US 3290869 A
Abstract available in
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Description (OCR text may contain errors)
Dec. 13, 1966 E, c. LENTZ ETAL 3,290,869
BREATHER CAP Original Filed Dec. 13, 1961 2 Sheets-Sheet l Tray/vr@ Dec. 13, 1966 E. c. LENTZ ETAL 3,290,869
BBEATHER CAP Original Filed Deo, 13, 1961 2 Sheet5-511eet 2 United States Patent C 3,290,869 BREA'IHER CAP Ervin C. Leutz, Erickson, Mich., and William G. McKenare, Racine, Wis., assignors to Walker Manufacturing tornpany, Racine, Wis a corporation of Delaware @riginal application Dec. 13, 1961, Ser. No. 159,124. Divided and this application .inne 8, 1962, Ser. No.
17 Claims. (ICI. 55 417) This invention is a division of our application Serial Number 159,124, led December i3, 1961, now US. Patent No. 3,172,309.
This invention relates to internal combustion engine crankcase Ventilating systems and more particularly to an engine crankcase Ventilating system wherein crankcase vapors and gases are withdrawn from the crankcase and delivered to the engine carburetion device for delivery to the engine combusion chambers.
The vapors and gases which accumulate in the crankcase during internal combustion engine operation are commonly referred to as blowby. In general, two types of crankcase Ventilating systems have been previously proposed. In one type of system blowby is exhausted directly to the atmosphere. Such a system is commonly provided `by a road draft tube which extends downwardly from the crankcase and atmospheric air inlet means connected to the crankcase at some other point to establish a ow of air which will carry blowby out the road draft tube. The discharge of blowby to the atmosphere is undesirable because of the contaminating eitect thereof. In the other type of system, the contamination of the atmosphere by blowby is eliminated by discharging the blowby into the engine intake manifold, the air intake passage means, or some other portion of the combustion air delivery system. In such systems, the blowby is returned to the combustion chambers and consumed rather than being dumped to the atmosphere. This invention relates particularly to a crankcase Ventilating system wherein the blowby is returned to the combustion chambers rather than being discharged to the atmosphere.
It is an object of this invention to provide a Ventilating system which is relatively simple in construction and design, and therefore can be economically manufactured and easily installed.
Still a further object is to provide, as a part of the Ventilating system, a new and improved crankcase oil iiller tube breathing unit through which a ilow of air from the atmosphere to the crankcase may be established for ventilation purposes. In this regard, it is an object ot the present invention to provide oil filler tube breathing means which is readily adaptable for use with a Variety of iiller tube designs.
Still another object of the present invention is to provide an oil filler tube cap construction having new and improved air filtering and control Valve means for incorporation in a Ventilating system.
Other objects and advantages of the present invention will be apparent or become apparent by reference to the following detailed description and the accompany drawing wherein:
FIGURE l is an end elevational View, partly in section, of a conventional internal combustion engine and accessory components thereof incorporating a crankcase ventilating system in accordance with the principles of the invention;
FIGURE 2 is a partial side elevational View taken along the line 2 2 in FIGURE 1 showing a portion ofthe Ventilating system;
FIGURE 3 is a sectional View taken along the line 3 3 in FIGURE 2;
3,290,859 Patented Dec. 13, 1966 FIGURE 4 is a top View of a portion of the Ventilating system shown in FIGURE 1 taken in the direction of the arrow 4;
FIGURE 5 is a sectional View taken along the line 5 5 in FIGURE 4;
FIGURE 6 is a sectional View taken along the line 6 6 in FIGURE 5;
FIGURE 7 is a top View of an alternative embodiment of the apparatus shown in FIGURES 4-6; and
FIGURE 8 is a sectional View taken along the line 8 8 in FIGURE 7.
Referring now to FIGURE 1, a conventional internal combustion engine 10 comprising a crankcase 12 and an oil tller tube 14 is illustrated. The filler tube 14 is connected to the engine oil in the crankcase and a filler tube cap 16 is conventionally mounted on the end thereof in any of a variety of ways. The engine is further provided with conventional accessory components in the form of an intake manifold 18, carburetion means 20, and an air cleaner unit 22. The carburetion means 20 includes a combustion air induction passage 24 and a throttle valve 26. The air cleaner unit 22 includes an annular housing 28 which supports an annular filter unit 30. A cover 32, which is fastened to the housing 28 by conventional fastening means 3d, secures the filter unit on the housing. A tuning chamber 36 is provided by the housing 28 and communicates with the air induction passage 24 through an annular opening 37 spaced circumjacent thereto. The air cleaner illustrated is open to the atmosphere through 360 around the entire periphery of the annular filter unit 30. Air is drawn radially inwardly through the lter unit and downwardly through a central passage 38 into the air induction passage 24.
The aforedescribed engine and engine components are intended to be merely illustrative in many respects. It should therefore be particularly understood that the air cleaner unit described and the carburetion means shown may, in the broadest aspects of the present invention, take the form of any of the variety of designs currently in use. Although a 360 air cleaner having a tuning chamber has been described and produces a particular result in combination with the subject Ventilating system, an air cleaner of any design with or without a tuning chamber may also be adapted for use with the ventilation system of the present invention as hereinafter described.
The present invention is directed to a ventilation system which may take the form of an adapter kit having ventilating system components which may be readily associated with conventional internal combustion engine components to provide for crankcase ventilation on those vehicles which are used in areas requiring crankcase Ventilation. Accordingly, the present Ventilation system may be easily installed on existing internal combustion engines currently in use and is readily adaptable for varying Vehicle makes and varying engine designs thereof. The Ventilating system is, of course, equally well suited for factory installation on new cars if desired. In general, the Ventilation system components comprise a novel breather cap 16 which is adapted to be substituted for a conventional oil filler tube cap, lengths of flexible hose 50, 52, an adapter tube 54, and a combination condensate and tire trap 56.
The exible hose are provided with a plurality of external convolutions 58 which define V-shaped grooves 59 and are made from a material such as thick neoprene rubber which will withstand exposure to varying conditions of engine operation and to oil, gasoline, and blowby contamination. In the broadest aspect of the inventi-on, the illustrated hose design is not critical except insofar as the hose material need be sufliciently iiexible for installation and resistant to chemical reaction and deterioration. However, particularly advantageous results are obtained by the illustrated preferred hose construction in regard to the means of connecting the hose to the engine components as hereinafter described.
The length of hose 52 is adapted to be connected at one end to the adapter ytube 54. The adapter tube 54 may take any of a plurality of forms and may be designed to be secured within or to an existing engine passage which communicates with the crankcase or to be inserted through a specially prepared opening in the crankcase wall. The end of the adapter tube extending outwardly from the engine is `designed with an outside diameter which snugly receives the hose 52 in telescopic relationship. A conventional wire clamp 60 may be provided to secure the hose on the adapter tube. Oil separating means in the form of an oil removing deflector plate `62 having a plurality of small apertures is centrally mounted within the hose 52. The deector has a zig-zag configuration and is slightly oversize relative to the inside diameter of the hose for retention thereby. The deflector 62 is adapted to remove oil entrained in the blowby as it flows through the hose. The deiiector is preferably located at a bend in the hose. The bend is located at the highest position of the hose and is vertically positioned above the adapter tube 54 so that oil removed by the deflector will return to the crankcase. The section of the hose on the other side of the deilector is inclined downwardly and connected at its lower end to the combination condensate and re trap 56.
As shown in FIGURES 2 and 3, the trap 56 comprises a pair of mating shells 70, 72 which are secured to one another by overlapped flanges 74, 76 to dene a charnber 78, The chamber 78 has a bottle-shaped cross-sectional conguration including a lower portion of substantially `constant cross-sectional and an upper portion of Varying cross-section dened by inwardly tapering wall portions 80, 82. Connecting holes 84, 88 are provided in the tapered walls 80, 82 and have a diameter approximately equal to or slightly less than t-he outer diameter of the hose lengths at the bottom of the grooves 88 between adjacent convolutions 90, 92. Consequently, the ends of the hose maybe compressed and inserted through the holes until a convolution has been fully inserted into the chamber 78. When the hose is released after insertion, it springs back to its original shape to provide an eective fastening means and seal between the end of the hose and the circumjacent wall of the trap. A baffle plate 96 is provided between the openings 84, 86 to prevent direct passage of blowby from one opening to the other. The chamber 78 is filled with a copper mesh pad 100 beneath the baffle 96. The pad serves as a ire trap to prevent any ames or sparks from passing through the chamber 78 between the openings 84, 86. At the bottom of the trap an outlet opening 102 is formed in a side wall. A rubber flap valve 104 is secured to the trap by a projecting portion 106 which is received within a corresponding opening 108 provided in the trap wall above the opening 102. The lower end of the valve overlies the opening 102 to permit condensate collected in the chamber 78 to drain outwardly but prevent the passage of air inwardly.
The length of hose 50 is mounted in the hole 86 in a manner similar to that previously described for mounting the length of hose 52 in the hole 84. The hose 50 extends upwardly and is connected at its other end to the induction air passage means at some convenient point. The most convenient point is through a side wall of the air cleaner. In the illustrative air cleaner structure, the end of the hose is shown to be connected to the tuning chamber 36 through a hole 110 in the bottom wall of the cleaner housing. The hose may be connected in the hole 110 in a manner identical to that previously described in relation to the hose length 52 and the hole 84 in the tire trap. The hole 110 may be formed in the cleaner housing 28 at the time of installation of the Ventilating system in any conventional manner such as by a cutting or piercing operation. The particular location of the hole is not critical and the flexible hose 50 could also be connected in a side wall at 112 or through the cover at 114. However, particularly advantageous results are obtained insofar as the Iconnection of condensate is concerned by bringing the hose into the lowermost portion of the air cleaner so that condensate will readily drain back to the trap. With the hose connected to a bottom wall of the air cleaner condensate collecting in the tuning chamber will drain downwardly through the hose S0 and into the trap '70. In addition, condensate which collects on the walls of the hose 50 and the upwardly extending portion of the hose 52 will also drain into the trap. When the condensate in the trap reaches the level of the opening 102 the condensate will drain outwardly through the flap valve 104.
In order to establish a Ventilating ow of air through the crankcase, a special iiller tube cap 16 is provided for association with the filler tube 14 as part of the ventilating system. Referring now to FIGURES 4-6, the preferred form of liller cap comprises a cap member having a cover portion formed by a top wall 142 and an annular rim portion formed by a cylindrical side wall defining a generally cup-shaped cavity, a filler tube receiving bushing 132, filter means 134, air inlet passages 136, and flow control means in the form of a valve element 138. The top wall is provided with a plurality of radially extending depressions 144, 146, 148-, as shown in FIGURE 4, which terminate in a centrally depressed wall portion 150 extending substantially parallelly to the top wall. The depressions 144, 146, 148 are inwardly stepped by the provision of transversely bent axially extending outer side wall portions 152, 154, 156 which are connected by curved transversely bent axially extending inner side wall portions 158, 160, 162. These axially extending inner and outer side wall portions extend `axially substantially parallel to the annular rim portion. The bottom walls of the depressions 144, 146, 148 form abutment surfaces 166, as shown in FIGURE 5, for the valve member 138 and limit its upward movement.
A valve support element having a pair of radially spaced cylindrical walls 172, 174 connected by a transversely extending web portion 170 is mounted within the cover 130. The walls 172, 174 are dimensioned to abuttingly engage the inner surface of the wall 140 of the cover and the outer surface of side wall portions 152, 154, 156. A pair of radially spaced embossments or ribs 17 8, are provided in the web portion and extend outwardly upwardly therefrom in a direction opposite to the side i walls 172, 174. Outer ow passage means are defined in part by a plurality of air inlet .passages 136 provided by apertures circumferentially spaced around the central web portion between the ribs 178, 180 as shown in FIGURE 6. The inlet bushing 132 is adapted to be telescopically mounted relative to the inner wall 172 of the valve support member 170 and secured thereto by any conventional means such as welding, The inlet bushing 132 is further provided with a centrally located annular shoulder 181 which is adapted to abut the end of the filler tube 14 and locate the cap thereon. In order to secure the cap on the filler tube 14 fastening means in the form of a plate spring retainer 182 is secured to the bottom wall 150 by a rivet or the like. The particular design of the inlet bushing 132 and the spring means 18-2 may be varied as desired to accommodate varying types of filler tube structure. For example, some iiller tube caps are conventionally provided with bayonet type locking means. In order to accommodate a bayonet type lock or other means, the inlet bushing structure 132 may be changed to provide a corresponding lock portion without changing the basic cap structure. Thus, for engines embodying alternative iiller cap structure, the inlet bushing and fastening means can be varied so that an adapter kit for a particular make and model of an automobile would have suitable fastening means incorporated in the iiller cap structure.
The inlet bushing and valve support element 170 are mounted within the cover 130 and may be secured therein by a plurality of radially inwardly bent tabs 136 which are integrally formed in the lower end of the side wall of the cover. The valve element 133 comprises an annular plate which is supported in a valve cavity, defined by the outer side wall 1d@ of the cover, the inner side walls 152, d, 156, the bottom walls 166 of the depressions 144, 146, 148, and the central web 176 of the valve support element, on the annular ribs 178, 160. In this manner the valve element is movable upwardly off of the ribs 1755, 18) to permit atmospheric air to flow in through the inlet ports 136 and into the filler tube 14. Communication between the cover 130 and the filler tube 14 is provided by a plurality of axially extending inner ow passages 190, 192, 194 formed by the inner side walls 158, 160, 162 of the cover 130, and the inner side wall 172 of the valve support element 170. Outer ilow passage means are defined by the axially extending side wall portions 1M), 172, 174, 180. An annular iilter element 134 of polyurethane foam or the like may be pressed into the outer flow passage means cavity between the side walls 172, 174 to filter all imcoming air. The valve provides one way flow of filtered air from the atmosphere to the crankcase through the filler tube and prevents any reverse flow of blowby from the crankcase to the atmosphere.
An alternative embodiment of the filler cap is shown in FIGURES 7 and 8. The structure comprises a cover 206 having a cylindrical side wall 262 and a curvilinear central wall 264. An annular valve support element 206 having radially spaced cylindrical walls 208, 210 which are connected by a central web portion 212 is welded or otherwise secured to an inlet bushing 214, The valve support element 206 is provided with radially spaced upwardly extending ribs 216, 218, and a plurality of inlet passages 229 as hereinbefore described. The upper end of the inlet bushing is provided with a radially outwardly extending flange 222 to provide an abutment surface for an annular valve 224. Tab elements 226, 22S are inwardly bent from the central portion of the inlet bushing to provide locating stops for the filler tube 10.1 which is adapted to be telescopically received therewithin. Spring means 230 may be secured to the cover by a rivet 232 or the like to resiliently engage the inner surface of the ller tube and secure the breather cap thereon. ln order to limit upward movement of the valve 22d a plurality of inwardly extending nibs 234, 236, 23S are provided in the cover. The nibs are adapted to engage and space the valve from the upper wall of the cover in the `uppermost position of the valve. As hereinbefore described, a filtering element 239 of polyurethane or the like is frictionally inserted between the side walls 208, 216 of the support element 206. The entire unit is secured within the cover by a plurality of radially inwardly extending locking tabs 24M) and such other fastening means as may be necessary. The operation of the device is identical to that described in relation to the alternative ller cap structure.
In adaptation of the subject filtering system to conventional engine structures, the conventional filler cap is replaced by a filler cap incorporating a filtering element and valve means as hereinbefore described. A suitable adapter tube 54 is connected to the engine through a passage in communication with the engine crankcase. An inlet opening of appropriate size is formed in a side wall of the air cleaner means. The length of `hose 52 is secured to the adapter tube at one end and the central portion of the conduit containing the deflector 62 is fixedly located at a point spaced thereabove. The fire and condensate trap 56 is fixedly mounted in any suitable manner below the detiector 62 and below the air cleaner. The end of the hose 52 is connected to the trap by compression and insertion through the opening 84, The other hose element 5@ is connected in a similar manner to the opening 86 in the trap 56 at one end and to the air ind duction means through the opening 114i` formed therein at the other end.
Pressure differentials existing between the air induction means in the crankcase will create a ow of blowby from the crankcase through the hose 52, the fire and condensate trap 56, and the hose 50 to the portion of the air intake passage to which the hose 50 is connected. The blowby is thereby mixed with the incoming air for combustion and returned to the combustion chambers of the engine to be consumed therein. The components of the system may be secured on or adjacent to the engine by any suitable bracket or fastening means which provide the aforedescribed vertical spacing relationships. The
pressure `differential existing between the tuning chamber 36 and the crankcase cause flow of blowby from the crankcase and reduces the pressure therein. The reduced pressure in the crankcase will cause the valve means in the filler cap to open to permit filtered air to flow into the crankcase. As the blowby passes through the bafe 62, oil entrained therein will be removed and returned to the crankcase. Condensate forming in the hose and turning chamber 36 will be returned to the condensate trap. The copper mesh in the condensate trap provides a fire trap which :prevents spark-s or flames in the air induction passage means from reaching the crankcase.
Certain modifications in design and arrangement of the various parts `have been presented. Such modifications and other alternative arrangements which utilize the principles disclosed herein are intended to be included within the scope of the invention as defined by the appended claims.
What is claimed is:
1. A cap for use in a crankcase Ventilating system and for association with an air inlet tube, comprising: a cap member having a cover portion and an annular rim portion defining a generally cup-shaped cavity, a central portion of said cover portion being depressed into said cup-shaped cavity and defining therein a wall extending substantially parallelly to said cover portion and transversely to said annular rim portion, radially extending depressed portions formed in said cover portion and extending from said central portion to said annular rim portion at spaced circumferential locations and being depressed into said cup-shaped cavity a lesser distance than said central portion, said central portion being connected to said radially extending depressed portions by outer side wall portions extending substantially parallel to said annular rim portion, said central portion being connected to said cover portion by inner side wall portions extending inwardly toward said central portion away from said annular rim portion and being spaced radially inwardly beyond said outer side wall portions, a tube member connected to said cover portion about said outer side wall portion and extending outwardly from said cupshaped cavity away from said cover portion substantially parallel to said annular rim portion, a plurality of axially extending inner fiow passages defined by said tube member and said inner side wall portions and opening at one end in said cup-shaped cavity and terminating at :the other end of said tube member, outer flow passage means defined by said tube member and said annular rim portion and communicating at one end with said inner flow passages and terminating at the end of said annular rim portion, filter support means provided in said outer flow passage between said tube member and said annular rim and adapted to receive and support annular filter means for filtering air passing through said outer flow passage, tab means bent radially inwardly from the annular rim to hold the annular filter means in position, and one-way valve means associated with the annular iilter means to limit How of air through said inner fiow passages and said outer flow passage means to a single direction.
2. The invention as defined in claim 1 and wherein said one-way valve means comprises an annular sheet of material mounted circumjacent said outer side wall portions in a valve cavity further defined by said radially extending depressed portions of said cover portion and said annular rim portion and said filter support means.
3. The invention as defined in claim ll and wherein said filter support means comprises a channel-shaped annulus having parallel cylindrical side walls spaced and connected by an annular web portion, said side walls being connected to said tube member and said annular rim portion in said outer flow passage means and locating said channel-shaped annulus in an outwardly opening position, a plurality of rib means formed in said web portion, passage connecting means formed in said web portion adjacent said rib means, and said one-way valve means comprising an annular sheet of fiexible material adapted to be seated on said rib means to close said passage connecting means and to move away from said rib means to open said passage connecting means to permit one-way flow of air therethrough.
4. A cap for use in a crankcase Ventilating system and adapted for association with an air inlet tube, comprising: a cap member having a cover portion and an annular rim portion defining a cup-shaped cavity, inwardly depressed portions formed in said cover portion and extending into said cup-shaped cavity, a channel-shaped annulus having parallel inner and outer cylindrical side walls spaced and connected by an annular web portion, the outer cylindrical side Wall being connected to said annular rim portion within said cup-shaped cavity and locating said channel shaped annulus in an outwardly opening position, tube means connected to the inner cylindrical side wall and having one end portion located inwardly beyond said web portion in said cup-shaped cavity and having another end portion located outwardly from said cup-shaped cavity beyond the end of said annular rim portion, passage means formed between said tube means and said annular rim portion and through said web portion and extending in said Itube means, valve cavity forming means provided on the one end portion of said tube means to define a valve cavity in association with the inwardly depressed portion of said cover portion and the web portion of said channel-shaped annulus, and movable valve means mounted in said valve cavity for controlling flow through said passage means.
5. The invention as defined in claim 4 and having said movable valve means comprising one-way valve means mounted in said valve cavity and supported therein on said web portion for movement between passage opening and passage closing positions.
6. The invention as defined in claim 5 and wherein: said one-way valve means comprises an annular ring of sheet material mounted circumjacent said tube member, a plurality of rib means formed in said web portion and extending inwardly into said valve cavity, said passage means extending through said web portion adjacent said rib means, and said one-way valve means being adapted to be seated on said rib means in said closed position and to be moved away from said rib means in said open position.
7. The invention as defined in claim 6 and wherein: an annular ring of filter material is mounted in said channel-shaped annulus between the parallel inner and outer cylindrical side walls thereof, and fastening means provided to hold said annular ring of lter material therein.
8. A cap assembly for association with an air inlet tube or the like comprising a cap member having a cupshaped cavity defined by a cover portion and an annular side wall portion, a tube receiving sleeve mounted interiorly of said cap member, a radially extending flange member connecting said tube receiving sleeve and said annular side wall portion and dividing said cup-shaped cavity into a valve chamber and a filter chamber, said valve chamber and said filter chamber being circumferentially aligned and located outwardly circumjacent of said tube receiving sleeve, flow ports provided in said flange member and providing communication between said filter cavity and said valve cavity, one-way valve means mounted in said valve cavity for limiting flow through said flow ports to a direction from said filter chamber to said valve chamber, and air filter means mounted in and filling said filter chamber to filter all air passing through said flow ports.
9. The invention as defined in claim 8 and wherein spaced annular rib means are formed in said fiange and extend inwardly toward said valve cavity, said flow ports being located between said rib means, and said valve means being seated on said rib means for closing said fiow ports and being movable away from said rib means toward said valve chamber to allow fiow through said fiow ports.
llt). The invention as defined in claim 9 and wherein said valve means comprises an annular fiexible ring seated ou said rib means within said valve cavity, and said filter means comprises an annular filter ring secured within said lter chamber.
lll. The invention as defined in claim 8 and wherein said air filter means is replaceable, and said valve means being mounted between said filter means and said tube receiving sleeve.
12. The invention as defined in claim 3 and having mounting means freely supporting said valve means in said cap for movement of all parts of said valve means between an open position and a closed position relative to said flow ports.
13. The invention as defined in claim 8 and wherein said valve means is formed from fiat sheet material, all parts of said valve means being freely movable to a closed position to prevent reverse fiow through said fiow ports opposite to said directions.
14. A cap means for an air inlet tube or the like of a. crankcase Ventilating system comprising a cover having a cylindrical side wall and a top wall, portions of said top wall being axially depressed to form a plurality of valve seats, a valve support member having spaced cylindrical side walls connected by a central web portion, a plurality of air inlet passages being formed in said c/entral web portion, valve means movably mounted between said valve seats and said valve support member to control flow through said air inlet passages, a cylindrical tube receiving bushing centrally mounted in said cap means and adapted to telescopically receive said air inlet tube, said valve support member being mounted between said bushing and said cylindrical side wall of said cover, a filtering element mounted between said spaced cylindrical side walls of said valve support member and covering said air inlet passages whereby all air passing through air said inlet tube is filtered, and said valve means being mounted on said valve support member over said air inlet passages for movement from an air inlet passage closing position on top of said central web portion to an air inlet passage opening position above said central web portion whereby ingress of air is permitted and egress of blowby is prevented.
15. The invention as defined in claim 14 and wherein radially spaced upwardly extending cylindrical rib means are formed in said central web portion on radially opposite sides of said air inlet passage means to provide a seat for said valve means.
16. The invention as defined in claim 1S and wherein the depressed portions of said cover extend radially inwardly from said cylindrical side wall, said depressed portions terminating in transverse axially extending side walls, said side walls being connected by a depressed central portion being axially inwardly spaced a further distance than said portions of said top wall which are axially depressed to form the plurality of valve seats, the side wall portions between said transverse axially extending side Walls being radially inwardly curved to form a plurality of air outlet passages in association with said bushing to conduct incoming air through said cover to said air inlet tube.
17. A filler tube cap comprising a cover member formed by a tubular portion closed at one end and open at the other end, support means of tubular form having an outside diameter smaller than the inside diameter of said tubular portion of said cover member and opposite axially spaced open ends, said support means being mounted Within said cover member in spaced relationship to said tubular portion of said cover member with one open end of said support means located adjacent the closed end of said cover member, an air inlet passage ,between said support means and said cover member extending from the open other end of said cover member to the open end of said support means adjacent the closed end of said cover member, an air outlet passage extending through said support means from said open end of said support means adjacent the closed one end of said cover member to :the opposite open other end of said support means, transversely extending partition means extending between said tubular portion of said cover member and said support means and dividing said inlet air passage into a lter chamber adjacent the open other end of said cover member and a valve chamber adjacent the closed one end of said cover member, air port means in said transverse partition means connecting said lter chamber and said valve chamber, filter means mounted on one side of said transverse partition means in said ilter chamber, and one way valve means mounted on the other side of said transverse partition means in cooperable engagement with said transverse partition means adjacent said air port means and limiting air ow to a path extending from said open one end of said cover member through said filter means and said air port means past said valve means to the open end of said support means adjacent the closed other end of said cover mem ber and through said support means to the opposite open one end thereof.
References Cited by the Examiner UNITED STATES PATENTS Re. 25,562 4/1964 Konchan 220--44 1,286,930 12/1918 Bruckner 123--119 1,427,337 8/1922 Tracy 123-119 1,784,067 12/1930 Holtson 55-511 1,864,604 6/1932 Lemmerman 55-501 2,056,755 10/1936 Welch 220-44 2,113,447 4/1938 Hardings 123-119 2,114,240 4/1938 Sharrard 123-196 2,154,072 4/1939 Kamrath 55-504 2,244,403 6/1941 Root 123--119 2,496,883 2/1950 McKalip 55-495 X 2,532,888 12/1950 Brown 55--510 2,543,909 3/1951 Hatheway 285-238 2,726,732 12/1955 Faust et al. 55--219 2,742,057 4/1956 Krieck 123--119 2,760,596 8/1956 Kellie 55-219 2,836,258 5/1958 Price.
3,012,631 12/1961 Kaser 55-497 X 3,016,890 1/1962 Bibo 123-196 3,030,942 4/1962 Thompson 1231 19 3,071,285 1/1963 Friend. 3,146,194 8/ 1964 Hathaway 13H-*516.15 3,167,416 1/1965 Humbert et al. 55--505 FOREIGN PATENTS 716,222 9/ 1954 Great Britain. 751,289 6/ 1956 Great Britain.
HARRY B. THORNTON, Primary Examiner.
REUBEN FRIEDMAN, Examiner.
B. NOZICK, Assistant Examiner.