March 14, 1967 K. M. SNIDER 3,308,798
METERING VALVE FOR CRANKCASE VENTILATION SYSTEMS Filed May 5, 1965 2 Sheets-Sheet 1 INVENTOR KENNETH M. SN/DER ATTORNEYE March 14, 1967 sNlDER 3,308,798
METERING VALVE FOR QRANKCASE VENTILATION SYSTEMS Filed May 5, 1965 2 Sheets-Sheet 2 Fly F 17 INVENTOR KENNETH M SN ATTORNEYZQ United States Patent Ofilice 3,308,798 Patented Mar. 14, 1967 3,308,798 METERING VALVE FOR CRANKCASE VENTILATION SYSTEMS Kenneth M. Snider, 227 Walter Ave, Mansfield, Ohio 44903 Filed May 5, 1965, Ser. No. 453,340 7 Claims. (Cl. 123-119) This invention relates generally to improvements in metering valves and more particularly to metering valves of the type used in the manifold vacuum system of crankcase ventilation of internal combustion engines.
Crankcase ventilation is of prime importance in controlling of sludge and keeping the lubricating system of an internal combustion engine in good condition. Ineffective or inoperative crankcase ventilators are responsible for lubricating troubles serious enough, in some cases, to cause engine failure. Two methods of crankcase ventilation are presently in use, the road-draft system and the manifold vacuum system.
In the road-draft system of automobile crankcase ventilation, vapors developed in the crankcase are vented exteriorly of the engine, being one of the elements which contribute to the smog conditions which have become increasingly prevalent.
In order to control smog, the road-draft system of automobile crankcase ventilation has been outlawed in some States and the manifold vacuum system of crankcase ventilation has become mandatory. The correct operation of the manifold vacuum system depends upon a free flow of air through the oil filler tube and engine to the control valve mounted on the intake manifold. The system sucks crankcase vapors into the intake manifold to be burned in the combustion chamber. The flow of the vapors is controlled by a ventilator metering valve which must be adjusted so that the high vacuum at engine idle and deacceleration provides minimum ventilation, and the low vacuum at conventional road speeds provides maximum ventilation. The valve must also be constructed so that upon backfire of the engine the crankcase is closed so that it will not receive the backfire from the intake manifold.
Previously provided metering valves of this type have relied upon various forms of spring tension for the re quired operating characteristics and have been susceptible to clogging with carbon or other foreign matter so that the the ventilation system does not operate properly. This inoperative condition causes pressure to build up in the crankcase which may cause oil leakage at the rear main bearing or by the piston rings.
The primary object of this invention is the provision of an improved metering valve for use in crankcase ventilation systems of the manifold vacuum type.
A further object is the provision of a metering valve having self cleaning characteristics whereby sludge or residue which may be deposited by the material passing therethrough will be agitated in such a manner as to prevent an accumulation thereof in the metering valve.
A further object is the provision of a metering valve which may be readily calibrated according to the cubic inch displacement of the engine with which the same is to be used, for more efiicient operation thereof.
Other objects and advantages of the invention will be apparent during the course of the following detailed description, taken in connection with the accompanying drawings, and in which drawings:
FIG. 1 is a diagrammatic view showing my improved metering valve as a part of the manifold vacuum system of an internal combustion engine.
FIG. 2 is an exploded perspective of my improved metering valve.
FIG. 3 is a transverse sectional view of the metering valve, showing the same under normal operating conditions in the manifold vacuum system of crankcase ventilation.
FIG. 4 is a view similar to FIG. 3 showing the valve under operating conditions of idling or deacceleration of the internal combustion engine.
FIG. 5 is a view similar to FIG. 3 showing the valve under operating conditions of backfire of the internal combustion engine.
FIGS. 6, 7, and 8 are transverse cross sectional views of the diaphragm of my improved metering valve, showing calibration thereof according to the cubic inch displacement of the internal combustion engine with which the metering valve is to be used.
FIGS. 9, 10, and 11 are bottom plan views of the diaphragm of my improved metering valve, showing calibration of the passageways therethrough which may be made in accordance with the cubic inch displacement of the internal combustion engine with which the metering valve is to be used.
FIG. 12 is a transverse cross sectional view of a modified form of my improved metering valve.
In the drawings, wherein for the purpose of illustration are shown preferred and modified embodiments of the invention, and wherein similar reference characters designate corresponding parts throughout the several views, the letter A may generally designate an internal combustion engine; B my improved metering valve as shown in FIGS. 1-11; and C the modified form of metering valve as shown in FIG. 12.
Internal combustion engine A is shown as including acrankcase 15 having an oil filter tube 16 provided with a ventilated cap 17 which permits substantially free flow of air through the crankcase. The flow of air through the crankcase is illustrated by the arrows in FIG. 1. A car buretor 18 having anair cleaner 19 is mounted on the engine. The carburetor 18 discharges into the intake manifold 20. Amanifold suction tube 21 is interconnected at one end to crankcase 15 and at the other end to intake manifold 20, completing the circuit for crankcase ventilation. Metering valve B is mounted at an appropriate location inmanifold suction tube 21, depending on space limitation adjacent the engine.
It should be noted that although metering valve B is shown herein as used in association with the manifold vacuum system of crankcase ventilation of an internal combustion engine of the gasoline type such as used in automobiles, the same could likewise be used in crankcase ventilation of virtually any type of internal combustion engine in which it might be desirable to provide crankcase ventilation. Likewise, although the metering valve has been developed primarily for use in connection with crankcase ventilation, it could be used for other purposes, such as the metering of additives to the intake manifold of an internal combustion engine.
Metering valve B preferably includesvalve case 25 anddiaphragm 26.
Valve case 25 may be of any appropriate material. It may, for instance, be molded from a synthetic resin which is resistant to the material moving through the valve, be a cast or molded metal, or be machine tooled. Valve B, as herein shown, is molded from a synthetic resin having suitable characteristics for resistance to the material to be conveyed through the valve.
Valvecase 25 preferably includes anupper section 28 andlower section 29.Upper section 28 includes a substantially bell shapedmember 30 at one end thereof hav- As shown in FIGS. 3, 4 and 5, the valve.
case is assembled by snappingflange 33 withingroove 31 to provide aunitary valve case 25. This construction pro- 'vides for facile opening ofvalve case 25 in the event it proves necessary to clean the interior of the same and for facile removal ofdiaphragm 26 therefrom.
Attachment of disc-like plate 32 to substantially bell shapedmember 30 provides avalve case 25 having achamber 34 including anintake face 35,outlet face 36opposite intake face 35, and aside wall portion 37 at the outer periphery of and extending betweenintake face 35 andoutlet face 36. Disc-like plate 32 is provided with anintake conduit coupling 38 having aport 39 opening intochamber 34 at theintake face 35 thereof. Substantially bell shapedmember 30 is provided with anoutlet conduit coupling 40 having 'aport 41 opening int-o chamber 34 at theoutlet face 36 thereof.Outlet port 41 may have aportion 42 of an enlarged internal diameter adjacent the opening thereof intochamber 34, for cooperation Withdiaphragm 26, as will be subsequently described. Valve seat 45 is provided inchamber 34adjacent port 39 andvalve seat 46 is provided inchamber 34adjacent port 41,valve seats 45 and 46 cooperating withdiaphragm 26 in sealing of their respective adjacent ports, as will besubsequently described.
Outlet face 36 is perfer'ably substantially concave fromside wall portion 37 to an apex atvalve seat 46. The purpose of this concavity will be subsequently described.
Diaphragm 26 preferably includes a disc-like body portion 50 having acentral body portion 51, a plurality ofpassageways 52 being provided inbody portion 50 aboutcentral body portion 51, andcentral body portion 51 including a normally closed valve means 53.
The term disc-like has been used herein in view of the fact that it descriptively portrays the form of body portion illustrated. It is, however, to be understood thatbody portion 50 may have any appropriate configuration, according to the configuration ofchamber 34 within which the same interfits, the descriptive phrase disc-like, being used merely as a matter of illustrative convenience.
As shown in FIGS. 3, 4 anddiaphragm 26 is mounted inchamber 34 with theouterperiphery 55 thereof positionedadjacent sidewall portion 37 for reciprocable abutment therewith asdiaphragm 26 moves betweenintake face 35 andoutlet face 36 ofchamber 34.Side wall portion 37 comprises means for guiding reciprocable movement ofdiaphragm 26 and the abutment ofperiphery 55 therewith comprises means for wiping residue deposits fromside wall portion 37. As shown in FIG. 3,passageways 52 open fromintake face 35 tooutlet face 36 so that whendiaphragm 26 is disposed inchamber 34 as shown in FIG. 3, material may flow through the metering valve throughport 39,passageways 52, and out throughport 41.
Central body portion 51 is juxtaposed for sealing abutment withvalve seat 46 under one condition of flow through the metering valve, as shown in FIG. 4, and for sealing abutment with valve seat 45 in another condition of flow through the metering valve, as shown in FIG. 5. This relationship will be further described in connection with the operation of the metering valve.
Valve means 53 is of the type which includes means opening intoport 41 for permitting a substantially restricted flow of material throughport 39, valve means 53 andport 41 when the flow through the metering valve is as shown in FIG. 4, as will be subsequently more fully described in connection with the-operation of the metering valve. As shown in the drawing, valve means 53 is of the heart valve type including anipple 58 having an elongated slit 59 at the terminal end thereof. Operation of valve means 53 will be subsequently more fully described.
As shown in the drawings,jport 41 has been provided with an enlargedportion 42 into which is' receivednipple 58 of normally closed valve means53 ofdiaphragm 26. It is, of course, to be understood that the entire length ofport 41 could be such as to op'erably receivenipple 58 of valve means 53.
FIGS. 3, 4 and 5 show various operating positions of metering valve B in the intake manifold line of an internal combustion engine. The metering valve is mounted in the intake manifold line withport 39 opening to that portion of the line leading to the crankcase to be ventilated, andport 41 opening to that part of the line leading to the intake manifold. A vacuum is thus created by the intake manifold throughport 41 tochamber 34. Under normal operating conditions of the internal combustion engine of an automobile, a relatively low vacuum, usually of from 6 to 8 inches of mercury, will be created throughport 41. Under such low vacuum conditions,diaphragm 26 is maintained at an intermediate range of reciprocable movement betweenintake face 35 and outlet face 360f chamber 34, as shown in FIG. 3. Under theseop'ersnng conditions, vapors from the crankcase will flow throughport 39, throughpassageways 52, and out through port41 to the intake manifold. When the internal combustion engine is idling, or under conditions of deacceleration of the internal combustion engine, a relatively high vacuum, usually of from 12 to 16 inches of mercury, will be created in the intake manifold, exerting this higher vacuum throughport 41 tochamber 34. When this condition of high vacuum occurs,diaphragm 26 will be sucked up so that thecentral body portion 51 thereof in sealing abutment withvalve seat 46, as shown in FIG. 4. Whenport 41 is thus sealed atvalve seat 46, increased pressure is exerted on normally closed valve means 53, which acts to open slit 59 ofnipple 58 of valve means 53, permitting a relatively restricted flow from the crankcase throughport 39, throughvalve 53, and out throughport 41 to the intake manifold.
In the event that the internal combustioneng ine back= fires, flame or sparks are likely to occur in the intake manifold. If such combustion is permitted to reach the crankcase, the crankcase might Blew up, Accordingly; under such conditions of backfire, as shown in FIG. 5, the force or the backfire entering en 41 win force are phragm 26 down towardintak'e race 35 sttangential body portion 51 thereof abuts against valve seat 45, sealing oif communication with the crankcase. f
In the use of the manifold vacuum system or crankcase ventilation, the mixture of the intake manifold musics adjusted to receive the crankcase vapors. Since my im proved metering valve is designed to be used (in iiit'einal combustion engines of various cubic inch displacement;diaphragm 26 thereof is preferably calibrated to provide optimum performance in connection with the cubic inch displacement of the internalcombustion engine with which itis being used.
As shown in FIG. 3, under normal operating conditions, thediaphragm 26 is at an intermediate range of reciprocable movement betweenintake face 35 andoutlet face 36.
Disc-like body portion 50 must therefore have sulfiicent rigidity to remain in juxtaposition, as shown in FIG. 3, for flow of vapors throughpassageways 52 thereof under normal operating conditions. If disc-like body portion 50 is too flexible, the normally low vacuum under normal operating conditions would be likely to causediaphragm 26 to be sucked to a position as shown in FIG. 4. On the other hand,body portion 50 must be suffiicently flexible so that under increased vacuum, as under idling or deaccelerating conditions, the same will flex so thatcentral body portion 51 thereof may abut withvalve seat 46, as shown in FIG. 4. The shaped concavity ofoutlet face 36 and the relative rigidity ofdiaphragm 26 thus comprise means for maintainingdiaphragm 26 at an intermediate range of reciprocable movement under normal operating conditions and the relative flexibility ofdiaphragm 26 comprises means for permitting seating thereof onvalve seat 46 under idling and deaccelerating operating conditions.
FIG. 6 shows a diaphragm which is of relatively low flexibility such as would be used in connection with an internal combustion engine having a high cubic inch displacement. The parts of the diaphragm of FIG. 6 which correspond to parts ofdiaphragm 26 have been indicated by identical reference characters, with the exponent a.
The diaphragm of FIG. 7 is of medium flexibility, such as would be utilized in connection with internal combustion engines having an average cubic inch displacement. Identical reference characters having the exponent b have been applied to the parts of the diaphragm of FIG. 7 which correspond to parts ofdiaphragm 26.
The diaphragm of FIG. 8 is extremely flexible, and would be used in connection with internal combustion engines having a low cubic inch displacement. Identical reference characters having an exponent 0 have been applied to the parts of the diaphragm of FIG. 7 which correspond to parts ofdiaphragm 26.
As previously noted, in the manifold system of crankcase ventilation, the mixture flowing through the intake manifold must be adjusted to receive vapors from the crankcase. Under normal operating conditions, an internal combustion engine having a high cubic inch displacement will be able to ingest a greater flow of crankcase vapors than would be internal combustion engine of relatively low cubic inch displacement. Accordingly, it is within the scope of my invention to provide forpassageways 52 throughdiaphragm 26 of various size and at various locations, as indicated indiaphragms 26 26 and 26 of respective FIGS. 9, 10 and 11. Identical reference characters with exponents d, e and 7 have been respectively applied to the parts of diaphragms of FIGS. 9, 10 and 11 which correspond to similar parts ofdiaphragm 26.
In normal operating conditions, the intake manifold of the internal combustion engine with which the metering valve is used will be able to ingest a greater supply of crankcase vapors than it will be able to ingest during con ditions of idle and deacceleration. Accordingly, in order that deacceleration may be evenly accomplished and in order to secure proper idling of the internal combustion engine, means must be provided for restricting the flow of crankcase vapors to the intake manifold under conditions of idling and deacceleration of the internal combustion engine.
Such restricted flow of vapors is attained by movement ofdiaphragm 26 of my improved metering valve into position as shown in FIG. 4 in which the only flow from the crankcase to the intake manifold will be regulated by that amount of vapors which are permitted to flow through valve means 53.
Metering valve C is generally the same as metering valve B, and identical reference characters with the exponent g have been applied to the parts thereof corresponding to parts of metering valve B. In some vehicles, such as trucks, which may be subjected to shock loads, etc., which are not normally encountered by the usual automobile, it may be desirable to assemble the metering valve other than by a mere snap-fit of one part to another. It may thus be desirable to provideplate 32 and the lowermost end of bell shapedmember 30 withmating screw threads 60,intake conduit coupling 38 and andoutlet conduit coupling 40 being provided with wrench receiving faces 62 for tightening of the parts to gether and unloo-sening of the same. Otherwise, construction of metering valve C is identical to that of metering valve B.
Various changes may be made to the forms of the invention herein shown and described without departing from the spirit of the invention or scope of the following claims.
I claim:
1. In a metering valve, the combination of a valve case including a chamber having an intake face, an outlet face opposite said intake face, and a side wall portion at the outer periphery of and extending between said intake face and said outlet face, an intake conduit 6 coupling having a port opening into said chamber at the intake face thereof, an outlet conduit coupling having a port opening into said chamber at the outlet face thereof, and a valve seat in said chamber at each said port; and a diaphragm mounted in said chamber for substantially free reciprocable movement between said ing of said port of said outlet conduit coupling at the other extreme of reciprocable movement of said diaphragm, and a plurality of passageways about said central 'body portion opening from said intake face of said chamber to said outlet face thereof and permitting relatively free flow through said metering valve at intermediate ranges of reciprocable movement of said diaphragm, said passageways being closed to flow therethrough by abutment of said diaphragm with said outlet face and said valve seat of said port opening thereinto when said diaphragm is at its extreme position toward said outlet face, said central body portion of said diaphragm including a normally closed valve and said normally closed valve including means opening to permit substantially restricted flow of material through said metering valve under How conditions which cause said central body portion of said diaphragm to abut said valve seat of said chamber at said port of said outlet conduit coupling.
2. The combination as specified in claim 1 wherein the outer periphery of said disc-like body portion of said diaphragm abuts said side wall portion of said chamber during reciprocable movement of said diaphragm, said side wall portion of said chamber comprising means for guiding reciprocable movement of said diaphragm, and said abutment of the outer periphery of said disc-like body portion of said diaphragm comprises means for wiping residue deposits from said side wall portion of said chamber.
3. The combination as specified in claim 1 wherein said metering valve is disposed in a pipe line for venting the crankcase of a vehicle to the intake manifold of an internal combustion engine and said passageways of said disc-like body portion of said diaphragm are calibrated according to the cubic inch displacement of the internal combustion engine.
4. The combination as specified in claim 1 wherein said outlet face of said chamber is concave from said side wall portion to an apex at said valve seat of said port of said outlet conduit coupling.
5. The combination as specified in claim 4 wherein said disc-like body portion of said diaphragm is of a flexibility 'whereby to substantially conform to the concavity of said outlet face of said chamber in the seating of said central body portion of said diaphragm on said valve seat of said port of said outlet conduit coupling.
6. The combination as specified in claim 5 wherein said metering valve is juxtaposed in a pipe line for venting the crankcase of a vehicle to the intake manifold of an internal combustion engine and said flexibility of said disc-like body portion of said diaphragm is calibrated according to the cubic inch displacement of the internal combustion engine whereby said diaphragm is maintained at an intermediate range of reciprocable movement under normal operating conditions of the internal combustion engine and said diaphragm flexes to seat the central body portion thereof on said valve seat of said port of said outlet conduit under idling and deaccel- 7 eration operating conditions of the internal combustion engine.
7. In a metering valve for use in a pipe line for venting the crankcase of a vehicle to the intake manifold of an internal combustion engine, the combination of a valve case having an intake face, an outlet face opposite said intake face, and a side wall portion at the outer periphery of and extending between said intake and said outlet face, an intake conduit coupling for attachment thereto of a conduit leading to the crankcase, said intake conduit coupling having a port opening into said chamber at the intake face thereof, an outlet conduit coupling for attachment thereto of a conduit leading to the intake manifold, said outlet conduit having a port opening into said outlet face of said chamber in juxtaposition whereby vacuum of the intake manifold acts through said outlet conduit, chamber and intake conduit in drawing fumes from the crankcase to the intake manifold, and a valve seat in said chamber at each said port; and a diaphragm mounted in said chamber for substantially free reciprocable movement between said intake and outlet face of said chamber, said diaphragm having a disc-like body portion extending substantially transversely across said chamber with the outer periphery thereof adjacent said side wall portion of said chamber and juxtaposed in said chamber to substantially freely float in said chamber at intermediate ranges of reciprocable movement thereof under normal operating conditions of the internal combustion engine, to be drawn to an extreme of reciprocable movement toward said outlet face under idling and deacceleration operating conditions of the internal combustion engine, and to be forced to an extreme of reciprocable movement toward said intake face when said internal combustion engine backfires, said disc-like body portion including a central body portion juxtaposed for sealing abutment with each said valve seat of said chamber for sealing of said port of said intake conduit coupling at the extreme of reciprocable movement of said diaphragm toward said intake face of said chamber and sealing of said port of said outlet coupling at the extreme of reciprocable movement of said diaphragm toward said outlet face of said chamber, and a plurality of passageways about said central body portion opening from said intake face of said chamber to said outlet face thereof and permitting relatively free flow through said metering valve at intermediate ranges of reciprocable movement of said diaphragm, said passageways being closed to flow therethrough by abutment of said diaphragm with said outlet face and said valve seat of said port opening thereinto when said diaphragm is at its extreme position toward said outlet face, and said central body portion of said diaphragm includes a normally closed valve, said normally closed valve including means opening to permit restricted flow of material through said metering valve at the extreme of reciprocable movement of said diaphragm toward said outlet face of said chamber.
References Cited by the Examiner UNITED STATES PATENTS 3,034,731 5/1962 C-hapin 137525.1 X 3,105,477 10/1963 Lowther 123-119 3,111,138 11/1963 Humphreys 123119 X 3,122,161 2/1964 Pfeifer 137525.1 X 3,198,208 8/1965 Tramontini 123119 X 3,241,537 3/1966 Jones a 123119 MARK NEWMAN, Primary Examiner.
A. L. SMITH, Assistant Examiner.