US2518869A - Muffler with rotatable baffle - Google Patents

Description

1950 T. K. CORLESS 2,518,869

MUFFLER WITH ROTATABLE BAFFLE Filed May 22, 1948 2 Sheets-Sheet 1 Inventor War/ 4; A. (aez'ss (lttornegs 2 Sheets-Sheet 2 T. K. CORLESS MUFFLER WITH ROTATABLE BAFFLE Aug. 15, 1950 Filed May 22, 1948 Patented Aug. 15, 1950 UNITED STATES PATENT OFFICE 2,518,869 MUFFLER WITH ROTATABLE BAFFLE Thomas K. 'Corless, Hempstead, N. Y.

Application May 22, 1948, Serial No. 28,589

13 Claims.

This invention relates to mufflers for mufiling the exhaust of internal combustion engines such as are used on automotive vehicles.

The principal obj ct of the invention is to pro vide a muffler having a rotor therein which is caused to rotate at a high rate of speed by the passage of the exhaust gases through the muffler, the construction being such that a suction effect may be produced which tends to decrease the back pressure in the engine, thereby promoting economy of operation, which silences the exhaust and which creates a turbulence promoting completecombustion, thereby eliminating or reducing smoke or odors in the gases discharged from the muffler.

Another object of theinvention consists in providing a highly durable muiiler construction which may be economicallyv manufactured, and in which the bearings for the rotary element of the muffler are so placed and constructed as to be maintained relatively cool, so that they may be maintained in effectively lubricated condition, and will provide a long period of usefulness without necessity for servicing.

Other objects and advantages of th invention will be apparent from the following description taken in connection with, the accompanying drawings which illustrate apreferred embodiment of the invention.

, The muffler of the present invention is an improvement upon that disclosed in my Patent No. 2,003,500, dated June 4, 1935. V

In the accompanying drawings,

Figure 1 is a plan View of a preferred form of muffler;

Figure 2 is a transverse vertical section on lines 2-2 of Figs. 1 and 4;

Figure 3 is a'similar section on line 33 of Fig. 1;

Figure 4 is a longitudinal section on line 4-4 of Fig. 1, the rotor being shown partly in elevation and partly in section;

Figure 5 is a detailed elevation showing a part of the rotor axle with the helical blades thereon.

Referring to the drawings in detail, the mufiler construction illustrated includes a casing Ill, shown as cylindrical in form and provided with flanges H. to which are bolted end plates I4. In

the top of the casing is an inlet opening I6 over which is secured the inlet fitting IS. The latter may be secured to the top of the casing in any suitable manner, as for. example by welding. The outer end of the inlet fitting is flanged as indicated at 28, and to this is bolted th pipe 22 coming from the exhaust manifold of the engine.

The inlet fitting I8 is preferably made large enough to handle the exhaust from the maximum sized engine with which the muffler may be used. The same mufller with a slight change, to be described, may be used for engines of much smaller power than such maximum. In order to accomplish this result the opening i5 is preferably made somewhat shorter than the length of the intake fitting which is welded over it. This provides a baffle wall 24 cutting down the size of the inlet opening I6. In designing the muffler for a particular size engine, this baflle wall will be more or less extended, or cut away, and the size of, the opening I 6 more or less enlarged or reduced to fit the muffler to the particular case. When the muffler is fitted to an engine smaller than-its maximum capacity, the opening it is cut down sufficiently so that the exhaust gases will still enter the muffler at a sufliciently high velocity to secure proper operation.

Extended eccentrically through the casing is a .shaft 38 which is mounted to rotate in end bearings 32. Self aligning type ball bearings are preferably used to reduce friction. Where higher exhaust temperature is encountered, particularly in Diesel operation, distortion of machine parts from expansion stresses will be compensated for by these self aligning ball bearings. Bearings 32 are preferably mounted in housings 34 carried on struts 35 projecting from end walls 42. The bearings are thus spaced a considerable clistance from the casing so that they do not become overheated, this result being enhanced by the fact that air may circulate freely around the bearings and between the struts 35.

Mounted on the shaft 3i] is a rotor 38 which comprises a pair of end plates 40 provided with keys 4| securing the end plates 4!,- directly to the shaft 30. The end plates have holes 4 2 formed therethrough and carry a plurality of buckets 44. The buckets 44 are concave-convex, being preferably of approximately semi-cylindrical form having concave faces 45 in which the gases are received and which reverse the direction of flow, thereby producing a reaction against the buckets which causes the rotor to rotate rapidly in a clockwise direction, as indicated by the arrow in Fig. 2. Each bucket also carries an extension or baffle plate 48 on its back, such bafile plate extending substantially tangentially to the outer part of the back of the bucket, and sloping inwardly so that the terminal edge of the baffle is substantially opposite to the center of con cavity of the adjacent bucket. The gases in their reversal of flow in any particular bucket thus have to pass around the bafile projecting from the back of the adjacent bucket. The fact that the bafiles 48 are substantially tangential to the outer parts of the buckets near the leading edges 50 thereof, is important as it produces a form of bucket and bafile which is impinged upon by the gases entering through the inlet opening [6 such that a stream line effect is produced, causing the gases to be directed over the outside of the bucket adjacent to the leading edge and over the outside of the b'aflleplate lgiinto the adjacent bucket so that at this point a smooth flow of gases into the bucket is obtained. It has been found that this construction results in a substantially silent action, as there is no siren efiectproducedby the rapidly moving buckets, such as-has been found to occur when this formation at the outside of the bucket is not employed. Furthermore-the gases are directed in an eflicient manner, so. that high speed of rotation of the rotor is secured; jIhe buckets and end plates may be joined in any suitable manner. As-indicated the end: plates are provided with recesses'fi9 shaped to fitthe ends ,of ,thebucketsyand the two end plates are held together "tightly against the -ends'-'of' the bucketsby bolts i. "Thegasestraveling around through the rotor are discharged '-centrifugally into the chamber 52 outsideof the *rotorwhich is of "maximum Width substantially opposite" to the, inlet opening. Part *ofthe gases" a'lso pass out throughthe' holes 42 in the end-plates l 0. Thebreaking up of-the gases 'and*this-"discharge endwise-of the rotor'-'is iurthermore" facilitated b the" useof helical bladesl'vdfornred-on a'sleeve "58 mounted on the shaft-"30f and connected to rotate-therewith,--as I by-meansiof a" pin 60. T-he'blades are-double right and left hand *hclices-,;- each-pair-meeting at its apex" 5! whichis'on the common-center line "of therotor; see Fig; 5. The outer "ends "of the helical blades preferably eXtendslightly-beyond 'the-end's ofthesleeve -58 a indicated at 62 andoverlie' inner hub portions 64 projecting from the insidesurfaces o-f'theend p'lates 4B.

"-Mountedin thecasing l9 at-each side of the rotorar'e stationary diffuser plates 10 havinga multiplicity of holes E2 therethrough3-- These diifuser plates separate the rotor chamber f-rom the-expansion chambers M which are between the diffuserplatesflll and the end walls M of the casing? The gasesfi after passing through the rotor whic'h: thoroughly mixes a'nd churns up such gases} pass through the holes It-intothe expansion chambers-la andleave the mufiler through discharge openings 16; which may-,if desired, be connected to a common discharge header 'la and to tail pipe-8B. lhe plates 'Hl may be "mounted in any suitable manner; but in order to avoidexpansion"stresses; are preferably not connected directly to the casing 'l0,-'-but are mounted 'at their centers on flanges which are mounted on sleeves 84 fittedin'sockets- 86 in the end'plates! 4; The inner diameters 'ofthe sleeves are such as topermit the shaft30 to pass freely through the same without frictioh'fbut clearance i 's 'keptassmallas"possible and owing to th'e long length of the sleeves 84 practically no leakageofthe' gases will "take place-between the shaft and the sleeves Leakage-is further-reduced by providing external hub fianges'td on-theout'er surface'sof the walls 48, these flanges" surroundingithe projecting inner ends 92*of the sleeves 84.

A nar-row clearance-isprovided between thesurfaces 'of'-9 l and 92 so as to obstruct'thefiow of as-but notto create friction. In. fdfil" to' dire the gases out from the spaces between the parts 99 and 92 fan blades 94 may be formed on the outer surfaces of the flanges 90.

The construction of the parts is such that many parts may be formed by welding together standard shapes. For example, the casing l0 may be a large section of pipe to which the flanges l2 are secured by welding, the buckets 38 may be formed by welding flat plates forming the baflies lB to curved halt-pipeesections constituting thebukets; the inlet 'fitting anaiyi-rbeiwelded to the casing, as already described; and the fittings around the outlet openings 16 may be similarly applied if desired. The end plates [4 and struts 36 are show-n 'as castings, but obviously may be otherwise fabricated if desired.

The bearings 34, being carried on the ends of struts 3iiat =akcorisiderable distance from the ends ofrthe easing, are easily maintained at a temperature below that which would interfere with proper lubrication. They are conveniently protected" from dustj' etcfcoming from tli'e ekhaust, by meanspf flanged collars "l flit-mounted on-the bearing casings? Fan bla'des l 04 =may*be--pro'- vided' on the coll arc these fail "blades-"being pitched" scias to drawcbol aii 'oyer 'the' bearings an'd'blo'w it 'towardstheends of the'muflierl'This keepsthe'dust'and a ny h'otexhaust'gases which may be "present away fror'n the' bearings? The bearings can be sufiiciently lubricated by pla c ing' 'ai suitable lubrieant in thebearingsi the oute endsof which are'clos'ed bycapsflil'r By providing a inufilertof the construction described with'a freely rotating rotor"therein;a high "efficiency of" operation of the 'engine"'is"se curedl At times when the. speed-of the .engine decreases"; or the throttle is closed,sri'thatxthe volume of exhaustgas decreasesj'the rapidly "revolving rotor; owningtoitymomentumywili apply a certain amount of suction to the engine exhaust" which freduc'e's back? pressure .andmakes for. most eflicientnoperation ,under' conditiondbf less than maximum -:power output. The action of the rotor in" th'oroughlyj'agitating a'n'dstirring up the gases,.fol1owed"by the" expansion of the gases 'inrthe casing'and through'thadifiuser plates 10 and into the expansion chamber'sJA tends to: promote complete' 'c'ombustion of'tlie gases, the substantial elimination of smoke Z'fro'm the discharge, and.reduction" or eliminatidnof noticeable odors fromi'the' 'ili's'charge'," particularly when" the mufller'is' used .with; a 'Diesetengine. Substantially silent operatidr'i is "also secured. The constructioh of'the rotor ahd its mounting isalso exceedingly durableand replacement or servicing of the parts is rarely required. l-

While'I' have illustratedand" described in detail one preferred form ofmyjinventionlit isto beunderstoodthatbhanges'may'be made therein and the invention embodied in'otherlstructures. I do 'nOtJtherefore, d'sir'elto "limit rhyslfto-the specific constructions illustrated; but :intendfito cover m invention broadly-in whatever form its principle mayl-beembodied. Z 'i J 1. A'mufiler for internal combustion engines, comprising a casing',..a rotor mountedin saidfcasing to rotate about .an axis eccentrically I'o'cated inthe casing, an'inletlpoiitopenin into the casing permitting 'thelexhaust gases, to .enter the casing substantially tangentially of 'the "rotor,v .a perforateddiifusion' plate mounted in the casing transverse to the axisliofirotatior'i lof the rotor dividing off aniexpansion chamber inthe casing fromtherotor chamber of the casing, anda gas discharge port opening into the expansion chamber.

2. A mufiler for internal combustion engines including a casing having a tangential inlet port and an outlet port therein, and a rotor mounted for rotation in the casing, said rotor having a plurality of concavo-convex buckets therein, said buckets having baliles extending substantially tangentially from the convex sides thereof near the outer edges of said convex sides.

3. A mufiler for internal combustion engines including a casing having a tangential inlet port and an outlet port therein, and a rotor mounted for rotation in the casin adjacent to said inlet port, said rotor having perforated end plates to provide gas discharge openings, and a plurality of concavo-convex buckets therein, said buckets having bailles extending substantially tangentially from the convex side thereof near the outer edges of said convex sides, said buckets being fixed between said end plates.

4. A muffler for internal combustion engines including a casing having a tangential inlet port and an outlet port therein, and a rotor mounted for rotation in the casing adjacent to said inlet port, said rotor having a plurality of concavoconvex buckets therein, said buckets having baffles extending substantially tangentially from the convex side thereof near the outer edges of said convex sides, said rotor being mounted for rotation about an axis eccentrically located in the casing nearer to the inlet opening in the easing than to the opposite side thereof.

5. A mufller for internal combustion engines comprising a casing, a pair of perforated diffusion plates mounted in the casing, and spaced from the ends thereof so as to divide the casing into a central chamber and two diffusion chambers, an inlet port opening into the central chamber, outlet ports opening into the diffusion chambers, and a rotor mounted to rotate in the central chamber adjacent to the inlet port, said rotor comprising end plates having large perforations therethrough for discharging gases into the spaces adjacent to said perforated diffusion plates, and concave buckets carried by and shrouded between said end plates.

6. A muffler for internal combustion engines, comprising a cylindrical chamber having end walls, bearings carried by the end walls mounted eccentrically with respect to the axis of the chamber, a shaft carried in said bearings and extending through the chamber, a pair of perforated diffusion plates carried by the end walls and spaced therefrom so as to provide diffusion chambers between said end walls and the respective diffusion plates, an inlet port opening into the chamber between the diffusion walls, an outlet port opening out of each diffusion chamber, and a rotor mounted on said shaft opposite to said inlet port, said rotor including a plurality of concave buckets adapted to receive exhaust gases entering the chamber through said inlet port, and end plates between which said buckets are enclosed, said end plates having large perforations therethrough for passage of the exhaust gases to the diffusion chambers.

'7. A muifler for internal combustion engines comprising a chamber, a perforated diffusion plate spaced from one end thereof, a rotor mounted in said chamber adjacent to said diffu sion plate for rotation about an axis at right angles to said plate, said rotor comprising end plates and buckets carried thereby, the end plate adjacent to said diffusion plate having a hub thereon, means associated with said diffusion plate and hub forming a gas seal, and fan blades mounted on said hub.

8. A muffler for internal combustion engines comprising a casing, said casing including end plates and having inlet and outlet ports therein, bearings carried by the end plates, a shaft mounted in said bearings, a rotor carried by said shaft, a sleeve carried by each of said end plates in which said shaft is freely rotatable, and a diffusion plate mounted on each of said sleeves between the adjacent end plate and the rotor, said diffusion plates having holes therethrough and being supported by said sleeves with their marginal edges spaced from the inside of the casing.

9. A muiller for internal combustion engines comprising a casing, said casing includin end plates and having inlet and outlet ports therein, bearings carried by the end plates, a shaft mounted in said bearings, a rotor carried by said shaft, a sleeve carried by each of said end plates in which said shaft is freely rotatable, a difiusion plate mounted on each of said sleeves between the adjacent end plate and the rotor, said diffusion plates having holes therethrough and being supported by said sleeves with their marginal edges spaced from the inside of the casing, said rotor comprising end plates and buckets extending therebetween, and helical vanes surrounding the shaft in the center of the rotor.

10. A muiller for internal combustion engines comprising a casing, said casing including end plates and having inlet and outlet ports therein. bearings carried by the end plates, a shaft mounted in said bearings, a rotor carried by said shaft, a sleeve carried by each of said end plates in which said shaft is freely rotatable, a perforated diffusion plate mounted on each of said sleeves between the adjacent end plate and the rotor,

said rotor comprising end plates and buckets extending therebetween and helical vanes surrounding the shaft in the center of the rotor, said helical vanes comprising right hand and left hand portions meeting at the center.

11. A muffler for internal combustion engines comprising a casing having end walls and inlet and outlet ports in the casing, struts projecting from the end walls, bearings carried by said struts and spaced from said end walls, a shaft mounted in said bearings and passing through the end walls of the casing, a rotor mounted on said shaft adjacent to the inlet port in the casing, dust collars fixed on the shaft adjacent to said bearings, and fan blades carried by said dust collars.

12. A mufller for internal combustion engines comprising a casing having end Walls and inlet and outlet ports in the casing, struts projecting from the end walls, bearings carried by said struts and spaced from said end walls, a shaft mounted in said bearings and passing through the end walls of the casing, a rotor mounted on said shaft adjacent to the inlet port in the casing, dust collars fixed on the shaft adjacent to said bearings, fan blades carried by said dust collars, perforated diffusion plates in the casing between the end walls thereof and the ends of the rotor, and spaced from said end Walls and from said rotor, and fan blades carried by the rotor between the diffusion plates and the ends of the rotor.

13. A muiiier for internal combustion engines, including a casing having a tangential inlet port and an outlet port therein and a rotor mounted for rotation in the casing, said rotor having a plurality of concavo-convex buckets therein of 7. substantially semi-circular dimensions, said buckets having baflies extending substantially tangential from the convex sides thereof near the outer edges of said convex sides, and terminating substantially in the planes of the mouths 5 of the following buckets.

THOMAS K. CORLESS.

REFERENCES CITED The following references are of record in the 19 file of this patent:

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