length and engine speed, affect the frequency and dynamics of piston reversal and its effect on ring performance. The benefit of crankcase pressure evacuation is particularly effective on larger displacement engines or those with power adders that generate higher cylinder pressure and consequently more blow-by.

Best performance occurs when optimum vacuum is achieved early in the engine rpm and maintained across the effective power band of the engine. The correct pump is sized and operated at the desired speed to generate the desired vacuum and flow capacity. Flow capacity in combination with a vacuum control valve maintains the desired amount of vacuum. If the pump begins to exceed the desired vacuum level, the control valve provides an adjustable air leak to prevent it. Adjustability is an important factor as it follows engine speed to ensure vacuum is maintained at ideal levels.

The problem with using an external belt driven pump on a street motor, is the extended usage wears out the bearings.

Another problem with external belt driven vacuum pumps, is the required area, needed to secure the pump to the motor may not be readily available, especially in modern vehicles. With space at a premium in modern vehicles it is often difficult to mount a proper sized vacuum pump. In addition to the mounting issues, the belt driven vacuum pumps have an associated parasitic loss in horsepower and torque caused by the drag of the belt driven pulley system.

On the other hand, the Pan evacuation systems with the vent tube penetrating the exhaust stream at 45 degrees generates insufficient vacuum to produce a significant increase in horsepower and torque in combination with a full exhaust system. A Moroso vent tube entering an engine exhaust flow at 45 degrees is the closest known prior art at the time of filing, and yet it has no characteristics designed for choked or turbulent flow. In addition, the 45 degree vent tube is limited to engines without complete exhaust systems. narrowing or a throat is not something that common sense would indicate would be useful.

Similarly mixing exhaust flows moving at different speeds does not seem to be particularly relevant to exhaust flow speed and thus to UPSTREAM pressure in the crankcase.

However, the present invention teaches that one particular device placed in the exhaust flow can be extremely beneficial, and can produce vacuum upstream, in the crankcase, and is not limited to this device only.

It would be preferable to provide a low weight, low cost, small size device to reliably further reduce pressure in the vehicle crankcase.

It would further be preferable if such a device had essentially no moving parts, but is not limited to this.

It would yet further be preferable to provide a new invention which can be used in space which is already used by the exhaust system, thus taking up no additional space, but is not limited to this.

It would yet further be preferable to provide such a device which can be used with known types of systems such as the external air-oil separator, or one way valves or the like, but is not limited to this.

It would additionally be preferable to provide a device which can reduce blow-by, reduce crankcase pressure, and despite that, also allow the use of lower tension rings to reduce friction at the same time, but is not so limited. It would further be preferable to provide a device which can increase horsepower and increase torque by means of these results.

It would further be preferable to provide a device which can increase positive pressure, and yet also increase the rate of positive pressure onset, so that a large turbo can provide useful positive pressure at lower engine speeds.

SUMMARY OF THE INVENTION

General Summary

As stated, the solution to all the above problems is the turbulent flow/hypersonic venturi crankcase vacuum generator. The crankcase vacuum generator is a multi stage venturi that generates sufficient vacuum at low engine speeds required to improve ring seal and reduce parasitic pumping losses in the crankcase, but is not limited only to that, other parts may be used if desired, and it may be used in combination with other systems. The turbulent venturi vacuum pressure reduction varies as engine speed is increased, providing a pressure reduction with great reliability.

The venturi is placed inside the exhaust stream (for example in the exhaust down pipe) and may be connected to a air oil separator within the crankcase, with a one way valve in between, but is not so limited. The air oil separator is not limited to any one configuration, but usually contains multiple ports, one of which contains an adjustable vacuum relief valve that is employed to regulate the internal vacuum within the air oil separator.

The air oil separator is then plumbed into the valve cover to allow for the crankcase to be evacuated.

This reliably provides increased vacuum in the crankcase of the motor vehicle, increasing power and torque. Turbo lag is noticeably reduced, increasing the onset of positive intake pressure at reduced engine RPM, another advantage of the device.

The device may have internal configurations designed to cause turbulent flow, supersonic flow, or even hypersonic flow.

Summary in Reference to Claims

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, for use with a crankcase having at least one crankcase vacuum line and an engine having at least one exhaust line, wherein the improvement comprises:

• • a venturi having the exhaust line as a first inlet and the vacuum line as a second inlet, and having the exhaust line as an outlet, the venturi having a throat disposed in fluid communication with the first inlet and the second inlet, and having a diffuser disposed in fluid communication with the throat and the outlet, the venturi dimensioned and configured to generate a flow of exhaust gases through itself, the venturi throat dimensioned and configured to generate a negative pressure in the second inlet;
  • whereby the venturi generates reduced pressure in the vacuum line;
  • whereby the vacuum line generates reduced pressure in the crankcase.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a crankcase vacuum generator, for use with a vehicle engine having an exhaust line for engine exhaust gases and a crankcase, the crankcase having a vacuum line, the crankcase vacuum generator comprising:

• • a venturi having an exhaust gases inlet nozzle allowing the exhaust gases to function as a motive fluid, a vacuum line inlet nozzle, a diffuser throat and a diffuser outlet nozzle;
  • an operative connection of the vacuum line to the vacuum line inlet nozzle of the venturi;
  • an operative connection of the exhaust line to the exhaust gases inlet nozzle of the venturi;
  • an operative connection of the diffuser outlet nozzle to the exhaust line;
  • the diffuser throat dimensioned and configured to generate flow of the exhaust gases therethrough;
  • whereby the venturi generates reduced pressure in the vacuum line;
  • whereby the vacuum line generates reduced pressure in the crankcase.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a crankcase vacuum generator, further comprising:

• • an exterior surface, the exterior surface having an alignment and securing device, the alignment and securing device dimensioned and configured to mechanically engage to a part of the vehicle engine;
  • whereby the venturi is maintained coaxial with the flow of exhaust gases.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a crankcase vacuum generator, further comprising:

• • an interior surface, the interior surface providing a passageway through the vacuum generator, and thus an operative connection of the exhaust gases inlet nozzle, vacuum line inlet nozzle, diffuser throat and the diffuser outlet nozzle.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, further comprising:

• • an internal geometry dimensioned and configured to accelerate exhaust gases passing through the vacuum generator to a first velocity.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the first velocity is greater than a speed of sound.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the vacuum generator is secured within such exhaust line.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the vacuum generator passageway functions as a section of such exhaust line.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface is dimensioned and configured to produce a turbulent flow of exhaust gases, whereby the venturi generates further reduced pressure within the vacuum line.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow further comprises:

• • a helical coil disposed within the passageway on the interior surface.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow further comprises:

• • helical ridges protruding from the interior surface.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow further comprises:

• • at least one constriction of the passageway protruding from the interior surface.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow further comprises:

• • the converging inlet gradually narrowing as it approaches the diffuser throat and the diffuser outlet gradually widening as it leaves the diffuser throat.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow further comprises:

• • dual counter-rotating rifling of the interior surface.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow further comprises:

• • a plurality of pins protruding from the interior surface into the passageway.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow generates vacuum regardless of a direction of flow through venturi.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow generates vacuum regardless of backpressure within the exhaust line.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide an improved crankcase vacuum generator, wherein the interior surface dimension and configuration producing the turbulent flow generates vacuum in an exhaust line in which pulsed pressure waves are present.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a crankcase vacuum generator, further comprising:

• • a body having first, second and third parts, the first, second and third parts being hollow;
  • the first body part having the exhaust gases inlet nozzle and the operative connection to the exhaust line, and further having a first threading;
  • the second body having a first open end having a second threading, the second threading dimensioned and configured to mechanically engage to the first threading, whereby when the first and second threadings are screwed together the exhaust gases inlet nozzle of the first part is disposed within the second body part;
  • the third body part having the diffuser throat and the diffuser outlet nozzle and the operative connection to the exhaust line, and further having a third threading;
  • the second body part further having a second open end having a fourth threading, the fourth threading dimensioned and configured to mechanically engage to the third threading, whereby when the third and fourth threadings are screwed together the diffuser throat of the third body part is disposed within the second body part.

It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a crankcase vacuum generator wherein the body comprises:

• • a high temperature alloy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional partially elevational view of a venturi according to the invention.

FIG. 2 is a cross-sectional view of a venturi according to the invention.

FIG. 3 is a cross-sectional view of a model of the venturi, showing hypersonic flow built up in the diffuser section.

FIG. 4 is a screen shot of a dynomometer test showing baseline results (control) versus results in the same vehicle and crankcase exhaust system with the invention installed.

FIG. 5a is a cross-sectional side view of a venturi of the invention mounted, showing structural details.

FIG. 5b is a cross-sectional side view of a venturi of the invention mounted and in use, showing sonic waves and exhaust flow both.

FIG. 6 is a cross-sectional assembled side view of the invention, which is comprised of three parts that are assembled together.

FIG. 7 is an exploded external side view of the invention showing the three parts disassembled.

FIG. 8 is an exploded cross-sectional side view of the invention showing all three parts unassembled.

FIGS. 9a and 9b are PRIOR ART figures of a study carried out on the flow characteristics of a cylinder operating at normal low RPM ranges, including a one dimensional model thereof.

FIG. 10 is a front elevational perspective view of a preferred embodiment and best mode presently contemplated for carrying out the invention.

FIG. 11 is a cross-sectional view of a turbulent flow venturi with tubular or coil shaped internal structure to increase turbulence.

FIG. 12 is a cross-sectional view of a turbulent flow venturi with raised internal structures to increase turbulence, along with a variable internal diameter.

FIG. 13 is a cross-sectional view of a turbulent flow venturi with dual counter-rotating rifling of the bore, combined with a gradual reduction in internal diameter.

FIG. 14 is a cross-sectional side view of the venturi with both raised tubular internal structures as well as pins.

FIG. 15 is a straight-through front view of the venturi with raised pins, showing an internal profile view of the invention.

FIG. 16 is a right front view of the invention in an embodiment having ears for fitting into place more securely.

FIG. 17 is a cross-sectional right front view of the invention in an embodiment having pins for reverse flows, ridges as well, and an annular constriction to the vacuum.

FIG. 18 is a cross-sectional right side view of the invention showing the pins for reverse flows and a better view of the annular constriction to the vacuum.

FIG. 19 is a cross-sectional right side view of the invention showing the rotating tube for reverse flows and the mounting mechanism for the rotating tube.

FIG. 20 is a cross-sectional right side view of the invention showing the rotating tube for reverse flows and the mounting mechanism, both rotated for flow in a first direction.

FIG. 21 is a cross-sectional right side closer view of the invention showing the rotating tube for reverse flows and mount, both rotated for flow in a first direction.

FIG. 22 is a cross-sectional right side view of the invention showing the rotating tube for reverse flows and mount, both rotated for flow in a second direction.

FIG. 23 is a cross-sectional right side closer view of the invention showing the rotating tube for reverse flows and mount, both rotated for flow in a second direction.

INDEX TO REFERENCE NUMERALS

FIG. 2

• • Turbulent vacuum generating device 200
  • Exhaust gases inlet nozzle 202
  • Vacuum line inlet nozzle 204
  • Venturi inlet nozzle 206
  • Diffuser throat 208
  • Diffuser nozzle 210
  • Connection to exhaust line 212
  • Connection to vacuum line (crankcase) 214
  • Connection to exhaust line 216

FIG. 3

• • Turbulent vacuum generating device 300
  • Diffuser throat 302
  • Turbulent flow 304
  • Diffuser nozzle 306
  • Inlet nozzle 308

FIG. 4

• • Dynomometer data report 400
  • Baseline (control) 402
  • Test (with venturi) 404

FIG. 5

• • Turbulent vacuum generating device 500
  • Vacuum line (to crankcase) 502
  • Alignment and securing devices 503
  • Exhaust line flow during capture by venturi 504
  • Bypass gas section (momentum aid) 506
  • Exhaust gas inlet nozzle 508
  • Constriction 510
  • Turbulent flow 512
  • Outlet nozzle (diffuser) 514
  • Exhaust line flow after venturi 516
  • Exhaust gas flow 518
  • Bypass gas 520
  • Positive pulse wave/sonic wave 522
  • Re-entrent gas 524

FIG. 6

• • Turbulent vacuum generating device 600
  • First body part 602
  • Second body part 604
  • Third body part 606
  • Inlet nozzle 608
  • Diffuser throat 610
  • Vacuum inlet 612
  • Attachment 614

FIG. 7

• • Turbulent vacuum generating device 700
  • First body part 702
  • Second body part 704
  • Third body part 706

FIG. 8

• • Turbulent vacuum generating device 800
  • First body part 802
  • Second body part 804
  • Third body part 806

(FIGS. 9a, 9b ARE PRIOR ART)

FIG. 10

• • Turbulent flow crankcase vacuum generator 1000
  • Vacuum inlet (from crankcase) 1002
  • Alignment and securing devices 1003
  • Exhaust gases inlet nozzle 1008
  • Exhaust gases outlet nozzle/diffuser 1014

FIG. 11

• • Constriction 1110
  • Helical coil 1126
  • Interior surface 1127

FIG. 12

• • Raised ridges 1228

FIG. 13

• • Dual counter-rotating rifling 1330

FIG. 14

• • Raised ridges 1428
  • Pins (indicated in both cross-section and oblique) 1432

FIG. 15

• • Interior surface 1527
  • Pins 1532
  • Interior passageway 1534

FIG. 16

• • Flush mount venturi 1600
  • Ears 1604
  • Raised ridges 1628

FIG. 17

• • Flush mount venturi 1700
  • Raised ridges 1728
  • Pins (for reverse flow) 1736
  • Annular constriction to vacuum 1738
  • Annular cavity inside constriction 1740

FIG. 18

• • Flush mount venturi 1800
  • Annular constriction to vacuum 1838
  • Annular cavity inside constriction 1840

FIG. 19

• • Movable tube 1942
  • Spherical/round rotating tube mount 1944

FIG. 20

• • Movable tube 2042
  • Spherical/round rotating tube mount 2044

FIG. 23

• • Movable tube 2342
  • Spherical/round rotating tube mount 2344

DETAILED DESCRIPTION

Glossary

This invention may include flow which is turbulent, supersonic flow and/or hypersonic, hypersonic generally means a multiple of the speed of sound, for example a speed greater than five times the speed of sound or greater than twice the speed of sound. This invention may include subsonic flow.

Exhaust gases refers to engine exhaust gases which are driven from an engine cylinder by action of the pistons, depending upon the thermodynamic cycle, 2 or 4 stroke engines, valve arrangements and so forth, and is not limited to one embodiment. Exhaust gases tend to flow in puffs or pulses, resulting in the problem mentioned previously with Moroso systems: the crankcase receives greater or lesser vacuum depending upon the pulses of exhaust gases. This problem is referred to herein as pulsed pressure waves, standing waves, sonic waves and so forth. Examples may be seen in FIGS. 5a and 5b.

Crankcase evacuation refers to the fact that gases and gas pressure underneath a piston head tend to cause a force upward on the piston, robbing a stroke of power. Evacuation of the gases underneath the piston produces greater power, torque, etc.

End Glossary

FIG. 1 is a cross-sectional partially elevational view of a venturi according to the invention.

In general principle, a venturi operates by having a pressurized (and thus accelerated) flow from a motive nozzle which enters are larger area containing gases from a vacuum line. In this drawing the vacuum line is entering from the bottom. The combined flow exits to the viewer's right, but is not limited this way.

Importantly, a low pressure zone is established in the vacuum line, but is not limited only there.

FIG. 2 is a cross-sectional view of a simple venturi according to the invention. This is a fairly simple venturi and is seen in FIGS. 6 through 8, though this is only the best mode presently contemplated and the invention is not limited to this embodiment only.

Vacuum generating device 200 has several prominent parts. Exhaust gases inlet nozzle 202 is the motive nozzle which drives the venturi. Venturi inlet nozzle 206 generally narrows as it approaches the diffuser throat 208.

This embodiment has a simple straight inlet nozzle, in contrast to the inlet nozzle seen in FIG. 1. This embodiment may produce subsonic, supersonic or hypersonic flow, as discussed below. In other embodiments, seen in FIGS. 10 through 15, the flow may produce the desired vacuum by means of turbulent flow.

As is well known, when compressible gases in motion are compressed, pressure goes up but speed of flow goes up as well. This is in fact a major principle of operation of wind tunnels. Using such constrictions, it is possible to produce even supersonic flow. It is also possible to produce hypersonic flow, while the pressures and flow rate conditions permit.

In the present invention, finite element analysis and computational fluid mechanics have been used to create a venturi which accelerates flows to supersonic at the diffuser throat 208 and then to create a subsonic, sonic or hypersonic wave front within the diffuser nozzle 210. (In later Figures, the embodiments feature turbulent flow.)

Vacuum line inlet nozzle 204 is in fact the exact reason for this effort to create the high speed flow. The great reduction in pressure created in the vacuum line inlet nozzle 204 will be carried upstream, in effect as an “increased reduction” of pressure which is transmitted to the crankcase interior, resulting in lower pressure under the pistons and increased power and torque, and notably, faster onset of turbo positive pressure. The invention is not limited to producing all of these results under all conditions.

Connection to exhaust line 212 connects the inlet nozzle 202 to the exhaust gases which drive the venturi 200, while the connection 214 to the vacuum line leads from the crankcase. Finally, connection 216 returns the combined gases back to the exhaust line on the downstream side of the device 200 but is not limited to this.

FIG. 3 is a cross-sectional view of a model of the venturi, showing high speed flow built up in the diffuser section.

High speed flow vacuum generating device model 300 has a simplified diffuser throat 302, narrowing to diffuser nozzle 306 and downstream of inlet nozzle 308. The invention is not limited to a simplified diffuser throat of course.

Modeling has shown that hypersonic flow 304 may be generated downstream of the throat 302, creating the suction upstream.

FIG. 4 is a screen shot of a real world engineering test, in this case a dynomometer test showing baseline results (control) versus results in the same vehicle and crankcase exhaust system with the invention installed. These test results are only one set of results showing the performance improvements, the invention is not limited to only these results or any other single set of results or type of results.

Dynomometer data report 400 shows the baseline test results for a given engine. This was a real world test conducted on a 2011 Mitsubishi Lancer Evolution GSR, performed on a Mustang Dynomometer at an elevation of approximately 4,000 feet (the dyno located at a confidential performance shop in Denver Colorado, thus the high elevation). The venturi was installed as explained herein to become the junction of the exhaust gases/crankcase gases evacuation lines, along with a 6AN hose with a one-way flapper to operate as a one-way valve, and furthermore with an air-oil separator catch can to prevent/reduce entrance of oil into the venturi.

Baseline (control run) 402 is seen to be noticeably lower than the test run 404 with the venturi installed. Importantly, there is a defined bump at around 2000 RPM (see lower left corner of graph) representing a turbo producing positive output pressure faster than it otherwise would, followed by a long ramp up during which the test (with venturi) 404 curve is always either equal to or exceeding the baseline 402 curve.

Thus the modeled results discussed previously are found to in fact be replicated on the dyno, in the real world, and are not limited to only these results, as previously stated.

Baseline horsepower of 543 was increased to 565 bhp. Baseline torque of 444 ft-lb was increased to 460 ft-lbs. Needless to say increases of 3-5% in these metrics are very desirable to high performance drivers and owners, especially when they can be achieved with a low cost, low weight device.

FIG. 5a is a cross-sectional side view of a venturi of the invention mounted, showing structural details. FIG. 5b is a cross-sectional side view of a venturi of the invention mounted and in use, showing sonic waves and exhaust flow both.

Vacuum generating device 500 may have either high speed flow characteristics or turbulent flow characteristics. In this embodiment, the device is largely straight through flow, (of one branch 504 of overall exhaust gas flow 518) however, a ram jet effect is achieved by the inlet nozzle 508 have a slight flange shape to it. In addition, this embodiment has a constriction 510 right at the vacuum line 502, which runs from the crankcase.

Alignment and securing devices 503 may of course be bolts, bands, clamps, pins, welds, and so forth. Exhaust line flow (during its capture by the venturi) 504 is in this embodiment only a fraction of the total flow. Notice that a bypass gas flow 506 serves as a momentum aid: this flow increases the speed of the flow entering the inlet 508. A similar bypass flow/bypass vent may be seen at 520. In other embodiments seen below, the entire flow or substantially the entire flow enters the venturi with only modest bypass, or no bypass at all. Re-entrent gas 524 is shown moving from the main flow into the flow from the diffuser 514, again this is helpful in maintaining flow momentum.

Constrictions 510 in this embodiment take the form of two shallow toroids in the interior passageway of the venturi.

Turbulent flow 512 begins after the constrictions and aids the gain of negative pressure (vacuum) within the vacuum line 502 from the crankcase.

Exhaust line flow 516 is located after the venturi and is still somewhat turbulent.

One important issue which has bedeviled development is the presence of standing waves/positive pulse waves/sonic waves 522 as will be discussed further in reference to FIG. 9. In the present invention, it has been important to develop dimensions and configurations which support vacuum induction regardless of the presence of such waves, back pressure, shock waves (such as generated in the hypersonic/supersonic embodiments), and even exhaust gases flowing BACKWARD under some circumstances. In general, mirror image configurations of the venturi have been proven useful in allowing the invention to function with gas flowing in the correct direction, backward, or pressure waves of various types.

Alignment features may be a rail or stud or bump, etc. It serves the purpose of allowing immediate accurate fit of the device to the exhaust & crankcase lines, by matching any useful feature already found on those lines or another part of the engine. Obviously the alignment feature is not limited to any one shape, form, structure, etc.

The testing of this embodiment was carried out at high altitude on a course ending at Colorado Springs airport, making runs both with and without the device installed in the exhaust system. Acceleration and deceleration were controlled to be the same across test runs. In the stock configuration, the 1999 Toyota Tacoma with 4 wheel drive and an automatic transmission achieved 16-18 miles per gallon. However, with the device installed, millage increased to 21-22 miles per gallon. A 17% increase in fuel economy is obviously quite significant, both for saving money and for aiding the environment.

The pressure gauge (mounted to the crank case for testing) indicated that the blow-by generated less than 0.5 PSI during the high load portion of the test. It was noticed (qualitative data) that acceleration from an idle was also greatly improved. The present design was deemed to be not yet optimized in terms of evacuating the crankcase entirely. Thus, further structures were added, seen in FIGS. 10 through 15.

FIG. 6 is a cross-sectional assembled side view of the invention, which is comprised of three parts that are assembled together. It is not limited to three but may be any number of parts from one up to any practical number of parts.

Turbulent vacuum generating device 600 has a first body part 602, a second body part 604 and a third body part 606. Threading visible in the drawing shows how they are attached together and all three have a generally cylindrical passage through, creating hollow interiors.

This method of construction offers some advantages, which is why it is one of the embodiments and modes presently contemplated for carrying out the invention. It is not the only embodiment, for example, see FIG. 5 for a related mode, and the invention is not limited to his embodiment.

Inlet nozzle 608 actually protrudes from first body part 602 inside of the second body part 604, meaning that it very slightly protrudes into diffuser throat 610. Diffuser throat 610 of course protrudes from the third body part up into the second body part. The two do not touch, leaving a gap for vacuum generation at the throat. This is not the only arrangement and the invention is not limited this way.

Vacuum inlet 612 enters from the side of the venturi. It is worth remembering that while the motive nozzle (inlet nozzle 608) has a large volume of gas flow, the vacuum inlet 612 from the crankcase has very little flow volume by comparison. The objective is to generate the steady vacuum which is transmitted from the venturi to the crankcase. The gap between the two nozzle parts allows this vacuum.

Attachment 614 allows connection to the engine, etc.

One significant feature discussed previously is that placing an obstruction, even a narrowing, into a flow of engine exhaust gases is inherently, obviously, intuitively, counter-productive, as it will build back pressure.

But inherent, obvious intuition is wrong. As the modeling (see FIGS. 1 and 2) and the testing (see FIG. 4) all showed, the turbulent venturi generates negative pressure, which is exactly what it was created to do, thus reducing or eliminating the negative effects of the constriction and providing an overall higher level of engine output power. The present invention is counter-intuitive but has been proven to work.

FIG. 7 is an exploded external side view of the invention showing the three parts disassembled.

Turbulent vacuum generating device 700. First body part 702 has the inlet nozzle projecting, as does the third body part 706. Second body part 704 accepts both and also hosts the vacuum line connection seen.

FIG. 8 is an exploded cross-sectional side view of the invention showing all three parts unassembled. The threading which may optionally connect the parts is more easily seen. In production models this threading is likely to be replaced.

Turbulent vacuum generating device 800, first body part 802, second body part 804 and third body part 806 are all seen clearly.

FIGS. 9a and 9b are PRIOR ART figures of a study carried out on the flow characteristics of a cylinder operating at normal low RPM ranges, including a one dimensional model thereof.

The PRIOR ART analysis determined that a standing wave developed within the exhaust system, can develop into a whole series of standing waves, and has variable amplitude and phase with the motions of the crank/pistons. This standing wave can be an issue in venturi design. Therefore it is necessary to develop venturi designs which defeat the standing wave problem either by being agnostic to the presence of such waves, or by harnessing the pressure waves for the benefit of the generation of vacuum.

FIG. 10 is a front elevational perspective view of a preferred embodiment and best mode presently contemplated for carrying out the invention.

Turbulent flow crankcase vacuum generator 1000 has the vacuum inlet (from the crankcase) 1002, the alignment and securing devices 1003, the exhaust gases inlet nozzle 1008, the exhaust gases outlet nozzle (diffuser) 1014.

This view does not show the various internal configurations of the internal surface and the passageway therethrough.

It will be understood that at low engine speeds, the addition of turbulence generators allows the achievement of highly turbulent flow, which in turn creates more vacuum even when the exhaust gas velocity is low.

FIG. 11 is a cross-sectional internal view of a turbulent flow venturi with tubular or coil shaped internal structure 1126 to increase turbulence. This is one configuration which does not necessarily require the interior surface 1127 itself to provide all of the turbulence generation: a helical coil 1126 could be secured to the internal surface1127 as shown. Other devices or structures may be secured to the interior surface in addition to this.

Constriction 1110 is much as seen previously.

This design performed well when tested on a sealed 2015 Toyota Tacoma V6 engine (thus with newer rings, etc). Crankcase vacuum reached 15 inches of mercury (negative 7.36 psi, ie pressure reduction of almost 50% of sea level ambient, under moderate loading. Under higher loads (moving up a long slope having a quite steep grade (20-30%) the drop was only 3 inches of mercury (less than 2 psi pressure reduction) and thus while the performance at moderate loading is quite good, the performance at higher loading and full throttle was not deemed adequate: in some cases vacuum was no longer even present.

FIG. 12 is a cross-sectional view of a turbulent flow venturi with raised internal structures to increase turbulence, along with a variable internal diameter. In this embodiment, raised ridges 1228 may be a helical pattern, or may make an entirely different shape.

FIG. 13 is a cross-sectional view of a turbulent flow venturi with dual counter-rotating rifling 1330 of the bore, combined with a gradual reduction in internal diameter. The rifling 1330 is of course shallow grooving to the bore. Notice that this embodiment also features a gentle gradual narrowing rather than a constriction or a straight bore.

Test results on this design showed that at low engine loading and low exhaust gas velocity the results were not satisfactory.

Thus, a combination approach is tried, in which structures are used together in order to achieve both high load and low load vacuum.

FIG. 14 is a cross-sectional side view of the venturi with both raised tubular internal structures 1428 as well as pins 1432. The raised ridges 1428 may be augmented with other turbulence generating structures, in this embodiment, pins 1432. The pins are shown in both cross-section and oblique, which may be confusing but this becomes clearer in reference to FIG. 15. FIG. 15 is a straight-through front view of the venturi with raised pins 1532, showing an internal profile view of the invention. As is clear the pins 1432 of FIG. 14 are at different radial locations around the bore and thus in FIG. 14 were shown in both cross-section and oblique view.

Interior surface 1527 may have, in addition to pins 1532, other structures as discussed.

Interior passageway 1534 can be most easily seen in this figure as it passes through the venturi from end to end. (For example, from 504 to 514 of FIG. 5b).

FIG. 16 is a right front view of the invention in an embodiment having ears for fitting into place more securely. The flush mount venturi 1600 features a somewhat squared off frontal view due to the form fitting ears 1604 which allow it to fit into place in the overall exhaust system and the overall engine with a more stable and secure fit.

Raised ridges 1628 are partially seen through the open end and as previously discussed serve to help provide the turbulent flows of the invention.

FIG. 17 is a cross-sectional right front view of the invention in an embodiment having pins for reverse flows, ridges as well, and an annular constriction to the vacuum. Flush mount venturi 1700 has the raised ridges 1728 such as previously discussed.

Pins 1736 are shown and it is important to note that these provide for turbulence during the times of reverse flow. These periods of reverse flow (discussed previously) would possibly result in laminar flow if not for the pins 1736: due to the pins, flow in both directions is turbulent.

Annular constriction 1738 is of course connected to vacuum (NPT) as previously discussed. However, this constriction is hollow, which results in an annular cavity 1740 inside constriction 1738. This may provide better access to the vacuum and better negative pressure onto the vacuum.

FIG. 18 is a cross-sectional right side view of the invention showing the pins for reverse flows and a better view of the annular constriction to the vacuum. Flush mount venturi 1800 and the annular constriction (connected to vacuum) 1838 have within them the hollow toroid/ring allowing better distribution of vacuum due to the ring shaped cavity 1840.

FIG. 19 is a cross-sectional right side view of the invention showing the rotating tube 1942 for reverse flows and the mounting mechanism 1944 for the rotating tube. Movable tube 1942 is physically constrained so that it may rotate, but only axially along the venturi device. It may be made of materials having a low coefficient of friction such as stainless steel and C-630 bronze, whereby the action of the gas flow within the device can move the tube from hanging directly downward to an angle pushed by the flow. (Note that the angle should be constrained, for example, to 45 degrees from the vertical). The mounting 1944 may be a spherical ball with the tube 1942 projecting downward therethrough, or it may be a disc or other device allowing the desired range of motion only: axially, within the angular limit desired.

FIG. 20 is a cross-sectional right side view of the invention showing the rotating tube 2042 for reverse flows and the mounting mechanism 2044, both rotated for flow in a first direction, while FIG. 21 is the same view of the invention but closer, showing the rotating tube 2042 for reverse flows and mount, 2044, both rotated for flow in a first direction.

FIG. 22 is a cross-sectional right side view of the invention showing the rotating tube for reverse flows and mount, both rotated for flow in a second direction. FIG. 23 is a cross-sectional right side closer view of the invention showing the rotating tube 2342 for reverse flows and mount 2344, both rotated for flow in a second direction.

By this means the pressure and flow may be controlled in a variable manner dependent upon the direction of flow.

This disclosure allows use of the invention, but does not limit the claims and scope of legal protection of the invention in any way.

The disclosure is provided to render practicable the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims.

Methods and components are described herein. However, methods and components similar or equivalent to those described herein can be also used to obtain variations of the present invention. The materials, articles, components, methods, and examples are illustrative only and not intended to be limiting.

Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventors intend these to be encompassed within this specification. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way. This disclosure is intended to be exemplary, and the claims are intended to cover any modification or alternative which might be predictable to a person having ordinary skill in the art.

Having illustrated and described the principles of the invention in exemplary embodiments, it should be apparent to those skilled in the art that the described examples are illustrative embodiments and can be modified in arrangement and detail without departing from such principles. Techniques from any of the examples can be incorporated into one or more of any of the other examples. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.