US3703069A

US3703069A - Compressed air filter

Info

Publication number: US3703069A
Application number: US8117A
Authority: US
Inventors: Harry L Wheeler Jr
Original assignee: DK PNEUMATICS Inc
Current assignee: DK PNEUMATICS Inc
Priority date: 1970-01-21
Filing date: 1970-01-21
Publication date: 1972-11-21
Anticipated expiration: 1989-11-21

Abstract

The air filter, the air regulator and the air lubricator, one or more of which are used in compressed air lines, such as those driving power tools, each having its own housing which may be selectively connected to one or more of the other housings to provide either a vertical or horizontal arrangement with respect to the air line axis with or without the use of fitting connections. The filter includes the metallic head containing inlet and outlet ports, a plastic chamber or bowl and a foraminous device therein to remove entrained impurities from the air and a collector to separate water from the air stream. The regulator includes a metallic casting with a valve means of controlling air flow responding to the diaphragm. The lubricator includes the metallic head containing inlet and outlet ports, a plastic chamber or bowl defining a reservoir and means to discharge oil vapor into the outlet port at a prescribed rate. By selective fitting of the housings together, communication is established through the inlets and outlets already provided therein and means is provided for securing the selected filter, or regular or lubricator together. The respective housings interlock and nest together in different relationships to fit into existing spaces or to save space.

Description

[ 1 Nov. 21, 1972 United States Patent Wheeler, Jr.

[57] ABSTRACT The air filter, the air regulator and the air lubricator,

[54] COMPRESSED AIR FILTER one or more of which are used in compressed air lines, such as those driving power tools, each having its own housing which may be selectively connected to one or more of the other housings to provide either a vertical or horizontal arrangement with respect to the air line axis with or without the use of fitting connections. The a filter includes the metallic head containing inlet and outlet ports, a plastic chamber or bowl and .a foraminous device therein to remove entrained impurities from the air and-a collector to separate water from the air stream. The regulator includes a metallic casting with a valve means of controlling air flow responding to the diaphragm. The lubricator includes the metallic head containing inlet and outlet ports, a plastic chamber or bowl defining a reservoir and means to discharge oil vapor into the outlet port at a prescribed rate. By selective fitting of the housings together, communication is established through the inlets and outlets already provided therein and means is provided for securing the selected filter, or regular or lubricator together. The respective housings interlock and nest together in different relationships to fit into existing spaces or to save space.

s i 77 6 mm a mu n r 9 H04 BGB B l 55 0m5 0. lflZ 30 U fi .M 61M 5 4 m m m" 9 s u u m m M "n I J90 a u N133 S m we" 03 .J T u 1 5 ,0 D a t N u "In" k n M M N E m] m n Puoo .M p B m 1 0 w M m m mew n l 4 51 uh P ukflnru w 0 m 52 C m wsm s ww P In B w mmm L m a o cT Rew s... N4 mm.- Aw0osw mt" 6 2 R T y e 9 2 7 S 3 e s ew 1 r n n 4 .r .munuluaw m m .m&mm HPSM J 8 "n 4 E M a I u n wwwww h 3 I 0 e n [[5 N 6383]. m R mm m U m d m a. In v 1 P m mk wmwmw h F A .DP UIF 390,630, 1 1 11] 1 mm N 2 l 2 2 8 UMZ W. H U K BEE-D 3333 Primary Examiner-Bemard Nozick ma W eon W n e H R k .m U a 4 a n r m m J J l 1 H. be I!" H PATENTEHNUVZI m2 SHEET 5 BF 7 COMPRESSED AIR FILTER This is a division of application Ser. No. 734,664 filed 6/5/68 now U.S. Pat. No. 3,559,764 issued 2/2/71.

In the lubricator arrangement, the volume of the lubricator bowl, which may be plastic, metal or other suitable material, is used as an oil reservoir and means is provided to inject a spray of oil into the air stream as it passes through the housing. When the individual respective filter and regulator or the filter lubricator and regulator housings are in intimate, combined pressure-tight relationship with the bowls for lubricator and filter, the entire assembly becomes a combined housing.

BACKGROUND OF THE INVENTION 1. Field of the Invention The field of the invention may include the general categories of pressure regulators, lubricators, and filters and the sub-category of lubrication by air pressure although it should be understood that in the present device the air lubricator may be omitted in which event the general subject would be that of air filtering through a porous filter element and since the present device includes the versatility of one or more of the filter or lubricator or pressure regulator, the field will vary depending upon which components arebeing considered.

2. Description of the Prior Art Prior art devices customarily include separate elements for pressure regulation, filtering and lubricating such as the air filtering and moisture separating device shown in the patent to Semon No. 2,467,408 which might be combined with the device for lubricating fluid pressure operative means in Semon No. 2,571,770 by the use of various pipe fittings which involves some amount of assembly and consumes space and it might be preferred in a given situation to use a combined COMPRESSED AIR TREATMENT DEVICE of the sort similar to that shown in Walters Pat. No. 2,459,398 wherein a single housing combines a filter device with a lubricating device thereby avoiding the separate housings and fittings mentioned previously. A similar arrangement to the combined type shown in Walters is found in Earle Pat. No. 2,730,269 which relates everything having to do with the filtering, the pressure regulation and the lubrication, to one single integral casing which is provided with the inlets and outlets therein but which requires that the various inlets and outlets not to be used must be deactivated and the stream directed accordingly. In the Earle device the internal construction of the single casing is important to the overall functioning and association of all the different elements and necessarily this requires some amount of manufacture and fabrication and care in the provision of the various communicating passageways and the deactivation thereof for selective use of only one or two of the three different elements. The Earle device does not lend itself to the sale to a customer who might use only the lubricator or only the regulator due to the internal construction of the casing. On the other hand, the instant invention is a very worthwhile compromise between the putting together by fittings or the like of the three different elements, or being restricted to two elements in one common housing or having to purchase a base unit casing which accommodates all three. At the same time each element of Applicants SUMMARY OF THE INVENTION A filter, regulator or lubricator component selectively combined for compressed air lines comprising three separate housings or bases selectively combinable by interlocking without external connections as two or three elements. Also, adapter means may be used to change the relative position of the components. Two elements arranged without adapters may be disassembled and recombined in a different relative position with a third element. In any arrangement when the elements are in pressure relationship there is a compact package without external fittings.

The lubricator of the present device provides a means for proportioning the oil that is discharged into the air stream to match the volume of the air flowing through the lubricator. In one form this is accomplished by means of a suction tube and valve one end of which projects into an outlet port and the other end of the suction tube projects into the oil reservoir in an air space above the surface of the oil. Also, the lubricator may be filled while the pneumatic system in which it is installed is fully pressurized and operating. This is accomplished by means of a valve arrangement acting in response to applied pressure differential.

In addition to the special relationship of the three elements for selective attachment directly to each other the elements may also be put together with pipe nipples and fittings in one of several different relations lps.

BRIEF DESCRIPTION OF THE DRAWINGS Other and further objects and advantages of my invention will be apparent upon reading the following specification taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of an assembled arrangement of filter, regulator and lubricator elements in vertical arrangement.

FIG. 2 is a disassembled assembly view showing the elements in FIG. I disassembled and in the process of being reassembled with bowls of the two elements sideby-side instead of opposite sides as shown in FIG. 1.

FIG. 3 is a cross-sectional view taken substantially along lines 3-3 in FIG. 1.

FIG. 4 is a cross-sectional view taken substantially along lines 4-4 in FIG. 1.

FIG. 5 is a perspective view of a filter-lubricator combination in a row in series.

FIG. 6 is a perspective view of a filter-lubricator arrangement side-by-side.

FIG. 7 is a perspective view of a filter-lubricator arrangement on opposite sides.

FIG. 8 is a perspective view of one of the elements used by itself with an adapter.

' FIG. 9 is a perspective view of the element in FIG. 8 without the adapter.

FIG. 10 is the element in FIG. 9 with the pipe elbow turned for attachment in a different manner.

FIG. 11 is a perspective view of a modified pipe fitting.

FIG. 12 is a perspective view of the elements in FIGS. 8 and 9 with a T fitting.

FIG. 13 is a perspective view of the pressure regulator used by itself in the airline.

FIG. 14 is a perspective view of a filter-regulator assembly using a capped lubricator base to obtain colinear inlet and outlet ports.

FIG. 15 is a perspective view of a filter regulator assembly with the outlet at right angles to the inlet.

FIG. 16 is a perspective view of a lubricator-regula- FIG. 17 is a perspective view of a filter-regulatorlubricator, having one inlet and two outlets for lubricated and unlubricated air respectively.

FIG. 18 is a graphic representation of the function and action of the lubricator oil flow.

DESCRIPTION OF PREFERRED EMBODIMENT With reference to FIG. 1, one form of the present composite filter, pressure regulator and lubricator comprises a filter component designated generally by reference numeral 20 and including a die cast head or base 24 and a filter bowl 26 which is threaded into the base. Base 24 includes an offset portion 28 with a threaded opening 30 therein.

The pressure regulator designated generally by reference numeral 34 comprises a handle cover 36 and an internal regulating valve arrangement designated by reference numeral 38 which is mounted on a base or die cast head 40 sometimes referred to as the housing or casing.

The lubricator component is designated generally by reference numeral 50 and comprises a die cast head or base 52 with an offset portion 53 having an inlet therein and base 52 has threaded removably thereinto a bowl 54 having a nut-knob 56 threaded onto a sleeve 58 supported inside the bowl 54 on an assembly 60 assembled with base 52.

The

various components

20, 34, and 50 are attached together in another relationship shown in FIG. 2 wherein the adapters which are identical are designated generally by reference numeral 70 and are threedimensional castings, bases or housings each having a bore 72 therein with a female inlet 74 and a male outlet boss 76. Male boss members 78 on the pressure regulator 34 match with and are inserted into the respective female inlets 74 in the adapters 70. The central openings in the bases of the filter 20 and the lubricator 50 lead through their

respective bases

24, 52 internally in said

bases

24, 52 through

outlets

80, 82 which are inserted onto the male outlets 76 on the adapters 70. Each adapter 70 has an end portion at the bore 72 provided with opposed notches 84 which are part of an assembly retaining means comprising a top plate 86 with projecting edges 88 that fit in the notches in the adapter 70 on opposite sides of the pressure regulator 34 and a plate 90 on the other side is positioned with projections 92 fitting into the slots 84 and plate 90 is secured to plate 86 by means of four screws 94 and nuts 96. In the FIG. 2 assembly, the

respective bowls

26, 54 are arranged side-by-side rather than one on top of the other as shown in FIG. 3. This allows some amount of versatility in the installation of the device depending upon the space and other factors.

FILTER 20 The-details of filter 20 comprises a base 24 previously mentioned having the inlets 30 and the outlets and the bowl 26 which is threaded into the cylindrical portion of the base 24. A foraminous filter element 108 is supported on a central post 104 nonseparably attached to filter bowl 26. The upper end of element 108 bears against a washer 125. The lower end is centered and sealed by disc 106, and is held in position by a compressure force applied thru the post 104 as the bowl 26 is screwed into head 28. A passage 110 on post 104 and a valve member 1 14 provide means for emptying accumulated fluid and contamination from the bottom of bowl 26. A flange 102 on post 104 supports two

porous collectors

100 and 101. The space below the element 100 is sometimes referred to as a sump and is used to contain collected contaminent which is mostly water. The pressure envelope formed by the bowl 26 and the base 24 is sometimes referred to as a filter housing. A deflector is mounted in the passageway from the opening 30 in the base 24 and the incoming air strikes the deflector 120 which turns the incoming air downward and imparts a strong whirling motion. This transition should take place very smoothly since the creation of turbulance tends to shatter the water droplets being carried with the air. Centrifugal action forces the suspended or entrained water droplets out against the wall of the filter bowl 26 and the spiraling air moves downward carrying the water with it until the nonabsorbent, porous, foraminous filter element 100 disperses the water and contaminents therein immediately and transmits it to the sump 122 where it is collected for removal through the drain 114. The air returns upward thru the center of the downward moving vortex and passes out of the filter assembly through the filter element 108. The collector 100 replaces the conventional device which in one form is a conically shaped baffle in the same general location. The purpose of the collector 100 is to help create a quiet zone in the sump 122 where the water may accumulate since it has been found that some of the baffles used in this place tend to shatter large water droplets at high rates of air flow resulting in the formation of smaller droplets which are carried upward in the air stream through the filter element and on into the pneumatic system which is undesirable. The porus collector 100 acts to some extent as a gas-liquid separator and the porous structure should be characterized by a high degree of interconnection, a very low resistance to the percolation of water therethrough and a substantial resistance to the passage of gas as a result of tortuosity and the resistance to wetting. The collector 100 is preferably nonabsorbent to some degree. While natural sponges meet some of the requirements sponges tend to wet easily and thus tend to retain water and resist percolat'ion whereas synthetic nylon sponges reduce interconnection but wet easily. Polymer foams such as styrene are totally lacking in inter-connection and therefore are impermeable but urethane ester foams of proper pore size are well suited because the urethane surface resists wetting. The pores must be large enough to permit the free passage of water and water-oil emulsions that characterize pneumatic systems. According to the previous described arrangement, the collector 100 is' relatively impermeable to air and therefore any water once collected in the sump 122 almost cannot be scavenged back into the system by sudden increases or surgings in an air flow as in the case when a solid conical baffle is used. Furthermore, the use of the collector 100 has another advantage in that there is a good deal of scale and rust carried with the air and when this material strikes the diaphragm 100 the majority of it will tend to embed itself in the porous structure thereof. If a conventional conical baffle were used, there is a good chance that most of the contamination would be carried upward and would accumulate on the outside of the filter element and after a period of time this would block the filter element and prevent the passage of further air flow. Such plugging effect necessitates frequent recleaning of filters in the air line service whereas the present arrangement should extend the life of the filter element substantially and provide also a definite economic advantage. The diaphragm 100 is a more efficient method of water removal and less water will get into the pneumatic system to be carried to the air tools and cylinders and therefore the life of the device that is using the air should be extended sufficiently to create an economic advantage. A still further advantage of the collector 100 is that if the amount of moisture in the air is small, that absorbed by the diaphragm during periods of high humidity will reevaporate during periods of low humidity thus saving maintenance.

REGULATOR 34 The air enters the regulator 34 through the port 123 in the fitting 124 positioned in the base 24 inside the filter 108 and as seen in FIG. 4 as well as other figures the cylindrical housing 38 is covered by the handle cover 36 which is held in place by an internal screw 140 which engages a collar 142 inside the housing 38 and which is resting in one end of a coilspring 144 having the other end pressed against a disc 146 attached with a flexible diaphragm 148 having a diaphragm collar 150 in which there is a recess containing an O-ring 151 and there is a valve stem 152 which has a small piston 154 operating in a plenum chamber 156 defined inside of the base 40 and in which chamber 156 there is a closing spring 158. Shaft 152 operates across a plenum chamber 156 leading from the inlet 123 and shaft 152 carries a valve 162 seated in the end of the chamber 156. Air enters the regulator through the inlet 123 thru entrance 160 and into the chamber 156 and since there is no load on spring 144 and since the area of the valve 162 is smaller than the piston 154 the pressure in the plenum chamber 156 forces the valve 162 closed. This is called the differential closing force. A further closing force is provided by the smaller spring 158 in case the air pressure present in the chamber or passageway 156 is not sufficient to actuate the valve 162 against friction. If a load is applied to the spring 141 by rotation of the handle cover 36 to move the screw 140 against'the collar 142 then the valve 162 will be opened and air will then flow through the valve 162 as indicated by the arrows and into the outlet plenum 166. Pressure in the outlet plenum 166 is transmitted through a small eductor tube 168 and passes to the diaphragm chamber 169 which forces the diaphragm 148 to the right in FIG. 4 compressing spring 144 to the right and as the pressure continues to rise the spring 144 is compressed sufficiently to allow the valve 162 aided by the differential closing force to shut off the flow. If there is no leakage or demand for air then the valve 162 will remain closed.

If for any reason the pressure in the outlet plenum 166 increases above the pre-set valve pressure established by the main spring 144, the diaphragm 148 will move to the right in FIG. 4 against the spring 144 and away from the valve stem 152 and it will open the relief valve 170 thereby allowing the excess pressure to escape through a hole in the cover 38. If on the other hand it is desired to increase the pressure permitted by the regulator, then the rotation of the handle-cover 36 which is also a handle and the resulting further compression of the spring 144 as mentioned previously will force open the valve 162 allowing the air to again flow into the outlet plenum 166. If air is demanded, the pressure in the outlet plenum 156 will drop, the diaphragm 148 will have moved to the left in FIG. 4 and the valve 162 will open under the force of the spring 144. The valve 162 will stay open until the pressure in the diaphragm chamber 169 again is sufficient to force the spring 144 to the right in FIG. 4 and close the valve. The eductor tube 168 functions as follows: assume that the spring 144 has just been adjusted so that a certain air pressure is delivered to the system with no flow. Then when flow is initiated, the pressure in the chamber 169 will drop, valve 162 will open and the movement of the valve to the left in FIG. 4 will allow the spring 144 to lengthen and exert less force and therefore when equilibrium between the air pressure and the chamber 169 and the spring 144 is again established it will be at a lower level than was originally set. By placing the mouth of the eductor tube 168 in the area of low pressure at the exit passage 174 of the outlet plenum 166, then the pressure in the diaphragm chamber 169 is dropped below the level of the average pressure of the airin the outlet plenum 166 and will therefore reach equilibrium with spring 158 while the pressure in the outlet plenum 166 is still close to the noflow valve pressure. Accurate design and fabrication and positioning of the eductor tube 168 should result in an almost flat pressure-air flow relationship.

LUBRICATOR The lubricator 50 in connected to the regulator 34 by 4 means of an assembly nipple 200 and air flows through the nipple 200 and through the ports 202 and into the air chamber housing and out through the lubricator outlet port 206. Oil is stored in reservoir which is defined by the bowl 54, the lubricator base 52 and the air chamber housing 207. As the air passes thru the holes in assembly nipple 200 it picks up the oil which is discharged from pick up tube 218. The high velocity and the turbulence in this zone shatters the oil droplets which are leaving the end of the tube 128 and creates a fog or mist of oil. The static pressure of the incoming air stream is transmitted up a sleeve 214 to a pressurizing valve 212 inside of sleeve 214 which is controlled with an adjustment knob 216 threadedly engaging the sleeve 214 and passing thru a cylindrical opening 209 in the bowl 5 4. If the adjustment knob 216 is set to open the valve 212, then the pressure will force oil up through the oil pick-up tube 218. A small bleed hole 224 is provided at the top of the tube 218 to prevent siphoning when there is no air flow or when the valve 212 has been closed. The closing of the valve 212 equalizes the pressure in the oil reservoir and the pressure in the outlet port 206 so that there is no pressure differential to force oil through the tube 218. Since there is no obstruction in the lubricator air flow passage, air may pass though the lubricator in the reverse direction without difficulty. Therefore, the instant lubricator may be located at an air cylinder to provide direct lubrication instead of upstream of the control valve which is usually at some distance from the cylinder.

One of the problems which must be solved in all lubricators is that of proportioning the oil discharged into the air stream to match the volume of the air flowing through the lubricator. In the absence of modifying means, the pressure differential which forces oil thru oil pick-up tube 218 is a highly non-linear function of air pressure and air velocity that is strongly influenced by the geometry of the assembly nipple 200 and the position of the point of termination of oil pick-up tube 218. Test results indicate a relationship of the type: qKQ"q is the oil flow rate in ounces per hour, K, a constant of proportionality, Q, the air flow rate in cubic feet per minute and an exponent which varies from 1.4 to over 3 depending on the specific factors previously mentioned. Thus, as an example, if the air flow rate were doubled the oil flow would increase from two and one-half to as much or more than eight times. Furthermore with this set up there would be no way to establish a desired rate for the oil flow.

In order to solve these two problems the lubricator described herein is provided with a suction tube 222 which projects into general zone of the outlet port 206. The pressure at the end of this tube 222 is less than the pressure on the end of the oil pick-up tube 218. The upper end of tube222 projects into the oil reservoir and into the air space 230 above the surface of the oil. Suction tube 222 also contains a valve means 223 which is sensitive to the air flow rate passing out of air chamber 207. This valve 223 consists of a rubber covered flat plate 225, which bears against the end of tube 222 attached to a compression spring 227 by a small wire. A small orifice in the upper end of tube 222 limits the amount of air which is drawn there thru. At very low air flows the valve plate 225, which is larger than tube 222 seals off the end of suction tube 22. Pressure is generated in air space 230 by air entering the reservoir thru valve 212.

Oil will be forced thru pick-up tube 218. At low air flow the rate of oil flow is determined solely by the resistance of the oil feed system and the pressure in sleeve 214. As air flow increases the dynamic head of the air stream forces the plate 225 away from the end of tube 222. Thus, under moderate to high air flow conditions a portion of the air entering the reservoir thru valve 212 is drawn off thru tube 222 thus lowering the pressure available to force oil into the tube 218. The rate of oil flow can be controlled by varying the amount of air entering the reservoir from sleeve 214 by means of valve 212 which is actuated by knob 216. As the air velocity is increased the valve 223 opens further and at the same time the difference in pressure between

tubes

218 and 222 increases. However the opening of valve 223 action increases the rate of air removal and relatively retards the oil flow. If the valve 212 is closed, the

difference in pressure between

tubes

218 and 222 will force the oil in the tube 218 to back up and return to the reservoir through the bleed hole thus providing a positive shut-off. By properly locating the lower end of the tube 222 and by sizing the upper end to limit the amount of air which can be drawn away from the reservoir and by establishing proper valves for the tension of spring 227 and the size of valve plate 225, the pressure in the oil reservoir can be maintained over a limited air flow range at a level more or less directly proportional to the volume of the air going through the air chamber cover 207. That is, if the volume of the air is doubled the flow of oil will also approximately double. The function and action of the suction tube 222 and valve 223 are best described by reference to FIG. 18 which presents the analytical situation graphically. Log-Log Coordinates are used for convenience since slopes thereon represent exponential values. Curve (C) represents the desired situation where oil flow and air flow are directly proportional curve (A) represents the case where there is no suction tube and the oil flow is governed primarily by the air pressure in the reservoir. The slope of this curve is typical and the valve may vary widely. Curve (B) is typical of an open suction tube (no valve) but with limiting orifice in the upper end. Curve (D) is typical of that which can be achieved by introduction of valve means 223 into the suction tube while curved D can only approximate curve C and must be paralled to curves (A) and (B) at its lower and upper ends respectively it is close enough for all practical purposes. The slope of curve D can be varied by appropriate adjustment of the valve, spring and orifice.

In order to obtain some measure of the amount of oil which is being discharged into the pneumatic system a small flow meter 236 of the tapered tube type is provided at the intake end of the oil-pick-up tube 218. The float in the oil flow meter 236 is a small ball 238 which, with the tapered tube, acts as a check valve to prevent reverse flow. It may be desirable under certain circumstances to provide additional one-way valves in tube 236.

To be commercially practical any lubricator should be capable of being tilled while the pneumatic system in which it is installed is fully pressurized and operating. This is accomplished in the instant system in the following manner: unscrew the adjustment knobs 216 several turns to totally close oil the pressurizing valve 212. Then unscrew the knob 216 another turn which further allows the pressure trapped in the lubricator to escape through a passage defined by the knob 216 and the end port 209. This pressure loss will create a pressure differential across the check valve ball 238 in the oil pickup tube 218 and valve 223 in the suction tube 222 and both valves will close. The lubricator reservoir is now fully isolated from the pressure system. The knob 216 may be removed and the reservoir is tilled and when the knob 216 which acts as a cap is replaced, the replacement opens the valve 212 and as soon as the pressure in the reservoir exceeds the pressure in the discharge outlet 206 the two valves will open and oil flow will be reestablished. The same relationship is true whether in the vertical one on top of the other arrangement in FIG. 3 or the side-by-side arrangement which is assembled in FIG. 2.

Sometimes the unit herein is referred to .as F-R-L (Filter, Regulator and Lubricator). The vertical assembly described above can be converted to a horizontal assembly as described above can be converted to a horizontal assembly as described below. Reference is first made to FIGS. 3 and 4. Adjustment knob 216, lubricator bowl 54 and filter bowl 26 along with element 108 and related components are removed form the assembly. Chase nipple 124 is unscrewed and removed along with washer 125. This releases the filter head 20 from the F-R-L assembly.

Assembly nipple 200 is now unscrewed and removed along with washer 229 with assembly 60. Lubricator 50 will now separate from the regulator body 40. The three functional sections of the F-R-L are now separate. Reassembly of the three components in the horizontal mode is made as follows: (Reference is made to FIG. 2). Seal rings 79 are pressed over regulator bosses 78. Adapters 70 are slid over bosses 78 and seated firmly against regulator body 40. Seal rings 79 seat against regulator body 40 and fit into a recess in adapter 70.

Lower and upper bridge plates 90 and 86 have two ridges 88, 92 the interior opposed faces of which slope out at an angle of 60 to the plate. These ridges are pressed into grooves 84 on the upper and lower faces of adapters 70. The side of these grooves closest to the regulator are also sloped at an angle of 60 to the plane of the adapter. Dimensional control is such that when clamp screws 94 which straddle regulator body 40 and adapters 70 are tightened, the two adapters 70 are wedged against the regulator body simultaneously compressing seals 79. This method of joining has proven capable of withstanding an internal pressure of 1000 psi without leakage or deformation.

Before reassembly, a tapped hole 250 approximately one-half inch in diameter is made in bases (head castings) 24 and 52. The center for those holes is already located in the castings.

To reassemble the filter slip seal ring 75 over adapter boss 76 and seal ring 77 into a groove 89 in a hole 91. Slide center port 82 of base 24 over boss 76. Line up hole 91 in adapter with threaded hole 250 in base 24. Reinstall washer 125 and chase nipple 124 in threaded hole in boss 76 and tighten. Please seal ring 79 over a plug bolt 254 and slip through hole 91 and thread into hole 250 and tighten. Guide filter element 108 already in bowl 26 over chase nipple 124 and screw bowl 26 into head.

Assembly of the lubricator is made in the same manner except that assembly nipple 200, washer 229 and modified air chamber assembly are used in place of chase nipple 24 and washer 125 to hold the head in place. A vented plug bolt 260 with vent 262 is used in place of a plug 264. Replace the bowl 54 and adjustment knob 216. This modified air chamber differs from air chamber 207 only in the configuration of

tubes

218 and 222. Tube 218 is shortened and hangs down into the bottom of the oil reservoir. Flow meter 236 is much shorter and only need project though air chamber housing 38 into the air space 230 above the oil. All action and control remains the same except for refilling.

To refill the inverted reservoir valve 212 is shut off by rotation of knob 216. Plug 260 which contains a vent bleed passage 262 is unscrewed several turns. This 10 permits the reservoir pressure, to bleed off past a seal 264. The plug is then removed and oil replaced in the reservoir through the passage thus opened.

It is believed that the method used to proportion the flow of oil from the lubricator is more effective than many systems currently in use.

An innovation in this F-R-L unit is the use of plastic port inserts 266. In F-R-Ls currently marketed the inlet and outlet ports are threaded for a specific pipe size i.e. V4, 56, A, etc. thus a distributor must carry a stock of each size. The external ports 206, 30 of the present filter and lubricator heads are tapped with three-fourths NPS thread which may be used with three-fourth inch pipe. If smaller pipe sizes are required, a series of moulded plastic inserts 266 are available. The present port inserts are not necessarily conventional pipe bushings. This difference is demonstrated in FIG. 3. These port inserts are completely inside of the three-fourth NPS female thread in the die cast head or

base

24, 52 of the filter 20, lubricator 50 or adapter 70. As the connecting pipe is screwed into tapered thread, the insert expands to seal against threads in head. Insert travel is limited by a shoulder. Overtorquing will strip the bushing, not the head. The connecting male thread, then, is in the same relationship to the filter or lubricator head as though there were no insert. With usual pipe bushing, the connecting line is frequently completely outside the ports and with sufficient vibration or torque, the bushing fails in the zone noted in FIG. 3. Use of these inserts insures a conformity between male and female threads, eliminates the need of pipe sealents, provides freedom from corrosion due to galvanic action and offers some degree of isolation from vibration. Deformation of the insert distributes stresses uniformly around the ports, thus reducing the probability of breaking the casting through pipe mislignment or over-torquing. These joints may be easily disassembled even after long periods of service without danger of stripping corrosion weakened threads. If the incoming pipe is inadvertently cross threaded, only the replaceable bushing, not the expensive head casting is damaged.

The elements of the instant F-R-L are unique in the variety of ways in which they may be combined. First, each of the basic element is a separate entity in itself. The filter, regulator and lubricator may be used independently of any of the other elements as shown in FIGS. 5 thru 13.

FIG. 8 depicts either a lubricator or regulator adapted for independent use. (the two units are externally similar except that the inlet and outlet ports are reversed.) An adapter 300 is mounted in precisely the same manner as adapter 70, FIG. 2. The sole distinction between adapters and 300 is that the latter has three-fourths NPS threads machined into the externally exposed port. The same function may be served by a modified standard 300 pound pipe I." 302 (Jigg). While it does not provide as attractive an appearance, the pipe "1. makes it possible to establish virtually any desired angular relationship between inlet and outlet ports. This freedom simplifies installation and alignment problems. Nor, is one confined to the horizontal plane. FIG. 12 shows a pipe T 304 used as thru inlet connection for a lubricator. Incoming air enters thru the horizontal leg of the T. Unlubricated air is taken off from the vertical leg to service (for example) a fluidic control circuit. The remainder of the air passes thru the lubricator and onto an actuating cylinder controlled, perhaps, by the fluidic circuit. The concept of bringing flow into and dividing flow off from a common connection, where that connection is an integral part of the F-R-L assembly is novel. Such a practice simplifies utilization and installation and, in addition represents a significant cost saving. Other custom designed manifolds or tie points can easily be made by any one familiar with pneumatics. A fill port 306 must be provided for refilling the oil reservoir.

A street L 308, a 45L" or virtually any other standard heavy duty fitting may also be used. FIG. depicts a street L filter inlet port connection oriented at right angles to the outlet.

The modification required to prepare a fitting for use as a port connection is shown in FIG. 11. A boss 310 identical in dimension with the boss 76 on adapter 70 is machined on one end of the fitting. The fitting need only be large enough in external dimension to provide a sealing surface for a seal ring 79. Three hundred pound to 3,000 pound fittings have been used. The thread connection at the machined and must be l inch NPT to match the regulator thread.

The regulator, FIG. 13, needs no port connection since one-half inch NPT threads are machined into the ports.

A frequently used combination of two elements of the F-R-L system is the filter-lubricator combination. This is commonly used where pressure regulation is not required, or is done on a system basis. FIG. 5 shows a co-joined filter 314 and lubricator 316. Each is a separate unit as described previously.

Units

314 and 316 are joined by a three-fourth inch NPT close nipple 212.

FIG. 6 shows the same two elements joined using two modified pipe Ls 302, and a short nipple 318. A distinct advantage of this combination is the freedom of orientation of the inlet and outlet ports. FIG. 6 shows both ports facing to the rear for front panel mounting.

The filter and lubricator elements may also be disposed vertically as shown in FIG. 7. A coupling or T 320 may be used as the co-joining member. This arrangement reduces installation space requirements.

Many applications require either filter and regulator or lubricator and regulator. FIG. 14 shows a filter-regulator combination. The assembly is the same as that shown in FIG. 1, except that

bowl

26 or 50 or 54 and the internal mechanism of the lubricator 50 have been replaced by a cap 322 which threads into the bowl recess in place of bowl 26. FIG. 6 simplifies this installation by eliminating parts and using the threaded outlet port of the regulator 34.

The position of the lubricator may be substituted for that of the filter in the foregoing examples, or used in its normal position as shown in FIG. 16. The regulator and either of the other two elements may also be joined by appropriate pipe connections.

Two arrangements of the complete F-R-L assembly have already been discussed (cf, FIGS. 1 and 2). The three elements may also be simply joined using pipe fittings in place of adapters 140. Such a method offers considerable freedom of port orientation. FIG. 7

L 350. Regulator and lubricator are joined by a nipple 322 and a T'324 in a manner similar to that shown in FIG. 6. Inlet and outlet ports are at right angles. It should be noted that unlike some presently marketed F-R-L units flow may be either left to rightor right to left.

While I have shown and described a preferred embodiment of the invention together with severalsuggested modifications thereof, this is by way of illustration only anddoes not constitute any sort of limitation on the scope of my invention since various alterations, changes, deviations, eliminations, substitutions, additions, variations and departures may be made in the fonns shown and described without departing from the scope of my invention as defined by interpretation of the appended Claims.

What is claimed:

1. A compressed air filter having a base on which there is connected a filter container, said base containing an inlet thereinto and an outlet therefrom, said inlet receiving a mixture of air, solid particles, oil and water droplets moved therethrough into said chamber, a deflector mounted in said inlet against which said incoming air strikes and is turned and moved downwardly by swirling into said container, a filter element supported inside said container covering the outlet to filter solid particles from the mixture passing therethrough from said inlet to said outlet, and a porous substantially non-wetting filter means supported across said container above a sump partly defined on one side by the filter means and said container, said filter means being below said filter element to distribute separated liquid from said mixture passing from said inlet, said filter means being characterized further by being substantially impermeable to gas flow but passing liquid therethrough to the sump.

2. The device in claim 1: said filter means being of a porous material providing a barrier interposed between the filter element and the inside of the container.

3. The device in claim 1: said filter means having pores arranged in a tortuous path having great resistance to air flow and diameter to exhibit negligible absorbency for liquids.

4. The device in claim 1, said container having walls defining three-dimensions, and said filter means being a three-dimensional material contacting the container walls at least partly to define the sump.

5. The device in claim 4: said three-dimensional material being traversed by a multiplicity of tortous interconnected pores.

6. The filter in claim 1: said filter means being of a porous soft, non-absorbent plastic foam material.

7. The filter means in claim 6: said filter having pores of a size large enough to pass water, oil and emulsions and length to provide substantial resistance to gas flow.