US2136098A - Air compressing apparatus - Google Patents

Description

Nov. 8, 1938.

L. H. BROWNE 2,136,098

AIR COMPRESSING APPARATUS 15 Sheets-Sheet 1 Filed July 28, 1957 INVENTOR L z'ndsay H Browne.

ATTORNEYS Nov. 8 31938,

L. H. BROWNE AIR COMPRESSING APPARATUS Filed. July 28, 1957 5 ma ma 5 Sheets-Sheet 2 'INVENTQR Y Llkwisa fi fmsgma.

Nov. 8, 1938. I. BROWNE AIR COMPRESSING APPARATUS Filed July 28, 1937 3 Sheets-Sheet 3 m N m U A INVENTOR Lindsayliflrowne.

Patented Nov. 8, 1938 2,136,098 AIR COMPRESSING APPARATUS Lindsay H. Browne, Pittsiord, Y., assignor to Kellogg Compressor and Manufacturing Corporation, a corporation of New York Application July 28, 1937, Serial No. 156,075

'1' Claims. (Cl. 230-58) This invention relates to improvements in air Figure 16 is a detail view of the valve plate;

UNITED STATES PATENT, OFFICE compressing apparatus. and

An object of the invention is to provide an Figure 17 isavertical fragmental sectional view improved air compression unit including comof the first stage suction and discharge valve pressor, motor, storage tank and accessories. structures and mounting taken on the line i1-l1, 5

Another object is to provide a unit of the Figure 12. above nature which is quiet and smooth and Referring to Figure 1, the numeral 20 indiefficient in operation. cates a storage tank provided with feet 2| and A further object is to provide a unit of the pressure gage 22. Brackets 23 welded to the tank above type in which the motor and compressor 20 have secured thereto resilient mounting pads 10 are supported on the tank by vibration absorbing 24, preferably of the structure shown in detail means eliminating all metallic connections bein Fi ures 3 and 4- tween the elements. Referring to the latter figures, the pad 24 Still another purpose is to provide improved consists of a cupped metallic mounting plate 25,

discharge means for delivering the compressed a rubber body 26 secured into and extending 15 air into the storage tank by which noise due to above the plate 25, and a central bolting cup 21 drumming or pulsation of the discharge is elimiof metal secured in the body 26 and resiliently nated, and by which any leakage from the valve separated thereby from the mounting plate. The outside the tank is rendered impossible. plate 25 and cup 21 are preferably made of Another purpose is the provision of a unit instampings provided with tongues 28 and 29 em 20 cluding a compound compressor having improved bedded in the rubber body 26, the entire assembly head and valve structure, and in which the being permanently Vulcanized together- The crankcase is sealed from the outer air. mounting plate has lugs 30 provided with A still further object is to provide improved holes 3| through which t e D is bolted to the 25 means to cool the air between stages and before brackets 23, Figure 1, and'central holes 32 in 25 delivery to the storage tank. g the bolting cups 21 accommodate bolts 33, Figure Other objects and advantages of the invention 1, by means of which a frame or base 34 is secured will become evident during the course of the folto the pads.

lowing description in connection with the ac- From the foregoin it W be e at t e 30 companying drawings, in whichbase 34 and tank 20, while firmly connected, are 30 Figure 1 is a perspective view of a preferred resiliently insulated from each other by the form of the invention; pads 24.

Figure 2 is an exterior detail view of the u d on t s 3 is a mp ss 35. resilient discharge connecting device; preferably of the oe pe, nd a Suitable 35 Figure 3 is a plan view of a preferred form driving motor 36. The compressor 35 has atriple 35 of resilient mounting device; grooved flywheel 31 acting as a pulley and driven Figure 4 is a vertical sectional view of the, throu h thr s 8 from th motor pu l y same; 39. The spokes 40 of the flywheel 31 are formed Figure 5 is a longitudinal sectional view of one s fen-vanes, Which When in motion p v de a 40 form of the discharge check valve; blast of cooling air as hereinafter set forth. 40

Figure 6 is an end elevation of the same; T Compressor 35 is q pp d w h a ead Figure 7 is a side elevation of the same; Ofa yp Shown in detail in Figures 13 nd. Figure 8 is a longitudinal sectional view of an the head being belted t0 the cylinder ock alternative form of discharge check valve; Figure The block 42 has e low Pressure 01 rst 5 Figure 9 is an end elevation of the ame; stage cylinder 43 and a high pressure cylinder Figure 10 is a detail view of the discharge check the lines 011 Which the inner u e ences valve disc shown in Figure 8; of these cylinders register with the headv 4i Figure 11 is a detail view of the spring tai r being indicated by dotted and dashed lines 45 and for the same; 46 respectively on the bottom view of the head, 50 Figure 12 is a horizontal sectional view of the Figure 50 cylinder head; A suction or inlet elbow 41, Figures 12 and 13, Figure 13 is a bottom view of the same; preferably integral with the head 4|, leads into Figure 14 is a detail view of the valve seat ring; an inlet pocket 48. Two valves 49 and 50, con- Figure 15 is a similar view of the valve restructed in a manner hereinafter described, pertainer ring; mit the passage of air from the pocket 48 to the 55 first stage cylinder 4i. A second pair of valves 5| and 52 permit discharge of air from the cylinder 4| to a second pocket 53, from which a connector elbow 54, Figures 1 and 12, conducts the air to a finned tube 55. The tube 55 is formed in a loop disposed in position to receive a blast of cooling air from the fan-blade spokes 40 0f the flywheel 31, and leads through a second elbow fitting 56, Figure 12, into the inlet pocket 51 of the second or high pressure stage of the compressor. The finned tube 55, so disposed as to receive the cooling blast from the flywheel, this operates as an inter-cooler between stages of the compressor to dissipate heat of compression from the first stage.

From the pocket 51 a valve 58, of construction identical with that of valves 49 and 50, admits the air to the high pressure cylinder 44 from which after compression it is discharged through a valve 59 and pocket 68 to a discharge tube 6| hereinafter described.

All the valves noted above are of identical construction, consisting of parts shown in detail in Figures 14, 15, 16 and 17. These parts consist of a seat-ring 62, a guide cup 63, a valve plate 64 and a conical compression spring 65.

The seat-ring 62 has a flat annular seat portion 66 raised slightly above the outer rim of the ring and above a central depression 61, the seat portion 66 being pierced by a plurality of arcuate slots 68.

The guide cup 63 consists of a short cylindrical barrel 69 formed integrally with a flat perforated head or spider I0. Both the seat ring 62 and guide cup 63 are threaded on their peripheries.

The valve plate 64 is of thin resilient steel, and is hexagonal in shape in rounded corners H and a central hole 12.

Figure 17 shows in sectional detail the manner in which two identical sets of the above parts are disposed in the head 4| to form inlet valve assembly 49 and discharge valve assembly 5|.

Referring first to the inlet valve assembly 5|, Figure 17, it will be seen that the seat ring is screwed against a shoulder 18 at the upper end of a threaded hole 14 leading from the lower face of the head 4| to the pocket 48, the annular seat portion 66 being directed downwardly. The thin valve plate 64 is held against the seat 66 by the conical spring 65, covering the arcuate slots 68. The guide cup 68 is screwed into the threaded hole 14, the end of the cylindrical barrel 68 tightly engaging the rim of the seat-ring 62 and locking both parts in place. The rounded corners of the valve plate 64 fit loosely inside the barrel 6! which thus serves to guide the valve plate, the spider 10 serving to holdthe spring 65 in compression against the valve plate to urge the latter against its seat 66.

The end of the barrel 68 is bevelled at 15 and the shoulder 18 may be grooved or undercut at I6, thereby providing narrow circles of contact between the mating parts and permitting air-tight joints without the use of gaskets.

When by descent of the piston in the compressor cylinder 43 a partial vacuum is created therein below the head 4|, the preponderance of pressure in the inlet pocket 48 acts through the arcuate slots 68 to press the valve plate 64 downward from its seat 66 allowing air to pass through the spider 10 and into the cylinder. In its passage the air passes around the hexagonal periphery of the valve plate and also through the central hole 12, giving a relatively large area of inlet opening with very small motion of the valve plate. This fact,

together with the extreme lightness and resilience of the valve plate, results in very quiet valve action and low resistance to the passage of air, which advantages are further augmented by the use of the two identical inlet valve assemblies 48 and 50 to divide the total volume drawn into the compressor.

The discharge valve assembly 5| is identical with the inlet valve assembly 49 described above except that the entire assembly is inverted, the head or spider end of the cup 63 being screwed against the shoulder 13 and the seat ring 62 becoming the locking member. The operation of the valve is the same as described except, of course,

that it permits discharge of air from the first stage cylinder 43 to the inlet pocket 51 of the high pressure cylinder.

The inlet and outlet valves 58 and 59 of the second or high pressure stage are identical in structure with those described. Thus all valves are interchangeable, a condition highly advantageous both from the view-points of manufacture and service. The simple and compact standardized valve structure allows great flexibility in design of the compressor for different sizes and capacities, as the valves may be disposed singly or in multiple in any desired combination. To widen the field of capacities for which the compressors are designed, a second standardized valve assembly may be provided, identical in structure with that described above, but of smaller size, and in some cases assemblies of both sizes may be embodied in one compressor in order to achieve the most advantageous spacing, grouping and capacity of valves.

The discharge tube 6|, previously referred to, is composed of externally flnned tubing. It is formed in a loop encircling the shaft of the compressor in the zone of air blast from the flywheel fan spokes 40 as shown in Figure 1. The tube 6| thus constitutes an after-cooler giving up heat of compression to the flywheel air-blast in the same manner that the loop 55 operates as an intercooler.

The discharge tube 6| terminates in a union 11 to which is secured a length of resilient hose or tube 18, Figures 1 and 2, preferably of a reinforced synthetic rubber construction. The

. other end of the resilient section 18 is secured to a threaded connector 18 which is screwed tightly into the inlet end 80 of a check valve assembly 8| shown in detail in Figures 8, 9, 10 and 11.

Referring to Figure 8, it will be seen that the check valve unit 8| has a body 82 into which is threaded a cap 83 formed with a constricted central 'nozzle 84 and enclosing a cylindrical chamber 85. A resilient seat ring 86, of rubber or the like, is fitted into an annular recess in the body 82, a thin cylindrical inner wall 8'! of the latter extending substantially through the rubber ring so that the latter is rigidly supported against distortion,

on its inside as well as on its outside circumference. A valve disc 88 has a raised annular portion 88 engaging the seat ring midway between stop to limit the opening motion of the valve disc 88.

The body 82 is provided withan exterior tapered thread 85 which is screwed into a suitable fitting 86 in the top of the tank 20, Figure 1. Thus, the entire valve mechanism projects inside the tank 20, and there are no exterior joints in the check valve assembly through which leakage might occur to the outer air.

In operation, the chamber 85 and restricted nozzle 84, both located inside the tank 20, act as a a muffler for discharge of compressed air into the tank. Any pulsations of air through the valve are equalized in the chamber 50 so that the discharge of the air through the nozzle 84 occurs smoothly and at a practically constant rate. By this means drumming or audible vibration of the air discharge into the tank is eliminated. The motion of the. valve disc 88 takes place entirely between resilient limiting means, that is, between the rubber seat ring 86 and the stop spring 95, so that no clicking or hammering can arise at this point. The combination of this valve action and the elimination of pressure pulsations as described above results in a substantially silent air discharge into the tank 20.

The contact of the valve disc with the middle portion of the face of the rubber seat 86, and the latters rigid support, as previously set forth, resulting in long seat life and sustained tightness of the valve.

A tapped hole 81 in the valve body 82 near its inlet end is provided to permit connection by means of a small flexible tube 98, Figure 1, to a combined pressure switch and magnetic unloader 89 mounted on the base 34 behind the motor 36. The structures of such pressure switches and unloaders are well known to those skilled in the art and therefore are not described herein, their functions being to break the motor circuit when the pressure in the discharge line rises to a predetermined point and at the same time to exhaust the discharge line to the atmosphere through the tube 98, so that restarting of g the compressor occurs only against atmospheric pressure.

With small compressors an alternative form of check valve unit shown in Figures 5 and 6 may be used, in which the body I00 is constructed at IOI for a tubing union connection. The cap I02 encloses the equalizing chamber I03 in which is guided a light disc valve I04 and its compression spring I05. The cap I02 has an exterior annular stepped groove I00 from which a hole I01 leads into the chamber I05. A resilient metal clip I08 is sprung into the outer step of the groove I06, leaving a slotted opening I08 disposed circumferentially opposite to the hole I01.

In operation, the alternative valve unit functions .in substantially the same manner as pre-- Some of the air from the viously described. equalizing chamber I03 escapes directly through a small hole IIO, but the major portion is forced to pass out the hole I01, thence around the annular passage formed by the groove I05, and finally out at the slot I08. By the restriction and labyrinthine passage of the air from chamber I03, pulsations and drumming are eliminated as previously set forth.

The crank case III of the compressor 35, Figure 1, is not provided with the usual atmospheric breather, but instead a pipe II2 leads from the crank case to a tapped boss H3 in the inlet elbow 41. A combined inlet muiller and air filter II4, secured to the end of elbow 41, silences and filters all inlet air drawn into the compressor. The connection of the pipe II2 as described allows the crank case to be sealed from the outer air, all breathing taking place with filtered air from the muiiied inlet passage. Contamination of the crank case lubricant with dust and dirt is thereby avoided, and the panting sound common to open breathers is entirely eliminated.

From the foregoing description it will be seen that the cooperation of the features of the invention set forth throughout cooperate to produce a silent and eflicient compressing unit.

Pneumatic noises are eliminated by the inlet muflier, internal breather, light and efficient compressor valves, and the combined check valve and discharge muffler structure, while the resilient connection of the compressing mechanism to the tank 20 by means of the pads 24 and the flexible discharge coupling 18 prevents transmission of any mechanical or electrical vibrations to the tank and its foundation.

The location of the finned inter-cooler 55 and after-cooler 6| in the air-blast of the flywheel 31 contribute to the quietness of the machine by eliminating auxiliary fans, and the shape and large cooling surface of these members exposed to the air blast, in cooperation with extensive cooling fins II5 on the cylinder head 4I, provide thorough dissipation of the heat of compression prior to delivery of air to the storage tank 20.

While the invention has been described in preferred form, it is not limited to the precise structures set forth, as various modifications may be made without departing from the scope of the appended claims.

What is claimed is: I

1. In an air compression device, in combination, a storage tank, a plurality of resilient pads secured to said tank, a compressor base mounted on said pads and secured thereto, a compressor on said base, a motor on said base and connected to said compressor to drive the same, a discharge line on said compressor, a discharge check valve within said tank, means including a resilient tubular coupling joining said discharge line to said check valve, and control means including means to release the pressure from said discharge. line and resilient coupling.

2. The combination claimed in claim 1 wherein said control means includes means on said base and responsive to pneumatic pressure to control the operation of said motor and compressor, and a resilient tube adapted to transmit discharge pressure from the inlet side of said check valve to said control means.

3. In a device of the character described, in combination, a storage tank, a compressor resiliently mounted thereon, a discharge line on said compressor, a check valve in said storage tank, a resilient coupling connecting said discharge line to said check valve, and resiliently connected means to unload pressure from said air compressor having a. discharge line and means to unload pressure from the same, a storage tank, and a check valve unit connected to said line and secured to said tank in sealing relation, said unit comprising an elongated body projecting into said tank, a check valve in said body within said tank, and means in said tank to retain said valve in said body.

6. In a device of the character described, a. discharge check valve unit comprising a body having an inlet passage therethrough, a closure cap on said body and forming therewith an enlarged expansion chamber at the inner end of said passage, said cap having a constricted outlet therethrough, a resilient seat ring in said body surrounding the entry of said passage to said cham" ber, a valve disk guided in said chamber, and a spring urging said disk against said seat ring, said cap having a circumferential groove with stepped sides and a hole connecting said groove with said chamber, and including a snap ring disposed in the outer step of said circumferential groove, said snap ring having a slot spaced circumferentially from said hole whereby an exit from said cham-' her is provided through said hole, around the inner step of said groove and through said slot.

'7. In an air compression device, in combination, a storage tank, a plurality of resilient pads secured to said tank, a compressor base mounted on said resilient pads, a compressor on said base, said compressor having an inlet pipe and a closed crank-case, means on said inlet pipe to silence the intake of air thereto, a breather tube connecting said crank-case to said inlet pipe between said silencing means and said compressor, a discharge line on said compressor, a check valve in said tank, means including a resilient coupling connecting said discharge line to said check valve, means to silence the discharge of air through said valve into said tank, and unloading means to release the pressure from said discharge line.

LINDSAY H. BROWNE.

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