US3034290A

US3034290A - Exhaust treatment device with air compressor regulator

Info

Publication number: US3034290A
Application number: US71473A
Authority: US
Inventors: Gary Wright Wesley
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-11-25
Filing date: 1960-11-25
Publication date: 1962-05-15
Anticipated expiration: 1979-05-15

Description

W. W. GARY May 15, 1962 EXHAUST TREATMENT DEVICE WITH AIR COMPRESSOR REGULATOR Filed Nov. 25, 1960 3 Sheets-Sheet 1 INVENTQR. VVQ/GHT W: 6/727 M A TrQEA/Em.

May 15, 1962 w. w. GARY 3,034,290

EXHAUST TREATMENT DEVICE WITH AIR COMPRESSOR REGULATOR Filed Nov. 25, 1960 3 Sheets-Sheet 2 INVENTOR.

BY /me/ 147- TOE/VEYS.

May 15, 1962 w. w. GARY 3,

EXHAUST TREATMENT DEVICE WITH AIR COMPRESSOR REGULATOR Filed Nov. 25, 1960 3 Sheets-Sheet 5 VENTOR u lem" 642 M m, 5 E

3,034,290 EEIAUST TREA'IWNT DEVICE Wl'l'ii AIR COMPRESSOR REGULATOR Wright Wesley Gary, 2317 Kimbridge Road, Beverly Hills, Calif. Filed Nov. 25, 1960, Ser. No. 71,473 12 Claims. (Cl. 60-30) The present invention relates to air compressors or pumps, and it relates particularly to a novel compressorregulator combination adapted to furnish fresh air to the exhaust system of an internal combustion engine to promote oxidation of unburned hydrocarbon and carbon monoxide exhaust components in anti-smog apparatus associated with the exhaust system.

Exhaust gases from internal combustion engines, and particularly from automobile engines, contain some unburned hydrocarbons which accumulate in the atmosphere and react to sunlight to form smog which causes eye irritation, is harmful to agricultural production, and appears to be a substantial human health hazard. Such exhaust gases also include carbon monoxide which, although not appearing to be a smog producing agent, is a poisonous gas and as such constitutes a considerable health hazard. A great deal of effort has been expended in recent years in the development of anti-smog apparatus. One form of such apparatus is the afterburner for direct burning of the undesired materials at temperatures above 2000" F. Another form is the catalytic converter for catalytically oxidizing or burning the. unwanted materials at temperatures above about 500 F. In my copending ap plication Serial No. 27,721, filed May 9, 1960 for Catalytic Converter System for Internal Combustion Engines 1 have illustrated, described and claimed apparatus for oxidizing the unburned hydrocarbon and carbon monoxide components of the engine exhaust by a novel combination of direct ignition burning and catalytic oxidation, which I have found to provide much more efficient oxdation of these unwanted exhaust components over the entire range of engine operating conditions than either an afterburner or a catalytic converter used alone.

Regardless of the type of apparatus employed for oxidizing the hydrocarbon and carbon monoxide components of the engine exhaust, whether it be an afterburner, a catalytic converter or apparatus such as'that described in my said copending application Serial No. 27,- 721 involving both direct ignition burning and catalytic oxidation, it is necessary to introduce fresh air into the exhaust line upstreamof the oxidizing apparatus in order to support the combustion or oxidation of the unwanted exhaust components. I have found in practice that the most practical source of supply of fresh air for the exhaust system is an air compressor or pump of the positive displacement type which is driven by the engine fan belt. However, the air requirements for efficient oxidation of the unburned hydrocarbons and carbon monoxide in the exhaust system at relatively high speeds, as in freeway driving, are only slightly greater than the requirements at engine idle speeds so that the air compressor must include means for controlling the compressor output rate to a relatively small increase upon relatively large increases in engine speed.

The following example illustrates some of the factors which must be considered in connection with the air supply source. This example is based upon the use of a 235 cubic inch displacement engine, such as a Chevrolet 6 cylinder engine, it being understood that more air would be required for larger displacement engines. In the example, my catalytic converter system set forth in my said copending application Serial No. 27,721 is employed for oxidizing the unburned hydrocarbons and carbon monox ide by combined direct ignition burning and catalytic oxidation.

In tests made with such equipment, at engine idle speeds of about 450 r.p.m., my catalytic converter system has been found to require from about 1 /2 to 2 cubic feet of air per minute. At this time the amount of excess air which is added to the exhaust system is a relatively large percentage of the exhaust volume, which is on the order of about 6 cubic feet per minute.

However, when the automobile is in high speed operation, such as in freeway driving at about 65 miles per hour or more, the hydrocarbon and carbon monoxide content of the exhaust is relatively low, so that the excess air added to the exhaust need ,be only a very small percentage of the exhaust volume'to perform its function of oxidizing these small percentage components. In the present example, with the engine in properly regulated condition, the amount of added air required is only from about 2 to 3 cubic feet per minute at high speeds. Under such relatively highspeed operation, the volume of exhaust gases may exceed cubic feet per minute. If quantities of air in excess of about 3 cubic feet per minute are added, then the excess air serves no beneficial function of oxidizing unwanted exhaust components, but does have a detrimental efiect of cooling the catalytic converter.

At the time of high speed operation the exhaust gases, undiluted with cold .air, will reach 1200 F. to 1300" F. temperature, and with about 2 cubic feet per minute of injected air will be quenched to about 1150 F. Larger amounts of air would reduce the temperature proportionally. At the time of this high speed operation, it is not important that the temperature be abnormally high because hydrocarbon and carbon monoxide contents are down close to acceptable quantities. However, if at such time air is added to the exhaust stream to give a temperature of about 850 F. to 900 F., then when deceleration, idle or heavy acceleration follows, and hydrocarbon and carbon monoxide quantities are accordingly both raised to a relatively high level, the catalyst temperature in the catalytic converter (particularly if the converter has been used on the road for an extended period) would be too low to spontaneously ignite the carbon monoxide, which is actually the highest source of burning heat. Since the exhaust gases under deceleration or idle are down at a temperature of only about 400 F., the catalyst bed without the benefit of the burning carbon monoxide would then rapidly cool and the exhaust gases would not be properly treated.

This problem of providing only a relatively small increase in the compressor output flow over a wide input speed range of the rotary power source which drives the compressor is further complicated by large variations in the exhaust pressure, and hence in the back pressure on the compressor output, such back pressure not being a direct function of the engine speed. For example, in tests wherein one of my catalytic converters was embodied in the exhaust system, where the automobile was running on the level at 40 miles per hour the back pressure was only equivalent to about 10 inches of water, while when the car was climbing a grade at full throttle at 40 miles per hour the back pressure was equivalent to about 60 inches of water, despite the fact that the engine speed was approximately the same.

Prior attempts to limit the compressor output to within the relatively narrow range required for efiicient oxidizing of the hydrocarbons and carbon monoxide in the exhaust system have included slip-clutch drives for providing rotary power to the pump, and also pump output pressure bypass valve means for diventing the flow of excess air from the pump. However, heretofore such devices have not been capable of controlling the output to within the required narrow range or of keeping the effects of i .for the-pump.

. V '3 back pressure variations from causing substantial unwantedchanges in the amount of air provided by the compressor to the exhaust line. 7

in view of the foregoing and other problems in the art,

it is an object of the present invention to provide a novel air compressor and means for regulating the output therefof whereinthe air ,output rate will increase only a relatively small amount forla relatively large increase in the speed of a rotary power source driving the pump.

Another object of the present invention is to provide anair compressor-regulator combination which will not only have an output .air flow rate that increases within relatively narrow limits for relatively wide increases in "the speed of a rotary power source driving the compressor, but which is also relatively immune from large varia- =tions in back-pressure loading on the pump output.

- A further objectof the present invention is toprovide a novel air pump and means for regulating the output thereof which have particular utility ;in combination with anti-smog apparatus associated with an internal combustion-engine for oxidizing unburned hydrocarbon and car- I -It is'also an object of the present invention to provide output regulating-means for' an air compressor of the "character described which includes a regulator valve associated with the pump inlet and having a floating valve element that rests in a lowermost position at low pump speeds permitting relatively free flow of inlet air to the pump, and which rises upon a predetermined inlet flow rate to an uppermost position Wherein the floating valve element provides a restricted inlet orifice which limits the a volume of air pumped upon further "increases in the [pump speed. a

Another object of the' -invention is to provide an air pump of the character described having air flow regulating means associated therewith which combines an inlet "regulator valve having a floating valve element with a, slip-clutch drive connection between the internal combustion engine and the pump shaft, the slip'clu-tch having a minimum of slippage at low engine speeds and 'considerfable slippage at relatively high engine speeds, this combined regulating means being eifective to limit the air outflow of the pump to within-a desired narrow increase for large increases in engine speed, with a minimum of effect fromexhaust back pressure.

Further objects and advantagesof thiepresent invention will appear during the course of'the following part of the specification wherein the details of construction and scribed reference to the accompanying drawings,,in

' no.2 looking "from 1m to right in FIG. 2.

'FIG. 4 is an end elevation View of theair pump looking from-right to left in FIG. 2.

FIG. 5 is an'axial vertical section taken on the line, .55 in FIG. 4 showing the internaldetails of construction of the pump. 1

, PEG. 6 is a cross-sectional view' taken on the line 6 -6 I of FIG. 5 showing details of the slip-clutch assembly.

FIG. 7 is a cross-sectional view along th'eline'7-7 in l PEG. 5 showing-detailsof the pump in'the region of the I pump cavity. a

FIG. :8 iso vertical section .illustratingithe details of construction of my presently preferred regulator valve engine air filter 18 to the pump inlet.

Referring to the drawings, in FIG. 11 have illustrated air pump or compressor 19 as operatively connected to a conventional internal combustion engine 12, pump 10 being driven by the engine fan belt 14'. Although pump 10 is shown as heing'driven off of the inside of the fan belt, it may be driven by either .the inside or the outside of the fan belt, and may, if desired, be conveniently mounted on a vehicle generator which is likewise driven by the fan belt 14.

Fresh air is provided to the pump inlet port through an air inlet conduit 16, which preferably extends from the Inlet conduit 16 may, if desired, comprise a plastic hose. By thus taking the fresh air from the .air filter, pump noise is substanhon-monoxide components of the engine exhaust, the compressor output being connected to the exhaust system '-to provide fresh air to assist in the oxidation.

tiaily eliminated and filtered air is fed to the pump unit. only a very minor vacuum is caused by the air filter and the inlet conduit 16 so that the fresh air provided to the pump is substantially at atmospheric pressure. The air check valve'may he provided immediately adjacent to or :as apart of the air pump it), and may comprise'a diaphragm of neoprene :or flexible plastic with a valve base or seat upstream of the diaphragm comprising a part of the pump discharge port. The downstream side 'of this diaphragm is-connected to output conduit 22 at a properly shaped fitting which is easily removable for replacing-.orinspecting the-conduit 22.

The pump output conduit 22 may, if desired, comprise copper tubing, an internal diameterfor such tubing of about of an inch appearing to be adequate for this conduit. Alternatively, the output conduit '22 may be Q a FIG. l of the drawings illustrates the embodiment of air 7 mode of operation of a preferred embodiment are deat least partly composed of plastic hose from the air pump 10 to a point closely approaching the entrance to exhaust pipe 24, with metal forming .the portion of output conduit 22 immediately adjacent to the exhaust pipe. With this construction, in :case of failure of lthfi check valve 28,'the plastic hose will melt, and discharge any hot exhaust gases, thereby protecting both the compressor and the check valve.

pump it) in connection with an internal combustion engine employing the catalytic converter system shown, described and claimed in mysaid copending application Serial No.

' 27,721. In this arrangement, catalytic case .36 is operatively conn'ected to the exhaust pipe EAat the front end of case 39, with the decontaminated exhaust gases pasS- ing out of the rearend of converter case .30 and through tail pipe 32. Spark plug 34 is disposed in the exhaust line just ahead of .thecatalytic converter case 30 for direct ignition of theexhaust-air mixture prior to the catalytic oxidation in converter case 36, this direct ignition not only accomplishing part of the oxidation of the unburned hydrocarbons and carbon monoxide inthe exhaust stream,

hut-also heating .up the exhaust gases to a point where the catalyst in the converter'case 36 will function most efficiently. The required high voltage interrupted electricity for spark .plugfidisprovided by spark coil 36 through a suitable electrical conductor 38, the primary current for coil 36 being interrupted as required by suitable interrupter points 49 which are preferably mounted on air-pump t0 ;air outputof pump 19 which will restrict the increase in the air output of the pump to a relatively small amount for relatively large increases in engine speed, so :that the a air output of pump will closely match the air requirements of the catalytic converter system. Thus, in the example previously given, for engine idle speeds of about 450 r.p.m., the converter system requires between about 1%. and 2 cubic feet of air per minute, While at highway speeds of the order of 65 miles per hour and above, when the engine is rotating at about 2500 rpm. or faster, the air requirement is only between about 2. and 3 cubic feet per minute (these figures being for a 235 cubic inch displacement engine such as a Chevrolet 6 cylinder engine, with larger displacement engines requiring proportionally more air). In order to accomplish this desired regulation of the air output of pump 10, I have found it preferable to combine two control devices with the air pump, namely, (1) the slip-clutch best shown in FIGS. 5 and 6 of the drawings, and- (2) the regulator valve best shown in FIGS. 2 and 8 of the drawings.

The slip-clutch drive employed in pump 19 has the desirable characteristic of greatly increased slippage with increases in engine speed, thereby maintaining only a small increase in pump air output at high speeds over that atlow speeds Also, this slip-clutch drive, by permitting only a small amount of increase in the pump speed for .high engine speeds as compared with the'jpump speed e for low engine speeds, keepsthe pump operating within a speed range which involve a minimum'of wear and tear in the pump, and will actually prevent rotor blade breakage, pump speeds above 4980 rpm. usually hearing or broken blade, the slip-clutch will continue to run and the belt and pump pulley will function normally; where otherwise something must give away, which would result in a burned-out belt or further damage to the pump.

It has been found in practice, however, that the slip drive for the pump, when adjusted so as to rotate the pump at a speed which will not cause blade breakage or undue wear, will produce pump air deliveries ranging from about 2 cubic feet per minute at engine idle speeds to about 5 /2 cubic feet per minute at high speeds, which is somewhat higher than the air output for optimum catalytic converter operation. It has also been found that the slip drive is to some extent susceptible to exhaust pressure changes, increases in that pressure increasing the load on the pump vanes, resulting in increased slippage in the drive.

By combining the regulator valve 20 in the pump unit, however, I have been able to control the output to the desired range of from about 1.5 to 2 cubic feet per minute at idle to about 2 to 3 cubic feet per minute at high speeds, and I have satisfactorily isolated the pump performance from variations in the back pressure.

Referring now to the specific details of construction of the pump, the pump 10 includes a suitable base member 42 upon which a pair of spaced

end plates

44 and 46 are mounted by means of bolts 48 or other suitable means. A cylindrical pump case 50 is supported between

end plates

44 and 46 by screws 52 to provide a sealed pumping chamber therein.

Pump inlet port 54 is provided through end plate 46, and is operatively connected to regulator valve 20 through a tubular connector 56. Outlet port 58 is likewise provided through end plate 46, and communicates with the outlet conduit 22. I

It will be noted that by providing inlet and

outlet ports

54 and 58, respectively, in the end wall rather than in the cylindrical pump case as is the usual procedure, I

V greatly reduce frictional wear of the ports, and on the pumping vanes, as the ports are not in the area of centrifugally forced engagement of the vanes against the pump case. Y

Pump shaft 60 is rotatably mounted in sealed antifriction bearings 62 which are supported in the

respective end plates

44 and 46,

6 V and pump rotor 64 is keyed to shaft 60 within pump case 50 between

end plates

44 and 46 so as to rotate with shaft 60. Pumping vanes 66 are radially slidably mounted in rotor 64 so as to be engaged in sliding contact with the inner Wall of pump case 50 by centrifugal force.

The pump shaft 60 is driven through a circular clutch plate 68 that is mounted on a threaded spindle 70 on one end of pump shaft 60, plate 68 being held in position by nut 72.

Clutch plate 68 is disposed Within a clutch housing 74 I which is driven by the'engine fan belt 14, housing 74- including a pulley portion 76 having an external annular recess '78 therein for receiving the fan belt 14. Clutch housing portion 76 is rotatably mounted on an anti-friction bearing 84) which is supported on a fixed hub 82 extending outwardly from end plate 44 and which is retained on hub 82 by a suitable retaining ring 83. The pulley portion 76 is tapped in several locations near the periphery to accept screws which clamp and retain the remainder of clutch housing 74 to pulley portion 76.

' Clutch housing '74 also includes an intermediate housing member 84 and a housing cover member 66, the

cover member 86 preferably being finned for cooling purposes and including an axial cup or tbimble portion 88 having a grease reservoir 90 therein. Upon rotation of the clutch housing 74, grease disposed therein frictionally engages the clutch plate 68 so as to rotate clutch plate 68 and pump shaft 66. A combination of a proper grease in clutch housing 74 and a clutch plate 68 of the particular construction shown in the drawings and herecircularly arranged openings 92 therethrough, preferably six in number, the openings 2 preferably being spaced at equal radial distances from the center of'clutch plate 68. A channel recess 94 extends from each opening 92 to the periphery of clutch plate 68 on one side of clutch plate 68, the recesses 94 extending to a depth of approximately one-third the thickness of the clutch plate. Similar'channel recesses 96 on the other side of clutch plate 68 extend from the respective openings 92 to the periphery of the clutch plate. The channel 94 from each opening 92 will overlap the channel 96 from an adjacent 'opening 92, but the channels will not break out into each 68 through the

channels

94 and 96, utilizing the larger clearance between the outer edge of clutch plate 68 and clutch housing 74 as a reservoir for the grease in transit, limiting the tendency to increase frictional engagement at this point during high speed operation. 7

A high temperature silicone grease has been found satisfactory for use in the clutch housing, providing an increase of from about 1 /2 to 2 cubic feet per minute to about 5 cubic feet per minute of pump air output for an engine speed range of from about 450 r.p.m. (idle speed) to 2500 rpm. (highway speed), where the pump is operated without the benefit of the regulator valve 241'.

- Variations in this relationship between pump air output have a characteristic of thixotropy; that is, one which will function principally as asolid until a certain shear] point is reached, and thereafter will function primarily as a liquid. Silica .which is powdered to a fineness of lessthan 1 micron in particle size exercises this property 7 a when mixed with a suitable carrier liquid such as water or oil. Other materials which will perform in this mannet are finely powdered eantocel produced by Monsanto Chemical Company and finely powdered Kaolirf produced by Minerals and Chemicals Corporation.

Finely powdered silica appears tob e preferred as it does' not 'attrite by grinding itself, Alsovery small concern ftrationsiof Guar, such as Jaguar, a commercial gum resin, willQpromote thixotropy, so that small quantities of such material'may be employed.

' Iffind it convenient to mount the interrupterpoints 40 on -the outside of pump end plate 46, and toprovide a 'multi-lobed cam member 98 on the end of pump shaft 7 60 which projects outwardly through end plate 46 for producing the vibratory motion required for the interrupter points 4d The points '40 include a movable contact member 1th and a fixed contactrmeflmber 1ti2,'the

mov able contact member 1% being spring-biased against esired interruption enabling the coil .to then step-up the primary voltage to a secondary voltage snfilcient to'fire the ignition spark plug 34+. A typical installation would find fixed contact member 162 electrically grounded to pump end plate .46, and movable contact member 100 insulated from end plate 46 and connected externally to the primary coil winding. A capacitor may be used across interrupter points 40 if desired, both for the elimination of metal transfer andifor the more satisfactoryoperation of the ignition system which includes the spark plug 34. Referring to FIGS. 2 and 8 of the drawings, I will now describe a presently preferred -.ernbodiment of the regulator valve which cooperates with the slip-clutch drive to provide the desired air output of the pump. 7

' The regulator valve includes a vertically arranged :tubular valve housing 104 which is preferably supported on the pump casing as by means'of 'a supporting bracket i 106 that extendsaround valve. housing 104 and is .at-

cached to pump end plate 46 by one or more screws 193. The regulator valve 20 includes a bottom end closure 110 which extends across the lower end oftubular valve housing 104, with valve inlet port 112 extending through bottom end closure i110 and communicating with a suitable inlet fitting 1 14 attached to end closure 110. The air inlet conduit 16'is operatively connected to inlet fitting 114 by conventional means.

. .8 valve housing 104 through outlet port '122 and fitting '124, and then will pass through tubular connector 56 to the pump inlet 'port. 54 p A wall 126 extends across valve housing 164 below outlet port 122,'the walli126 being provided with an orifice 128. An adjusting screw 135} is threadedly mounted in top end closure 12d, extending downwardly through valve .orifice 128; By this means, when the air how increases beyond a certain minimum flow, it will blow the floating ball valve element 118 upwardly until valve element 118 isstopped by the lower end of adjusting screw 13%. The ball will remain in this'position so as :to

define a more restricted valve orifice until'the .air flow drops below the said predetermined minimum flow, at which time the ball will again fall down against the screen 116, removing the restriction from valve orifice 123.

In the example previously given, where the desired pump output ranged from about 1% to' 2 cubic feet per minute at idle engine speeds to between 2 and 3 cubic feet per-minute at highway speeds, the relative sizes of the ball valve element 118 and the tubular valve housing 104 are preferably!suchfthatiwhen the input ,air flows at 2 cubic feet per niinute or less, the valve element 1-18 will rest on screen spacer .116;at the bottom of tubular -housing illa, butwhen the airflow rateincreases to in ,7 excess ofr2 cubic feet per minute, "the ball valve element 118 will rise and be air-borne, seating againstthe bottom of adjusting screw 13 adjacent valve orifice 128. The

ill

Disposed across the inside of valve housing 14M above; "bottom end closure 110 is ascreen spacer member 1 16 upon which a floating valve. element 118 normally rests.

Valve element 1181s preferably of the ball type, and is suitably smaller than the inside .diameter of valve housing-104. The valve element .118 is spaced sufiici ently above inlet port 112'by 'thewscreen 11 6 to permit incoming air to pass .freely tbroughvportyllz and around valve element 11-8 upwardly through valve housing 104 when ball valve element 118 is in its lowermost, rest position against screen 116. It will be apparent that other suitable spacer means may be provided in place of the "Atop end closure'member '120 completely closes off for attachment of theoute're'rid of tubular connector 56, whereby valve outlet air willlpass' out of the uppere of 1 screen 116, which is merely the presently preferred means v for this purpose.

ball "valve element 118 will remain in this position until the air flow again decreases to below about 2 cubic feet per minute, at which time the ball will drop down against screen 116 and orifice 128 will be unrestricted.

I have found in practice that by properly adjusting the screw 130, the ball valve element '118 can be positioned relative to orifice 128 so as to control the air flow to only slightly in excess of 3 cubic feet per minute at high engine speeds. The compressor at high speeds, in effect, isunder a partial vacuum or suction which variesv from substantially'zero at 2 cubic feet per minute to higher vacuums as the speed is increased. Back-pressure loading upon the compressor from the'engine appears .to have no .eltect upon the airdelivery of the compressor ,to the exhaust system above 2 cubic feet .per minute, -as such back pressure only afiectszthe degree of clutch slippage, which 2 /2 cubic feet per minute air flow merely affects the amount of suction at the pump inlet.

While the instant invention has been shown and described herein in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the .detailsdisclosed herein, but is to be accorded the full scope of ,theclaims.

1. Apparatus for removing impurities from an internal combustion engine exhaust system which comprises: an exhaust conduit; means in said exhaust conduit for oxidizing exhaust ingredients not previously oxidized .in the engine; and air injection'means connected to said exhaust conduit for introducing air into said exhaust conduit to provide a mixture of air and exhaust ingredients, said air injection means including an air pump havinga housing with air .inlet and outlet ports, a rotor member rotatably mounted in the housing for drawing air in through said inlet port and pumpingthe air out through :said outlet port, rotary power input'means rotatably mounted in the housing and connected to ,the rotor for driving the rotor, and an airflow regulator valve connected to said pump inlet port, said regulator valve including a body having a passage therein, an air inlet opening and anair outlet orifice in the bodycommunicating with said passage, air conduit means connecting the orificeto the pump inletport, a valve element of smaller d a closed position adjacent to said orifice in which the valve element partially restricts the orifice, said valve element being normally biased toward its said open position, whereby when the flow of pump input air through said valve is below a predetermined rate the valve will be in its open position and the air will have relatively unrestricted passage through the valve, and when the flow of pump input air is above said predetermined rate the air will blow the valve element to its said closed position at which the valve element will restrict the flow of air through the orifice.

2. Apparatus as defined in claim 1 wherein saidoxidiz ing means includes direct ignition means in said exhaust conduit downstream of said air injection means for igniting exhaust ingredients not previously completely oxidized, and catalytic oxidizing means connected to said exhaust conduit downstream of said direct ignition means for oxidizing exhaust ingredients not previously completely oxidized.

3. Apparatus as defined in claim 2 wherein said connection between said rotary power input means and said rotor is a slip-clutch drive connection.

4. Apparatus as defined in claim 3 wherein said rotary power input means comprises a clutch housing rotatably mounted on the pump housing, and said slip-clutch drive connection includes a clutch plate within said clutch housing, said clutch plate being connected to the rotor so that the clutch plate and rotor rotate together; and thick fluid material in the clutch housing for imparting rotation from the clutch housing to the clutch plate.

5. Apparatus as defined in claim 4 wherein said biasing is accomplished by vertical arrangement of said passage with said inlet opening communicating with the passage below said orifice, the valve element being urged by gravity toward its said open position.

6. Apparatus as defined in claim 5 wherein said valve element is a ball loosely disposed in said passage.

7. Apparatus as defined in claim 4 wherein said thick fluid has the characteristics of thixotropy.

8. Apparatus for removing impurities from an internal combustion engine exhaust system which comprises: an exhaust conduit; means in said exhaust conduit for oxidizing exhaust ingredients not previously oxidized in the engine; and air injection means connected to said exhaust conduit for introducing air into said exhaust conduit to provide a mixture of air and exhaust ingredients, said air injection means including an air pump having a housing with air inlet and outlet ports, a rotor member rotatably mounted in the housing for drawing air in through said inlet port and pumping air out through said outlet port, rotary power input means rotatably mounted in the housing and connected to the rotor for driving the rotor, and an airflow regulator valve connected to said pump inlet port, said regulator valve including abody having a passage therein, an air inlet opening and an air outlet orifice in the body communicating with said passage, said passage extending upwardly from said inlet opening to said orifice, air conduit means connecting the orifice to the pump inlet port, a valve element of smaller cross-section than said passage disposed in said passage and movable between a lowermost position spaced above said inlet opening and an uppermost position adjacent to said orifice in which the valve element partially restricts the orifice, abutment means in said passage against which the valve element seats in its lowermost position, and stop means adjacent to said outlet orifice against which the valve element seats in its uppermost position, whereby when the flow of pump input air through said valve is below a predetermined rate the valve will be in its lowermost position and the air will have relatively unrestricted passage through the valve, and when the flow of pump input air is above a predetermined rate the air will blow the valve element to its uppermost position at which time the valve element will restrict the flow of air through the orifice.

9. Apparatus as defined in claim '8 wherein said abutment means is a wire screen extending across said passage above said inlet opening.

10. Apparatus as defined in claim 6, wherein'said pasternal combustion engine exhaust system which cornprises: an exhaust conduit; means in said exhaust conduit for oxidizing exhaust ingredients not previously oxidized in the engine; and airinjection means connected to said exhaust conduit for introducing air into said exhaust conduit to provide a mixture of air and exhaust ingredients, said air injection means including an air pump having-a housing with air inlet and outlet ports, a rotor member rotatably mounted in the housing for drawing air in through said inlet port and pumping air out through said outlet port, rotary power input means rotatably mounted in the housing; a slip-clutch drive connection in the pump between said power input member and the rotor, and an airflow regulator valve connected to said pump for regulating the rate of flow of air pumped through said outlet port, said regulator valve including a body having a pas sage therein, an air inlet opening and an air outlet orifice in the body communicating with said passage, air conduit means connecting the orifice to the pump inlet port, a

valve element of smaller cross-section than said passage disposed in said passage between said inlet opening and said orifice, and movable between an open position spaced from said orifice and a closed position adjacent to-said orifice in which the valve element partially restricts the orifice, said valve element being normally biased toward its open position, whereby when the flow of pump input air through said valve is below a predetermined rate the valve will be in its open position and the air will have relatively unrestricted passage through the valve, and when the flow of pump input air is above said predetermined rate the air will blow the valve element to its said closed position at which time the valve element will restrict the flow of air through the orifice.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

1. APPARATUS FOR REMOVING IMPURITIES FROM AN INTERNAL COMBINATION ENGINE EXHAUST SYSTEM WHICH COMPRISES: AN EXHAUST CONDUIT; MEANS IN SAID EXHAUST CONDUIT FOR OXIDIZING EXHAUST INGREDIENTS NOT PREVIOUSLY OXIDIZED IN THE ENGINE; AND AIR INJECTION MEANS CONNECTED TO SAID EXHUSTED CONDUIT FOR INTRODUCING AIR INTO SAID EXHAUST CONDUIT TO PROVIDE A MIXTURE OF AIR AND EXHUSTED INGREDIENTS, SAID AIR INJECTIONS MEANS INCLUDING AN AIR PUMP HAVING A HOUSING WITH AIR INLET AND OUTLET PORTS, A ROTOR MEMBER ROTATABLY MOUNTED IN THE HOUSING FOR DRAWING AIR IN THROUGH SAID INLET PORT AND PUMPING THE AIR OUT THROUGH SAID OUTLET PORT, ROTARY POWER INPUT MEANS ROTABABLY MOUNTED IN THE HOUSING AND CONNECTED TO THE ROTOR FOR DRIVING THE ROTOR, AND AN AIRFLOW REGULATOR VALVE CONNECTED TO SAID PUMP INLET PORT, SAID REGULATOR VALVE INCLUDING A BODY HAVING A PASSAGE THERIN, AN AIR INLET OPENING AND AN AIR ORIFICE IN THE BODY COMMUNICATING WITH SAID PASSAGE, AIR CONDUIT MEANS CONNECTING THE ORIFICE TO THE PUMP INLET PORT, A VALVE ELEMENT OF SMALLER CROSS-SECTION THAN SAID PASSAGE DISPOSED IN SAID PASSAGE BETWEEN SAID INLET OPENING AND SAID ORIFICE, AND MOVABLE BETWEEN AN OPEN POSITION SPACED FROM SAID ORIFICE AND A CLOSED POSITION ADJACENT TO SAID ORIFICE IN WHICH THE VALVE ELEMENT PARTIALLY RESTRICTS THE ORIFICE, AND SAID VALVE ELEMENT BEING NORMALLY BIASED TOWARDS ITS SAID OPEN POSITION WHEREBY WHEN THE FLOW OF PUMP INPUT AIR THROUGH SAID VALVE IS BELOW A PREDETERMINED RATE THE VALVE WILL BE IN ITS OPEN POSITION AND THE AIR WILL HAVE RELATIVELY UNRESTRICTED PASSAGE THROUGH THE VALVE, AND WHEN THE FLOW OF PUMP INPUT AIR IS ABOVE SAID PREDETERMINED RATE THE AIR WILL BLOW THE VALVE ELEMENT TO ITS SAID CLOSED POSISTION AT WHICH THE VALVE ELEMENT WILL RESITRICT THE FLOW OF AIR THROUGH THE ORIFICE.