US2465549A - Antidetonating device - Google Patents

Description

March 29, 1949. A. w. ORR, JR

ANTIDETONATING DEVICE 2 Shets-Sheet 1 Filed J1me 14, 1945 H n w 7 r 4.

' March 29, 1949. A. w. ORR, JR-

ANTIDETONATI'NG DEVICE 2 Sheets-Sheet 2 Filed June 14, 1945 3 NR @QNKN bub SN him XWSN QWSQQN R ONQU OQQ 5 MSQ QQNG

AI IZ Orr Jr.

Jib 7.5701

OLL Hd INVENTOR.

Patented Mar. 29, 1949 ANTIDETONATHWG DEVICE Andrew William Orr, Jr., Detroit, Mich., assignor to George Holley and Earl Holley Application June-14, 1945, Serial No. 599,385

The general object of this invention is to provide an airplane carburetor with the means for providing a constant mixture ratio when cruising in the lean or in the rich position and to provide a relatively small addition of fuel when going from the cruising rich to wide open and to provide a relatively larger amount of additional fuel when going from cruising lean. to maximum power, and, finally, to substitute water for the enrichening fuel when developing maximum P er.

The specific object of this invention is to sub- 2 Claims. '(ci. 261-18) stitute for the fuel enrichening device a device goingwide open with the control set in cruising lean! than when set'in cruising rich". In either event, theamount of water consumed per minute should increase with the weight of air. Hence, the same means for maintaining fuel/air ratio constant that is responsive to air flow is made available for maintaining the ratio of water to air constant, so that the air flow regulates the water addition. 7 1

This application contains common subject matter to that disclosed inapplication Serial'No. 581,644 filed March 8, 1945, by George M, Holley, Jr., covering an Aircraftcarbur'etor, and applica tion Serial No. 586,606 filed April 4, 1945, by Andrew William Orr, Jr., covering an Enrichening device. Somewhat similar subject matter is disclosed in Serial No. 622,133 filed October 13, 1945, by'Stanley M. Udale,

Figure '1 shows the preferred form of my inveno FY iIIeIZ shows therelation between the fuel/air ratio'jand airflow with and, without the addition of water. In Figure '1, l0 'i'sfthe' ai'rgentrance, II is the throat of'a venturi; I2 is the throttle, which, wi e; inovedftothe left counteri-cldck'wise, converts theventu'ri ill into'a variable venturi, I3 is one ofa number 'gfopenings into the'thioat of the variable venturi'l l-l2, thus formed, I4 is a passage connecting the orifices l3 with the chambers l5, I5 is a passage parallel to and below the passage l4' and connecting the orifice IS with the chamber l1, 8 is a diaphragm above the chamber l8, I9 is a passage connecting the annular chamber 20 with a chamber 2| immediately above the diaphragm 8, springs 22 and 23 support the diaphragm 8, which carries a metering needle 24, which controls the connection between the chamher It and a passage 18, which communicates with a chamber 38.

The annular chamber 20 is in communication with the air entrance It through a large number of openings, one of which is numbered 28, so that the pressure of the air entrance exists in the chamber 2|. This pressure of the air entering the carburetor also exists in a similar chamber 21, in which there is a similar spring 28 and a diaphragm 29 corresponding to the diaphragm 8 and a spring 30 corresponding to the spring 23 and a metering needle 3| corresponding to the needle 24. This needle 3| forms a restricted communication between the chamber l1 below the diaphragm 29 and a passage 32, which communicates through a restriction 33 with the air inlet 'pressure line IS. The passage 32 communicates pipe 32 and on the other side by the suction in the pipe I8. The pressure in the chamber 34 is higher than the pressure in the chamber 36; that is to say, the valve 24 is normally opened to such. a degree as to admit a good deal of the suction in pipe H to the chamber 38, whereas the valve 3| is normally closed and only opens at comparatively high suctions, so that substantially atmospheric pressure exits in chamber 34 when cruising lean or cruising rich.

freely with the passage I8, which, as stated above,

is a suction passage, so that when the bellows 89 expand due to a lowering of the atmospheric pressure in the entrance In, the pressure in the pipes 25 and I8 rises relative to the pressure in the pipe 32, which pressure is not affected by the bellows 39. At. altitude, the influence of the air now on the diaphragm 81 is thus diminished, and

the mixture ratio is thus maintained within the desired limits, that is, approximately constant.

The throttle I2 is rotated by the throttle lever 42, which is connected to the link 48, which in its turn is connected to the link 44 and to the lever 45. This lever 45 and its control disc 45 are shown turned clockwise into a position approaching the wide-open throttle position, and, thus, partially open fuel metering orifices 41 and 48, which are available and admit metered fuel to passages 48 and 58. The manually-controlled valve 11 in the automatic lean position, as shown, obstructs the flow through the restriction 41 and passage 58 by closing the outlet port I55, but permits that metered by the opening 48 to flow freely through the passage 48 and to flow into the chamber I58 through the open port I54. This metered fuel, together with the small quantity of fuel which flows through a bypass past a low-speed adjusting needle 52 into passage 48, communicates through the port I54 with the chamber 58 to the right of a diaphragm 54, which is to the right of the fuel entrance chamber 55, which communicates with a fuel entrance 58 through a fuel venturi 51. Hence, the diaphragm 54 is subject to the pressure drop at the orifice 48 or at orifices 41-48 when valve 11 is moved counter-clockwise to open port I55 to the automatic rich position.

The servomotor valve 58 engages through the diaphragm 82 with the pin 58. The pin 58 engages through the diaphragm 31 with the pin 88, which pin 88 engages through the small diaphragm I58 with the pin'8I. the flow shall be regulated, servomotor valve 58 controls the flow of metered fuel from an orifice 85, through a passage 84, past valve 58 to a passage 81, which communicates with a chamber 88 below the valve 88. The pressure in the passage 84 and in a chamber 83 connected thereto is equal to the pressure of the metered fuel in the passage 48 less the drop at the restriction 55. This drop is controlled by the valve 58. The pressure thus regulated in chamber 83 acts on In order that adiaphragm I48. and a spring I88 tends to seat the valve 88. When the fuel flow is excessive compared with the air flow, then the fuel pressure acting on the diaphragm 54 pushes the valve 58 over to the right, out of the position shown, overcoming the air pressure difference due to air flow acting on diaphragm 81. The valves 88 and 58 then partly close as diaphragms 54 and 81 move to thevright. When the flow through 84 and 81 is restricted or stops, the pressure in the chamber 831 rises until eventually it eouals the pressure in the chamber 53, which controls and restricts the flow past the valve 85. The fuel, thus regulated, flows to the outlet chamber 88, in which is located a valve 18, mounted on a diaphragm 14. to the left-hand side of which is a chamber I. which communicates through the passage 12 with the unmetered fuel in chamber A spring 13 tends to push the d aphragm 14 to the left and thus o ens. the valve 18, wh ch allows fuel to flow through the passage I48 to the eng ne. The m xture control valve 11 is controlled by a lever 18. When the valve 11 moves clockwise, it moves into the idle cut-off osition; when the valve 11 moves counter-clockwise. it moves to the automatic rich position (A. R). As shown, it is in the automatic lean position.

Valve I1 is connected through the link 84 to the lever 85, which controls the rotation of the valve 88. In the position shown, in the center of the valve 88 is a passage communicating with richer as the fuel and air flows increase. Otherwise, the engines would become overheated. Obviously. at maximum fuel flow and at maximum air flow, fuel economy is of very minor importance, the major importance being, given to power and the greatest importance being given to preventing the engine burning up, and, of course, a rich mixture'is much cooler than a mixturewhich gives perfect combustion.

The fuel flowing through 81 flows out of the chamber 85 to the right of the diaphragm 88. which chamber 85 communicates with the fuel entrance 58 through the passage 81. The fuel flow through the restriction 82 and passage 88 escapes past the diaphragm I81. The chamber 88, to the left of diaphragm 88. communicates with the throat of the venturi 51 through the restricted orifice 88. Valve I88 is carried by the diaphragm 88 and is seated by a compression.

spring I 8| in the chamber 88. so that the flow through the venturi 51 must be great enough to compress the spring "I; otherwise, the valve I88 will not open, so that the valve I88 only opens at high air flows and when the fuel flow is correspondingly high.

A passage I82 connects with the restricted orifice 88, and in the position shown is inoperative. when the lever 85 is moved counterclockwise into the automatic rich position (A. R), an opening I88 invalve 88 allows fuel to flow towards orifice 88 and along .the passage I82 from the passage I84. The jet numbered I88, located in the passage I84, which communicates with the chamber 55, is an important restriction in the fuel metering system. Restriction 88 is inserted only to make the jet m oi'smeu enough size. The new through the restriction I88, through the. passage I88. through the passage I82, increases the pressure in the chamber 88,

- so that the valve I88 will not'open so much in .the cruising rich position for the same fuel flow through the venturi 51, nor will it commence to open until the fuel flowfis greater. Jet, 88 can be omitted if the suction holes in the venturi throat 51 are of the proper size and are held to close limits in production. The lower right-hand corner of Figure 1 shows the construction for the control of the water that takes the place of the enrichening fuel The outlets from the two restrictions III-82 are conveyed through a common passage 88to' the chamber 84. When the diaphragm I 81 closes When valve 11 is rotated anti-clockwise 45, fuel g is also admitted from the var ab e restr ction 41, so that the fuel flow throu h both 48 and 41 (mntrols the pressure in chamber I53. This is the autamatic richposition (A. R).

the right-hand outlet of the passage 83. 'no amount of fuel from the needle I88 is admitted to the chamber 88. The water in the bottom of the tank I14 is admitted through the pipe I8! past the valve I82, controlled by the solenoid I88, which is controlled by the manually-operated,

pilot's switch in. When the valve I82 isopened.

water flows up through the passage'i 85 to the e s u a us t ame h water is transmitted down through the pipe I88 to the chamber I88 to the right of. diaphragm I01, so that the diaphragm I01 responds to the pressure thus transmitted and closesthe end of the passage 83 and compresses the spring I08.

' I84. The slot I85 is connected through a. passage I88 to a corresponding slot I81, which, in the position shown, is wide open.

Valve I88 in the position shown, has completely uncovered the slot I83. A lever I89 is connected by the rod I80 with the lever 18; the posi-' tion of this lever 18, which is shown in the automatic lean position, determines whether the controls are in automatic rich, automatic lean or the idle cut-ofl position. The diaphragm I, which controls the movement of the balanced valve I88, is responsive to the pressure in the chamber I12. The pressure in the chamber I12 is determined by the pressure in the passagel13, which is connected to the chamber 53, which is the pressure of the fuel on the downstream side of opening 48. The supply of water under pressure is obtained indirectly from the fuel pump I15, which dis-' charges fuel up the passage I18, which communicates to the upper part of the water tank I14 and thus pushes the water out of the bottom of the water tank I14 into the passage I8I. The pressure relief valve I11 prevents the fuel pressure becoming excessive. The pipe I18 communicates with the fuel entrance 58.

Operation The switch I84 being closed, the valve I82 is opened by the solenoid I83. Then, as the throttle is opened, slots I8I and I85 are opened so that more and more water is admitted to the chamber I18. In the position shown, which is the automatic lean (A. L.), both slots I83I81 are wide open, so that the maximum amount of water is flowing. When the lever 18 moves anti-clockwise to the automatic rich position (A. R.), the valve I88 also moves anti-clockwise and completely closes the slot I81. Slot I83 remains wide open; by this means, less water is admitted in the automatic rich, as, in the automatic lean position, more water is needed as the engine is more prone to detonate with a lean mixture than with a rich mixture. When the valve 11 and I88 are moved clockwise, then both the slots I83 and I81 are completely covered. This is the position for idle cut-off.

The function of the pipe I13 is to insure that the pressure in chamber I18 is equal to the pressure in the chamber 53. Hence, the drop of pressure through the restrictions I85 and I8I is the same as the drop in pressure past the restrictions 41 and 48. The pressure upstream from the restrictions I8I and I85 is the pressure in the pipe I18 because the water tank I14 is freely opened to the passage I18 and the valve I82 is wide open. Hence it is that the flow of water increases as does the flow through the orifice 48 and the flow through the orifice 41. The only difference is that when the fuel orifice 48 alone is used, both the restrictions I8I and I85 are functioning,

Rich-no water 1. A, B, C, D, E.The vale I82 is closed and the controls 11, 88 and I88 are in their rich position, that is, about 30 anti-clockwise from the position shownin Fig. 1. From A to B there is 'an empirical relationship between fuel flow and airflow in the idle and 0115 idle range. From B to C the fuel/air ratio is determined by the counter balanced diaphragms 54 and '31.and by the size of the variable orifices 41 and 48 which are opened in a fixed relationship with the air throttle (I2. From C to D the power enrichment valve I88 opens against spring IOI by means of differential from venturi 51, reduced by restrictions 98 and I80. The maximum fuel/air ratio attained at D occurs when valve I00 is wide open at which time restriction 8|, together with variable orifices 41 and 48, governs the fuel fiow. Note the restriction 92 is now out of action as less enrichment is needed with the rich cruising mixture of 0.080 B-C.

Rich-with. water ture. When thesolenoid I83 is energized by switch I84 to open water admission valve I82, all fuel flow through valve I08 and restriction 9| is out of! by water pressure operated diaphragm valve I01. The fuel/air ratio shown on line BC is due to variable fuel restriction 41 and 48. Unmetered fuel pressure in chamber 58 is impressed on water tank I14 and hence exists in unmetered water passage I85. Metered fuel pressure from chamber 53 is led by pipe I13 to chamber I12. Water regulating diaphragm I1I actuates water control valve I88 to adjust water flow across throttle operated water restriction I8I to give metered water pressure in chamber I18 equal to metered fuel pressure in chamber 12. Water restrictions I8I and I85 are of sufiicient size to bring combined ratio of water and fuel to air ratio to line DE on Fig. 2. Switch I84 is energized only when the engine is operated at airfiows in excess of of maximum as below this point there is no need to use water.

Lean-no water 3. A, F, G, D, E.--The valve I82 is closed and the controls 11, 88 and I88 are in the position shown in Fig. 1. From A 'to F there is an empirical relationship between airflow and fuel/air ratio determined by throttle operated restriction 48 and parallel adjustable valve 52. From F to G the fuel/air ratio is determined by the two diaphragms 54 and 31 and bythe throttle orifice 48 as throttle operated orifice 41 is closed by control 11. From G to D the power enrichment valve I00 opens against spring IN by means of full difierential pressure from venturi 51 as restriction I80 is closed by control 88. The maximum fuel/air ratio attained at D occurs when valve I88 is wide open at which time restrictions 5i and 92, together with variable orifice i8, gov

ern the fuel/air ratio.

Lean-with water 4. A, F, G, G E.-The valve I52 is open and pressure operated diaphragm valve I01 closes ofir all fuel from restrictions 9! and 92 in a previously described manner. The fuel/air ratio is now as shown on line 6-6 and is determined by the variable fuel restriction 68. However, both parallel throttle operated variable water restrictions I8I and I85 add metered water to the system in a manner previously described to bring the total water and fuel/air ratio up to the line DE on Fig. 2. Switch I6 3, as before, is energized only when the engine is operated at airfiows in excess of 95% of maximum as below this point there is no need for water.

What I claim is:

1. An engine fuel supply system comprising an air intake, an air restriction therein, a source of fuel under pressure, a fuel supply passage con.-

nected thereto, a fuel restriction, means respon sive to the drop in pressure therein, automatic 30 2,142,979

means responsive to the depression in said air restriction acting to balance said means responsive to the drop in pressure at said fuel restriction, means responsive to the unbalance to vary the pressure downstream from said fuel restriction so as to maintain the desired fuel/air ratio, a. source attests as the source of fuel, a passage therefor, means for introducing the anti-detonating fluid into the air entering the engine comprising a restriction in said passage, automatic means for maintaining the pressure downstream from said fluid re striction equal to the pressure downstream from said fuel restriction, a first valve controlling the size of said fuel restriction, a second valve c0n-= trolling the size of said anti-detonation fluid restriction mechanism interconnecting said valves for simultaneously opening said second valve and v closing said first valve whereby when the first valve is moved in the direction to reduce the area of said fuel restriction then the second valve is moved so as to increase the area of said fluid restriction.

2. A device as set forth in claim 1 in which i there areinterconnected means for simultaneous- 25 The following references are of'record in'the' Number Name Date Hans Jan. 3, 1939 2,361,227 Mock Oct. 24, 1944 v 2,372,356 Chandler Mar. 27, 1945 1 1 2,379,984 Schmn Apr. 9,1946 FOREIGN PATENTS Number 1 Country Date of anti-detonating fluid under the same pressure 1y varying the restriction in the air stream, the restriction in the fuel passage and the restriction in the passage for anti-detonating fluid.

' ANDREW 'l ORR, Ja. I

REFERENCES CITED file ofthis patent: I UNITED STATESPATENTS France May 18, 1938

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