Pollution control system for internal combustion engines

Abstract

A pollution control system for internal combustion engines including a crankcase unit for scavenging the blowby gases from the oil pan and an exhaust unit for scavenging the exhaust gases in the engine and exhaust manifold.

Description

BACKGROUND OF THE INVENTION

The matter of pollution of the atmosphere arising from the operation of internal combustion engines has intensified with the regular annual increase of automotive vehicles on the highways. The problem has been attacked on all sides with many and diverse purported solutions. However, many of the proposed solutions turn out to have technical or economical drawbacks.

Accordingly, an object of this invention is to provide an improved system for materially reducing air pollution stemming from the operation of internal combustion engines.

Another object of this invention is to provide a system of the character described, which is efficient in operation, is economical to manufacture and install and which will extend the normal life of the engine with which it is associated.

A further object of this invention is to provide a system of the character described which comprises a crankcase scavenger and an exhaust scavenger, which cooperate to bring the hydrocarbon emission of blowby gases and unburned fuel into the air, to a safe level.

Yet another object of this invention is to provide in a system of the character described, scavenger units for the crankcase and exhaust which operate automatically in response to the operation of the engine.

Still another object of this invention is to provide in a system of the character described, a crank case scavenger unit which includes a series of compression chambers with calibrated venturi orifices through which the blowby gases pass to be compressed and atomized and admixed with air to increase their combustibility before the same are drawn back into the combustion chambers for further burning.

Still a further object of this invention is to provide in a system of the character described, an exhaust scavenger unit which is actuated by the engine's pressure and vacuum cycles; wherein the pressure of the exhaust gases operates a valve to prevent gases from escaping into the atmosphere, while during the vacuum cycle, air is drawn through a filter and provides a reservoir air supply for the engine cylinders on a demand basis.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view showing an internal combustion engine and associated crank case and exhaust scavenger units embodying the invention;

FIG. 2 is a side elevational view in section showing the crankcase scavenger unit;

FIG. 3 is a top plan view thereof;

FIGS. 4 to 11 are top plan views of the several venturi plates contained therein;

FIG. 12 is a sectional view taken on the line 12--12 of FIG. 7;

FIG. 13 is a side elevational view showing the exhaust scavenger unit;

FIG. 14 is an enlarged, partial side elevational view thereof in section;

FIG. 15 is a plan view showing an element of the filter casing portion thereof;

FIG. 16 is a plan view showing the bottom wall portion of the filter cage;

FIG. 17 is a plan view showing the top wall thereof;

FIG. 18 is a side elevational view in section showing the associated valve elements thereof; and

FIG. 19 is a perspective view showing the valve member and the lower seat therefor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1, E designates a conventional internal combustion engine having a crankcase scavenger unit generally indicated at 10 and an exhaust scavenger unit generally indicated at 11, associated therewith and embodying the instant invention.

The crankcase scavenger unit 10 is conveniently mounted in an upright position, on the firewall 12 of the engine compartment, rearwardly of engine E, by suitable strap means 13. Unit 10 is a chambered member having an upper outlet 14 and a lower inlet 15. Outlet 14 is connected by a hose 16 to a tapped opening in the intake manifold 17 at a point adjacent the carburetor C, indicated at 18, while inlet 15 is connected by a hose 19 to a tapped opening in the valve cover 20 at a point 21 remote from the oil filler neck FN. If the engine is provided with a PCV system (positive crankcase ventilation), the regulator valve thereof must be removed.

Thus, there is a direct movement of air through the oil filler cap, through the push rod openings and ventilating tubes to and through the oil pan from which the blowby gases that have collected in the oil pan are mixed with air drawn back through the opposite side of engine E ventilating tubes and push rod openings into the bottom of unit 10 by way of inlet 15. This is accomplished by the normal engine vacuum and in accordance with the pressure thereof.

The crankcase unit 10 comprises an upper tubular casing portion 22 having the outlet 14 extending from the upper end thereof, and a lower casing portion 23 having the inlet 15 extending from the lower end thereof. The casing portions 22, 23 are held togather by a locking ring 24 having an inwardly extending radial flange 25 for engaging an outwardly extending radial flange 26 on casing portion 23, together with a sealing O ring 27; the ring 24 and casing 22 having interengaging threaded portions.

Within the lower casing portion 23 is disposed a fibrous filter body 28, which is supported on a perforated disc 29 mounted in the lower end of the casing.

The interior of unit 10 is subdivided into compression and atomization chambers defined by a series of vertically stacked venturi plates 30 and 31A to 31G. Each of the plates is provided with one or more ports which are in vertically staggered relation to each other.

Thus, plate 30 is a circular disc having a central port 33. The remaining plates 31A to 31G have upstanding spacing rims 32, whereby plates 30 and 31A to 31G are maintained in determined, vertical spacing; the lowermost plate 31G being seated on flange 26 of lower casing portion 23.

Plates 31C and 31E also have central ports 33A and 33B respectively. Plates 31A and 31D have a plurality of circumferentially located ports 34, 34A respectively; while plates 31B, 31F and 31G have pairs of diametrically related ports 35, 35A and 35B respectively. It is to be noted that all ports in plates 30 and 31A to 31G are chamfered on opposite sides, as indicated in FIG. 12, at CH.

It is understood that the plates 30 and 31A to 31G are arranged within unit 10 to provide tortuous paths for the upwardly moving gases as they pass through the various ports which are in successively offset relation to each other.

In operation, the blowby gases and air admixed therewith moves upwardly through filter 28 where large particles of carbon are removed therefrom, as well as major portions of sludge and varnish, preventing the same from passing through the engine E.

The gases then continue upwardly through the ports of the plates where residual sludge or varnish is trapped and the gases impinge on baffle surfaces of the several plates to effect a breakdown of the hydrocarbons, further admixture of air therewith, together with vaporization and atomization as the gases are drawn through the venturi ports, with discharge into the successive chambers. The accompanying turbulence of the gases as they move in the tortuous paths, further aids in breakdown of the hydrocarbons, and atomization. Finally, the gases are homogeneously admixed with air at the time they reach outlet 14.

It is understood that the spacing between the plates and the sizes of the venturi ports are carefully calibrated to take advantage of the vacuum action through the chambers and to provide a desired resistance to the gases as they are compressed and atmozed at high velocity pressure values. Thus, when the blowby gases and air have reached a predetermined density or state of compression, resistance is overcome and they pass through the venturi port into the next chamber, where the action is repated.

A check valve 40 on a seat 41 in the upper end of casing 22 becomes effective in the event of any reverse pressure condition thereby preventing gases from passing back into the oil pan.

It has been found that scavenger unit 10 is effective to prevent solid contaminants of the blowby gases from being drawn back into the engine, homogenizes the gas mixture including additional air and realizes a high degree of atomization which allows the mixture to readily combine with the usual fuel-air mixture at the base of the carburetor C or at the top of the manifold.

The exhaust scavenger unit 11 is mounted on the exhaust manifold EM of engine E, by way of tapped openings 45, 46. The unit 11 comprises a valve housing 46A having an inwardly extending radial flange portion 47 intermediate the ends thereof and opposed openings 48 beneath said flange portion to receive the inner ends of tubings 49. Tubings 50 are telescopically related to tubings 49 and have a right angle arm portion 51. Threaded ferrules 52 mounted on the lower ends of tubing arms 51 are secured in place by nuts 53; the ferrules 52 being threaded into openings 45, 46 in manifold EM.

Lock nuts 54 fix the tubings 49, 50 in adjusted relation to each other, to suit the specific spacing of openings 45, 46 in the exhaust manifold EM.

Mounted on the upper end of housing 46A is a filter unit 55 comprising a casing 56 closed at its bottom end by a plate 57 having edge slots 58 to admit air into the interior thereof. Within casing 56 is a fibrous filter unit 59 retained in a cage including a tubular wall 60, a spider top wall 61 and an annular bottom wall 62, which seats on plate 57.

A frustoconical valve member 63 is arranged for limited movements between an upper valve seat 64 and a lower valve seat 65. The upper valve seat 64 comprises a tubular member 66 having a conical seat portion 67 at the lower end thereof and a tubular portion 68 of reduced diameter at the upper end thereof. The valve seat 64 is fixed in housing 46A with the tubular portion 68 projecting upwardly through the opening in plate 57 and the bottom wall 62 of the filter cage and into the lower end of a central recess 69 in filter unit 59

The lower seat 65 comprises a base portion 70 seated on flange portion 47 of housing 46A and frustoconical portion 71 upstanding from base portion 70 which is formed with radial slots 72.

In operation, the unit 11 is controlled by the pressure and vacuum cycles of the engine E alternating at very high speeds. Thus, the pressure of the exhaust gases forces valve member 63 into sealing relation to the upper valve seat 64, to prevent any exhaust gases from escaping to the atmosphere. With the vacuum cycle, valve member 63 is drawn against the lower valve seat 65, allowing air to be drawn through filter 59 and into distributor tubes 49 and thence into each cylinder of the engine as demand occurs.

Further, the unit 11 automatically supplies air to the cylinders of the engine to scavenge the exhaust gases left from the preceding stroke, mixing such gases with the air and thus improving the mixture supplied to the cylinders on the next stroke.

Claims

I claim:

1. In an antipollution system for internal combustion engines, scavenger means for the crankcase of said engine, said crankcase scavenger means comprising a housing having inlet means and outlet means at the opposite ends thereof, conduit means connecting the inlet means to the valve cover of the engine, conduit means connecting the outlet means to the intake manifold of said engine, spacer means within said housing for forming a plurality of successive aligned chambers, each spacer means being formed with at least one venturi opening whereby blowby gases in the crankcase are passed through said successive chambers for breakdown of the hydrocarbons thereof, atomization and admixture with air.

2. A system as in claim 1, wherein said spacer means comprises a plurality of plates, each plate being formed with at least one venturi openings, the openings in adjacent plates being in offset relation to each other.

3. A system as in claim 2 wherein filter means is disposed within said housing between the inlet means thereof and the spacer means at one end thereof.

4. A system as in claim 2, wherein each venturi opening in said plates is defined by chamfered bevel edge portions on opposite sides of said plates.