US2037459A - Valve for eliminating odor and smoke in exhaust gases - Google Patents

Description

April 14, 19360 CRABB 2,037,459

VALVE FOR ELIMINATING ODOR AND SMOKE IN EXHAUST GASES Filed May 2, 1932 2 Sheets-Sheet 1 gwuantoo L. M. CRABB I April 14, 1936.

VALVE FOR ELIMINATING ODOR AND SMOKE IN EXHAUST GASES Filed May 2, 1932 2 Sheets-Sheet 2 3 7 a a a m a 0 fl I 2 a 8 2 I M 7 y m Patented Apr. 14, :I1Q36 VALVE FOR ELIMINATING ODOR AND SMOKE IN EXHAUST GASES Lester M. Crabb, Flint, lvlich., assignor to Gen eral Motors Corporation, Detroit, Mich., a corporation .of Delaware Application May 2 1932 Serial No. 608,649

2 Claims. (Cl. 137-153) When the throttle valve of the carburetor of an internal combustion engine is suddenly closed, the exhaust gases become smoky and acquire an obnoxious odor. My experiments have shown that, to a large extent, the smoke and obnoxious odor are the result of the presence of incompletely burned fuel in the exhaust gases.

This invention relates to a method of and apparatus for. eliminating incompletely burned fuel and the smoke and obnoxious odor which result therefrom from the exhaust gases of an internal combustion engine during periods of rapid deceleration. i

I have found that the presence of incompletely burned fuel in the exhaust gases of an internal combustion engine during periods of rapid deceleration is the result of the failure to supply, during such periods, suflicient air to the cylinders of the engine to completely burn the fuel supplied thereto. My experiments have further shown that this condition can be remedied and the smokiness and obnoxious odor of the exhaust gases resulting therefrom can be eliminated, without affecting the ratio of fuel to air in the combustible mixture supplied tothe cylinders of the engine at any other time than during periods of rapid deceleration, by admitting to the induction system of the engine on the engine'side of the carburetor, during periods of rapid deoeleration only, sufficient air to insure complete combustion of all of the fuel supplied to the cylinders of the engine. The fact that, during periods during which deceleration is so rapid that there is sufficient incompletely burned fuel in the. exhaust gases to cause smokiness and obnoxious odors, the pressure in the induction system of an internal combustion engine on the engine side of the carburetor is considerably lower than at any other time during the opera- 0 tion of the engine makes it possible to employ very simple mechanism to effect the admission of air during such periods without affecting the operation of the engine at any other time. In its simplest form, the mechanism may consist merely of a passage through which air may enter the intake manifold of the engine from the atmosphere and a valve urged by the pressure of the atmosphere, from a position in which the passage is closed to a position in which it is open, against the intake manifold pressure and the resistance of a spring which is of such strength that the pressure of the atmosphere will be sufficient to open the passage only when the intake manifold pressure reaches a value below that which it assumes at any time other than when deceleration is so rapid that sufficient incompletely burned fuel would occur in the exhaust gases to cause them to be smoky and have an obnoxious odor. However, since, when the passage is open, the pressure in the intake manifold 5 immediately rises, it is preferable, in order to maintain the passage open sufficiently long to admit to the intake manifold sufficient air to insure complete combustion of all of the fuel which enters the cylinders of the engine during 10 the period under consideration, to construct and/or arrange the valve so that a smaller difference in pressure is necessary to maintain it in the position in which the passage is open than to move it to this position from the posi- 15 tion in which the passage is closed.

For a better understanding of the nature and objects of the present invention, reference is made to the following description of the preferred forms of 'airadmission mechanism which are illus- 20 trated in the accompanying drawings.

In the drawings: Figure 1 shows an internal combustion engine on whose intake manifold there is installed air admission mechanism in accordance with my 25 invention. 1

Figure 2 is an enlarged fragmentary transverse section through the installation shown in Figure 1, taken on the line 2-2 of Figure 3.

Figure 3 is a section taken on the line 3-3 of 30 Figure 2, showing the valve in closed position.

Figure a is a section taken on the line $4 of Figure 2, showing the valve in open position,

Figure 5 is a perspective view of a second form of air admission mechanism.

Figure 6 is a perspective view of a third form of air admission mechanism.

Figure 7 is a section similar to Figure 3, but showing a fourth form of airadmission mechanism.

Figure 8 is a section taken on the line t-d of Figure 7.

Figure 9 is a section similar to Figures 2 and 8, but showing a fifth form of air admission mechanism. 45

In the drawings, 1 have illustrated the mechanism for admitting air to the induction system of an internal combustion engine on the engine side of the carburetor during periods of rapid deceleration as applied to the propelling engine 59 of an automotive vehicle because it is particularly useful in connection with such an engine since more people are subjected to the effects of its exhaust gases than to the exhaust gases of sta ionary engines. On the engine, there is 55 installed a duplex" carburetor III of which each mixture passage is connected through one of the passage in the passages II and I2 of an'intake manifold l5 to intake ports of the engine.

The air admission mechanism which is illus-- trated in Figures 1 to 4 of the drawings includes a body I4 in which. there is provided a cylindrical bore I 5 which extends from one end of the body to a point adjacent the other end. The open end of the bore is closed by a head l5 which carries a pin I! which projects axiallyinto the bore. Into the closed end of the bore l5, there extends a form of a bore II which is of smaller diameter than and disposed coaxially with respect to the bore l5. Over the outer end of the passage l8, there is disposed a dirt exeluding shield is. Within the bore l5, there I is snugly fitted to slide a piston valve on whose head end there is provided a coaxial extension 2| of reduced diameter which is adapted to fit passage l8. A coil spring 23, of

tion in which it is shown in Figure 3 of the drawings. Through the bottom of the body l4 into the bore l5 at such points that they are covered erably provided on the upper surface of the manifold l3 directly above the riser, a plane surface through which into each of the pasages I I and 12 To install the air admission mechanism hereinbefore described on the manifold l3, the former is seated on the plane surface with one of the bores 24 in axial alignment with each of the bores 25 and then secured in place by screws 21 which on the body and into the manifold.

The air admission mechanism 28 which is illustrated in Figure 5 is adapted to be installed in body and a groove course, be understood that the plane lustrated in Figures 'l'and 8 does to 4 and differs from to 4 only. inthat bores 24 and the the piston valve is adjacent the head end are eliminated and in that the groove 35 in Figure 5 is replaced by a slot 32 which extends completely through the bottom of the body. v

The air admission in 33 which is ilnot differ essentially from that which is illustrated in the precedingflguresexceptinthat thetwo bores 24 extend through ears of the body surfaceon are replaced by a single threaded bore 34 and in I that communication between the bore 34 and the space between the head and the piston valve 25 is established by intersecting bores 35 and 36. To facilitate installation of the mechanism illustrated in Figures 7 and s, thereis provided in the manifold 31 directly above the riser, a threaded bore 35 which enters both of the passages I I and I2. The mechanism 33 is preferably connected to the manifold by a hollow externally threaded fitting 38- which is screwed into the threaded bores 34 and 38.

The air admission trated, in Figure, 9 of the drawings, includes a cylindrical body 4| in which there is provided a cylindrical bore 42 which extends from one end thereof to a .point adjacent the other end and on which there is provided a reduced coaxial threaded extension 43 through which there extends coaxially into the bore 42 a bore 44, which is of smaller diameter than the bore 42.

Into the end of the body 4| opposite that on which the extension 43 is provided; there is threaded an annular valve seat 45. Within the bore 42, there is located a valve 46 which has a longitudinally grooved cylindrical body which is adapted to slide in the bore 42 and a tapered outer end which is adapted to seat on the walls of the opening in the seat 45. A coil spring 41 which is located within the bore 42 urges the valve 45 to the position in which the drawings in which it functions as a closure for the opening in the seat 45.

The air admission mechanism which is illustrated in. Figure 9 is adapted to be installed on the manifold 45 by screwing the extension 43 into a threaded opening 45 which communicates with both of the branches I I and (2 of the manifold.-

It will be noted that the valves 20 and 46 of the air admission mechanisms illustrated in the drawings and hereinbefore described are so disposed that they may be moved from positions in which they permit the passage of air from the atmosphere into the passages II and I2 of the intake manifolds (through the passage l5 and the bores I5, 24, and 25 in Figures 1 to 5; through the opening l5. thebo're ii, the slot 32 and the bores 25 in Figure 6; through the opening l5 and the bores I5, 34 and 35 in Figures 7 and 8; and through the opening in the seat 45, the grooves in the valve 45 and the bores 42, 44, and 48 in Figure 9) to positions in which they prevent the passage of air from the atmosphere into the passages II and I2. It will be further observed that the springs'23 and 41 urge the valves 25 and 45 to the latterpositions and that since the pressure of the atmosphere is applied to the outer ends of the valves and the pressure within the passages H and I2 to the inner ends of the valves (through bores 25 and 24 and the groove tends to moveffiievalves to the former pomtions.

which lation is so rafild that suilicient in- As hereinbefordhhentioned, the pressure within the 'andl2dui-ing peiiodsduring completely burned fuel 'wouldoccur in the exhaust gases to cause them to be men and have an obnoxious odor is considerably lem than at mechanism which is illusbores 43. 44, and 42 inFigure 9) ,ressurewithinthepassages H and I2 difference between the pressure of the atmosvphere on the portions of the valves on which it.

is exerted when the valves are in positions in which the passages which connect passages II and I2 to the atmosphere are closed. arid the pressure within the passages II and I2 will move the valves to such positions that they will permit the entrance of air into the passages only when the difference between the pressure of the atmosphere and th pressure within the passages exceeds that whi h obtains under any other conditions oi pptration of the engine. It will, of

course, beobvious that the admission 01' air will.

begin only when the difference between the pressure of the atmosphere and the pressure within the passages H and I2 exceeds this predetermined value, but that since, when the valves reach positions in which the passages which connect'the passages II and I! with the atmosphere are open, the areas of their end surfaces on which the pressure of the atmosphere is exerted are greater than those on which the pressure of the atmosphere is exerted when the passages are closed, the valves will remain in the pressure of the atmosphere is exerted when the passages are open and-when the passages are closed, the volume of air admitted to the passages and between the time the valves reach positions in which the passages are openand the time the valves return to positions in which t the passages are closed is determined by the dif- 'ciently larger than the areas of the end surfaces on which the pressure of the atmosphere is ex-- ference between the areas of the end surfaces 01' the valves on which the pressure of the atmosphere is exerted when the passages are open and when the passages are closed. Consequently, while if the areas of the end surfaces of the valves on which the pressure oi the atmosphere is exerted when the passages are open are made sum:-

erted when the, passages are closed, the as will remainopen suillciently long to admit to the passages II and I2 suificlent air to insure complete combustion of all fuel which enters the engine cylinders and to eliminate smoke and odors in the exhaust during periods of rapid deceleration, air will not be admitted to the passages ll and I2 through the passages which connect them with the atmosphere at other times than during periods of rapid deceleration ii the springs 23 and 41 are made ofsuch strength that the difterence between the pressure 01' the atmosphere on the portions of the valves on which it is exerted when the valves are in positions in which the passages which connect the passages II and I2 to the atmosphere are closed and the pressure within the passages II and I 2 will become suflicient to move the valves to positions in which the passages are open only during periods of rapid deceleration.

I claim: 1. In mechanism for regulating admission of to cylinders 01' an'internal combustion engine, a valve housing in which there is provided a bore which is closed to the atmosphere at one end, a smaller bore extending into the other end of the first mentioned bore and communicating with the atmosphere, a valve which fits and is-slidable in the first mentioned bore and on which there is provided an extension which fits and is slidable in the second mentioned bore, a spring urging the valve to a position in which the extension is located in the second mentioned bore, a passage adapted to be connected with the first mentioned passage and extending into the first mentioned bore at such a point that it is closed to .the atmosphere by the valve when the valve is in the position tovwhich it is urged by the spring, and a passage which communicates with the second mentioned passage and the end of the first mentioned bore which is closed to the atmosphere 2. 'In mechanism for regulating admission of air into the passage connecting the carburetor to,

cylinders of an internal combustion engine, a valve housing in whichthere is provided a bore which is closed to the atmosphere at one end, a

smaller bore extending into the other end of the first mentioned bore and communicating with tioned bore at such a point that it communicates with the atmosphere through the mentioned bores when the extension is withdrawn from the second mentioned bore and is closed to the atmospher'e when the valve is in the position to whichitisurgedbythespring.

p LESTER M. CRABB.

15 air into the passage connecting the carburetor

Images