US2993485A

US2993485A - Intake manifold vacuum actuated fuel shut-off apparatus

Info

Publication number: US2993485A
Application number: US825620A
Authority: US
Inventors: George W Cornelius
Original assignee: Holley Carburetor Co
Current assignee: Holley Performance Products Inc
Priority date: 1959-01-12
Filing date: 1959-01-12
Publication date: 1961-07-25
Anticipated expiration: 1978-07-25

Description

July 25, 1961 G. w. CORNELIUS INTAKE MANIFOLD VACUUM ACTUATED FUEL SHUT-OFF APPARATUS Filed Jan. 12, 1959 4 Sheets-Sheet 1 WW mm 5 mm 6 a 7 I. E r V r: M me: 0 a i W 1 1, Z ma CJY B QQN 3% INTAKE MANIFOLD VACUUM ACTUATED FUEL SHUT-OFF APPARATUS Filed Jan. 12, 1959 July 25, 1961 G. w. CORNELIUS 4 Sheets-Sheet 2 INTAKE MANIFOLD VACUUM ACTUATED FUEL SHUT-OFF APPARATUS Filed Jan. 12, 1959 July 25, 1961 G. w. CORNELIUS 4 Sheets-Sheet 3 INVEN TOR. 6 5024: I4 foe/via:

Y a 6 W r/m 4.: 0 M 1 W a Y B July 25, 1961 G. w. CORNELIUS 2,993,485

INTAKE MANIFOLD VACUUM ACTUATED FUEL SHUT-OFF APPARATUS Filed Jan. 12, 1959 4 Sheets-Sheet 4 2,993,485 INTAKE MANIFOLD VACUUM ACTUATED FUEL SHUT-OFF APPARATUS George W. Cornelius, Palos Verdes Estates, Calif., as-

signor to Holley Carburetor Company, Van Dyke,

Mich.

Filed Jan. 12, 1959, Ser. No. 825,620 19 Claims. (Cl. 123-97) The present invention relates generally to internal combustion engines and more particularly to a method and apparatus to control the admission of fuel thereto so as to reduce the volume of contaminants released thereby.

It is well known that the unburned contaminants exhausted from internal combustion engines of automotive vehicles constitute a prime source of the so-called smog which exists in and around the principal population centers of the country. The harmful effects of this smog upon animate and inanimate objects are likewise very well known. Since the inception of smog and the recognition of its detrimental eifect upon health and plant life, extensive research has been conducted in order to determine how the internal combustion engines contribution to smog could be successfully diminished. Considerable attention has been devoted to the deceleration cycle during which time the largest percentage of unburned products of combustion are exhausted from the engine. This large percentage results from the fact that during deceleration the fuel entering the engines combustion chambers does not undergo complete burning. Accordingly, unburned hydrocarbons are exhausted into the atmosphere where they contribute substantially to the smog content thereof. Additionally, these unburned hydrocarbon products form carbon deposits within the combustion chamhers, exhaust valve ports and the remainder of the exhaust system. These disadvantages are in addition to the reduction in mileage resulting from the considerable loss of fuel from the carburetor during deceleration, such fuel being drawn from the idling system of the carburetor because of the extreme vacuum created in the intake manifold during deceleration.

For the foregoing reasons it has been heretoforeproposed to provide automatic shut-off devices for positively stopping the flow of fuel to an engine undergoing deceleration. With most of the heretofore-proposed fuel shut-01f devices a decided fiat spot ormomentary lack of power is experienced when the accelerator is opened after a period of deceleration. This inability to effecta smooth recovery is generally caused by the time lag required to change the fuel in the idling system from a static condition to a moving condition. These heretoforeproposed fuel shut-off devices likewise generally fail to provide the engine with suflicient fuel to adequately rewet the dried-out intake manifold after a period of deceleration, which failure is also partially responsible for the aforementioned flat spot.

It is a major object of the present invention to provide an improved intake manifold vacuum actuated apparatus for controlling the admission of fuel and air to the internal combustion engine of an automotive vehicle during and immediately after a period of deceleration.

A further object of the present invention is to provide apparatus of the aforedescribed nature which is entirely automatic in operation, requiring no attention from the driver of the automotive vehicle.

Another object is to provide a fuel shut-01f apparatus of the aforedescribed nature which is comparatively simple in design and rugged of construction whereby it may afford a long and trouble-free service life.

A further object is to provide fuel shut-off apparatus of the aforedescribed nature which is fool-proof and ef:

ficient in operation under all driving conditions.

United tat Patented July 25, 1961 Yet another object of the invention is to provide fuel shut-off apparatus of the aforedescribed nature which may be readily installed upon the engine of existing automotive vehicles, or, alternatively, may be incorporated into original equipment.

A further object of the invention is to provide fuel shut-off apparatus of the aforedescribed nature which requires a minimum of maintenance once it has been installed.

Yet a further object of the present invention is to provide fuel shut-0E apparatus of the aforedescribed nature which is not affected by a change in altitude of the automotive vehicle whereon it is mounted.

Yet another object of the invention is to provide fuel shut-off apparatus of the aforedescribed nature which may be manufactured by mass production methods at a comparatively low cost whereby it may find a wide market.

A more particular object of the present invention is to provide fuel shut-off apparatus of the aforedescribed nature which is operable at a minimum intake manifold vacuum differential and which will not be subject to inadvertent operation other than during decelerating of the engine.

Another more particular object of the present invention is to provide fuel shut-off apparatus of the aforedescribed nature that first re-wets the intake manifold with liquid fuel at the end of a deceleration period and thereafter introduces liquid fuel and air into the intake manifold in excess of that required for normal idling so as to aiford constant smooth operation of the engine.

These and other objects and advantages of the present invention will become apparent from the following detailed descriptions when taken in conjunction with the appended drawings wherein:

FIGURE 1 is a side view, primarily taken in vertical section showing a preferred embodiment of fuel shutoff apparatus embodying the present invention and depicting the arrangement of the parts thereof during idling of the engine whereon it is installed;

FIGURE 2 is a view similar to FIGURE 1, but showing the parts of said apparatus at the beginning of a deceleration peiiod; and

FIGURES 3 and 4 are views similar to the preceding figures, but showing the parts of said apparatus during later stages of a deceleration period.

General arrangement Referring to the drawings and particularly FIGURE 1 thereof, the preferred form of fuel shut-ofi apparatus embodying the present invention is adapted for use with a fuel-supplying device of an automotive vehicle such as a conventional carburetor C (a portion of which is shown). The carburetor C includes one or more barrels 10 wherein is disposed a conventional butterfly-type throttle valve 12 supported upon a horizontal shaft 14. The shaft 14 protrudes through the walls of the carburetor C so as to receive the accelerator pedal linkage (not shown) of the automotive vehicle in a well-known manner. The throttle valve 12 is pivotable between its closed or idling position shown in solid outline in FIGURE 1 and an open The preferred form of fuel shut-01f apparatus embodying the present invention includes an air-fuel shut-ofl member S and a regulator member R operatively connected with member S. Both members S and R are mounted adjacent the carburetor C in a suitable manner and the air-fuel shut-ofl member S is adapted to effect a positive stoppage of the fuel flowing through the carburetor barrel 10 through its idling duct 16 during deceleration of the engine. At the conclusion of the decelerating period the air-fuel shut-off member S is adapted to automatically control the air-fuel ratio of the fuel mixture so as to positively prevent rough operation of the engine. The motivating force for operating the air-fuel shut-cit member S is the intake manifold vacuum of the engine, while the sensing means for controlling the operation of the air-fuel shut-off member S is the regulator valve R.

The air-fuel shut-01f member S The air-fuel shut-ofi member S is partially defined by a lower body-piece 20 and an upper body-piece 22, with such body-pieces being suitably afixed together. The body-

pieces

20 and 22 are formed with facing cylindrical cut-out portions 24 and 26, respectively, which cooperatively define a diaphragm chamber 28. The upper portion of the cut-out portion 26 merges into a coaxial spring cavity 30 of smaller diameter wherein is disposed a coil compression spring 31. The spring cavity 30 merges into a coaxial timer bore 32 of yet smaller diameter. The upper end of the timer bore 32 is in communication with a timer chamber 33 that is defined by the interior of a cap 34. This cap 34 is rigidly afiixed to the upper portion of the body-piece 22 by suitable means. The lower body cut-out portion 24 merges into a coaxial bore 36 that vertically slidably receives the stem 40 of a shut-off valve 42. The lower portion of the stem bore 36 is of enlarged diameter so as to form an annular fuel bypass 44. At the lower end of the fuel bypass 44 there is defined a downwardly extending lip 46. Below the lip 46 there is formed an air-fuel distribution chamber 48.

The upper portion of the shut-01f valve 42 is affixed to a diaphragm 50 formed of a suitable flexible material, such diaphragm 50 being interposed between a pair of annular keeper elements 52 and 53. The radially outer portions 'of'the diaphragm 56 maybe sandwiched be tween the upper and lower body-

pieces

20 and 22 by suitable means. The lower portion of the valve stem 40 is formed with a flange 54 from which depends an annular skirt 56. A sealing -ring 58 formed of suitable material is seated upon the flange 54. The upper surface of this sealing ring 58 is adapted to seat against the aforedescribed lip 46 at the beginning of a decelerating period, and the elements 54, 56 and 58 collectively define a shutoff plug that cooperates with the lip 46 to cut-01f downward fluid flow through stem bore 36 and fuel bypass 44. The skirt 56 is formed with one or more fuel-ratio ports 59. The intermediate portion of the valve stem 40 is formed with a pluralityof radially extending ports 60, the inner ends of which are in communication with the hollow interior 62 of the stem 40. The lower portion of the valve stem 40 is formed with a plurality of downwardly and radially outwardly extending ports 64 communicating with its hollow interior 62. The upper end of the valve stem 40 is formed with an upstanding externally threaded post 66 which receives and extends above the diaphragm keepers'52 and 53.

An elongated, generally cylindrical timer member, generally designated 70, is vertically slidably disposed within the aforementioned timer bore 32. This timer 70 includes a generally cylindrical body 72 upon which is vertically slidably carried a complementary generally tubular cover 74. Thebody 72 is formed with a coaxial upwardly-facing cavity 76 wherein is disposed a coil compression spring 78. The spring 78 constantly exerts 4 an upwardly directed force against the upper wall 80 of the cover 74. The upper portion of the cover 74 is formed with a radially outwardly extending flange 82. A coil compression spring 84 extends upwardly from the flange 82 to the upper wall 86 of the cap 34 so as to constantly exert a downwardly directed force upon the cover 74. A seal ring 88 of suitable material is aflixed to the underside of the flange 82. This seal ring 88 is adapted to engage a suitable seat 90 formed at the upper end of the timer bore 32.

A vertically extending timing orifice passage 92 interconnects the lower portion of the timer chamber 33 v with the upper portion of the spring cavity 30. The opposite side of the timer chamber 33 is in communication with a high vacuum passage 96 extending through the body-

pieces

20 and 22. The out-out portion 24 of the body-piece 20, i.e., the portion of the diaphragm chamber 28 below the diaphragm 50, is in communica-. tion with a lead time passage 98 formed in the lower body-piece 20 by means of a bore 100 wherein is disposed the stem 102 of a reset valve 104. A coil compression spring .106 constantly biases the reset valve 104 upwardly against a seat 106 formed at the lower end of the bore 100. The body cut-out portion 26, i.e. the portion of the diaphragm chamber 28'above the diaphragm 50, is in communication with the lead time passage 98 by means of a passageway 110. The passageway 110 intersects a check valve cavity 112 wherein is disposed the head 114 of a check valve 116 having a stem 118. The head 114 is movable downwardly so as to engage a suitable seat 120 formed at the lower portion of the cavity 112. The stem 118 of the check valve 116 is constantly biased downwardly by a small coil compression spring 122 that abuts an enlargement 124 formed at the lower end of the stem 118.

The body cut-out portion 24, ie the portion of the diaphragm chamber 28 below the diaphragm 50, is in communication with the atmosphere by means of a generally horizontally extending passage 140, the outer end of which merges into a fitting 142 that receives a suitable conduit (not shown) connected to the air cleaner of the engine. The portion of the diaphragm chamber 28 below the diaphragm 50 is also in communication with an air passage 144 by means of a plurality of vertical branch passageways 146 and 148. These branch passageways 146 and 148 intersect the stem bore 36 at a point spaced intermediately of the lower portion of the diaphragm chamber 28 and the upper end of the fuel bypass 44.

The upper end of the fuel bypass 44 is in communi cation with a conduit 149 having its opposite end connectcd with a fuel emulsion passage 150 formed in the walls of the carburetor C. The upper portion of the air-fuel distribution chamber 48 is in communication with a conduit 152 having its opposite end connected wlth the upper portion of an idle discharge passage 154 formed in the walls of the carburetor C. The upper end of the idle discharge passage 154 is connected with the carburetor barrel 10 by a transfer port 156. The lower end of the idle discharge passage 154 is connected with an idle adjustment cavity 158 wherein is disposed an idle adjusting screw 160. The front end of the idle adjusting cavity 158 is in communication with the idling duct '16 of the carburetor C. The lower end of the air-fuel distribution chamber 48 is connected with the carburetor barrel 10 below the throttle valve 12 by a fuel-air discharge conduit 162, the oposite end of this conduit being connected with a bore '164 extending through the walls of the carburetor C. A bore 166 formed in the walls of the carburetor C below the aforementioned bore 164 is connected to one end of a high vacuum conduit 168. At a point immediately below one edge of the throttle valve 12 when the latter is arranged in itsclosed position the walls of the carburetor Gare f ormed a bore 170; V bore 170 connected to one end of a regulator vacuum conduit 172.

The regulator member R The regulator member R includes a generally cylindrical housing 180 having its upper end formed with a top closure 182 that is coaxially formed with a bore 184. The side wall of the housing are formed with one or more vents 185. The lower end of the housing 180 is suitably aflixed -to the aforedescribed body-piece 20 at a point spaced horizontally from the body-piece 22. A diaphragm retainer ring 186 is rigidly mounted within the lower interior portion of the housing 180. The bore 184 receives the externally threaded upper portion of an adjustment post 190, an adjustment nut 192 being provided for the portion of the adjustment post 190 exterior of the top closure 1-82. The lower port-ion of the adjustment post 190 is formed with a disk 194 that supports the upper end of an altitude compensating bellows 196 of conventional construction. The lower end of the bellows 196 is aflixed to a generally cylindrical stern mounting element .198 that is coaxially disposed within the retainer ring 186. The stem mounting element 198 is coaxially formed with a downwardly facing internally threaded vertically extending bore 200. This bore 200 receives the upper end of a regulator stem, generally designated 201, whereon are formed upper and lower lands 202 and 203, respectively. The portion of the regulator stem 201 below the element 198 is aifixed to a bellows diaphragm 204 formed of a suitable flexible material. The bellows diaphragm 204 is retained in place between a pair of keeper elements 206 and 208. The radially outer portion of the bellows diaphragm 204 is sandwiched between the body-piece 20 and the aforementioned diaphragm retainer ring 186. The bellows diaphragm 204 is disposed within a regulator diaphragm cavity 210 defined by facing cylindrical cut-out portions formed in the body-piece 20 and the retainer ring 186. The upper portion of the stem 201 is formed with a stop collar 211 having radially extending flutes 212, said collar being engageable with the lower wall of the cavity 210.

A regulator stern bore 213 coaxially depends from the lower portion of the bellows diaphragm cavity 210. The upper portion of this regulator stem bore 213 is intersected by a horizontal regulator vacuum port 214 which is connected to the end of the regulator vacuum conduit 172 remote from the carburetor C. A regulator vacuum bypass hole 215 interconnects the lower portion of the bellows diaphragm cavity 210 and the regulator vacuum port 214. The regulator stem bore 213 is intersected by a high vacuum port 216 immediately below the aforedescribed regulator vacuum port 214. The end of the port 216 remote from the regulator stem bore 213 is connected with the aforedescribed high vacuum conduit 168.

At a point below the high vacuum port 216, the diameter of the regulator stem bore 213 is enlarged so as to define an annular distribution chamber 220. One side of this distribution chamber 220 is in communication with the aforedescribed high vacuum passage 96. The opposite side of this distribution chamber 220 is in communication with a solid idle passage 222 formed in the body-piece 20. The lower end of the solid idle passage 222 is in communication with a solid idle valve chamber 224. The upper end of this chamber 224 is formed with a seat 226, which is adapted to be engaged by the head 228 of a solid idle valve 230. The stem 232 of the solid idle valve 230 is integrally formed at its lower end with an enlargement 234 disposed in the lower portion of the regulator stem bore 213. A coil compression spring 236 disposed in the bottom of the bore 213 constantly biases the solid idle valve 230 upwardly. Immediately above the solid idle valve cavity 224 the regulator stem bore 213 is in communication with the end of the aforede- 6 scribed air pass age'way 144 remote from 'the diaphragm chamber 28 of the air-fuel shut-off member S.

Above the intersection of the air passageway 144 with the regulator stem bore 213 the body-piece 20 is formed with a lead time port 240. The lead time port 240 intersects the upper portion of a lead time diaphragm chamber 242. The upper portion of the lead time chamber 242 is in communication with the lower portion of the regulator diaphragm cavity 210 by means of a vertically extending lead time orifice passage 244. A lead time diaphragm '246 of suitable flexible material is disposed within the chamber 242. The underside of the diaphragm 246 abuts the head 248 of a lead time valve 250. The lower portion of the lead time chamber 242 below the lead time diaphragm 246 is in communication with the end of the aforedescribed lead time passage 98 remote from the air-fuel shut-oii member S. A coil compression spring 258 abuts the underside of the valve head 248 so as to constantly bias the lead time valve 250 upwardly. A transfer passage 260 is formed in the upper portion of the stem 262 of the lead time valve 250. This transfer passage 260 connects the lead time passage 98 with the upper surface of the head 248 of the lead time valve 250.

Operation Referring first to FIGURE 1, in the operation of the aforedescribed fuel shut-off apparatus, the parts of the apparatus will be disposed in their positions of FIGURE 1 during idling and cruising conditions. At this time, the stem 201 of the regulator member R will be disposed in its raised position, inasmuch as the intake manifold vacuum existing within the carburetor barrel 10 and transmitted to the lower portion of the regulator diaphragm cavity 210 by the regulator vacuum conduit 172, the regulator vacuum port 214 and the regulator vacuum bypass hole 215 is not of suflicient magnitude to overcome upwardly directed force created by the normal tension of the bellows 196. At this time, both the lower and the upper portions of the diaphragm chamber 28 of the airfuel shut-ofi member S will be in communication with the atmosphere. The lower portion of this chamber 28 is connected with the atmosphere by the passage 140, while the upper portion of this chamber is connected with the atmosphere through timing orifice passage 92, the timer chamber 220 of the regulator R, the solid idle passage 222, the solid idle valve chamber 224, the air passage 144, its branches 146 and 148, and the lower portion of the diaphragm chamber 28. Accordingly, the spring 31 of the air-fuel shut-0E member S will maintain the shut off valve 42 in its lowermost position of FIGURE 1. With the fuel shut-off valve 42 arranged in this position, the lower end of the stem 40 will block communication through the fuel-air discharge conduit 162. Therefore, only fuel and air in an amount suificient for normal idling will be permitted to flow through the fuel bypass 44 and, thence, through the conduit 152 into the idle discharge passage 154 of the carburetor C. The exact ratio of fuel and air flowing from the idle discharge passage 154 into the idling duct 16 may be controlled by the idle adjustment screw 160.

It should be particularly noted that the fuel shut-off apparatus embodying the present invention incorporates means for preventing hunting of the shut-ofl valve 42 of the air-fuel shut-off member S. In this regard, and with continued reference to FIGURE 1, with the regulator stem 201 disposed in its raised position, the head 228 of the sol-id idle valve 230 will be raised off its seat 226. Accordingly, the solid idle passage 222 will be placed in communication with the atmosphere through air passage 144, its branches 146 and 148 and the lower portion 24 of the diaphragm chamber 28. The presence of atmospheric pressure at the upper end of the solid idle passage 222 will serve to cancel any etiect of leakage from high vacuum port 216 around the spool 203 and into the high vacuum passage 96 of the air-fuel shut-ofi member S.

7 Itwill be apparent that any leakage around this spool 203 wouldserve to raise the shut-off valve 42 resulting in hunting of this valve and consequent rough engine operation.

Referring now, additionally, to FIGURE 2, upon deceleraticn, the magnitude of intake manifold vacuum will increase to a maximum. This negative pressure will be communicated to the portion of the regulator diaphragm cavity 210 below the diaphragm 294 by means of the conduit 172, the regulator port 214, and the bypass hole 215, as indicated by the directional arrows in FIGURE 2. The magnitude of the intake manifold vacuum is sufficient to overcome the upwardly-directed force of the bellows 196 and, accordingly, the regulator stem 201 will be moved downwardly. Such movement takes place slowly at first because of the comparatively small dimensions of the hole 215. After a short interval of downward movement, however, the upper portion of the top land 2132 of the regulator stem 201 will uncover the upper portion of the port 214. Thereafter, the lower portion of the regulator diaphragm cavity 210 will be directly exposed to the vacuum within the port 214, and the stem 201 will be snapped downwardly to its lowermost position of FIGURE 2.

As the regulator stem 201 moves downwardly its lower spool 263 will uncover the high vacuum port 216. Accordingly, the portion of the regulator stem bore 213 between the spools 202 and 203 will be placed in communication with the high intake manifold vacuum existing within the carburetor barrel 10 below the throttle valve 12 by means of the high vacuum conduit 168. This negative pressure is transmitted from the aforementioned portion of the stem bore 213 to the timer chamber 33 by means of the high vacuum passage 96, as indicated by the directional arrows in FIGURE 2. Additionally, the regulator stems lower end will force the head 228 of the solid idle valve 230 into sealing engagement with the seat 226, thereby blocking communication between air passage 144 and the solid idle passage 222.

The presence of negative pressure within the timer chamber 33 will thereupon serve to overcome the force of the timer spring 84 and lift the cover 74 of the timer 7 to its uppermost dotted outline position of FIGURE 2. Upward movement of the timer cover 74 unseats its seal ring 88 from the seat 90 formed at the upper end of the stem bore 32. Accordingly, the intake manifold vacuum will be immediately transmitted to the upper portion 26 of the air-fuel shut-ofl member diaphragm cavity 28. The downwardly directed force of the spring 31 will then be overcome and the diaphragm 50 will flex upwardly effecting concurrent upward movement of the shut-off valve 42 to its position of FIGURE 2.

After the initial upward movement of the timer 70 to its dotted outline position of FIGURE 2, the timer cover 74 will remain momentarily in this uppermost position under the influence of the air trapped within the timer. Thereafter, the downwardly directed force of the timer spring '84 will overcome the force of the smaller spring 78 so as to collapse the timer cover 74 downwardly and it will return to its solid outline position therein. With the shut-off valve 42 disposed in its uppermost position of FIGURE 2, the sealing ring 58 and the lower portion of the valve stem 40 will be seated tightly against lip 46 formed at the lower end of the fuel bypass 44. Accordingly, all downward flow of fuel through the fuel bypass 44 will be positively cutoff. Concurrently, air will be free to bypass the throttle valve 12 through transfer port 156, idle discharge passage 154, and the idling duct 16. Any excess air may pass into the carburetor barrel below the throttle valve 12 through conduit 152, the air-fuel distribution chamber 48, and conduit 162. By positively blocking off the flow of fuel into the intake manifold of the engine during deceleration the unburned products of combustion emitted from such engine will be reduced to a minimum.

Referring now additionally to FIGURE 3, after a period of deceleration, themagnitude of the intake manifold vacuum existing within the lower portion of the regulator diaphragm cavity 210 will fall below that necessary to maintain the bellows 196 flexed downwardly relative to its original contracted length. Prior to this time the regulators stem 201 will have commenced upward movement to its original position shown in this figure. In this regard, referring again to FIGURE 2, at such time as the intake manifold vacuum is communicated to the upper portion 26 of the diaphragm chamber 28 of the air-fuel shut-off member S, the head 114 of the check valve 116 will have been'lifted off its seat 120. This will serve to place the lead time passage 98 in communication with the intake manifold vacuum thereby causing the diaphragm 246 to move the lead time valve 250 downwardly. Accordingly, the lower end of the lead time orifice passage 244 will be uncovered by the diaphragm 246 and passage 244 will be placed in communication with the atmosphere through lead time port 240, the portion of the regulator stem bore 201 below the lower land 203, air passage 144 and its branches 146 and 148. The passage 244 will therefore admit air at atmospheric pressure into the lower portion of the regulator diaphragm cavity 210. In this manner, the effective value of the intake manifold vacuum within the lower portion of this cavity 210 will be decreased. Accordingly, the regulator stem 201 will be raised into its uppermost position prior to the end of a decelerating period. As the stem 201 completes its upward movement and the upper land 202 closes regulator vacuum port 214, the regulator stern 201 will snap upwardly through its final increment of movement. This arrangement assists in effecting positive operation of the shut-off valve at minimum intake manifold vacuum differential.

This will serve to again connect the interior of the timer chamber 33 with the atmosphere and the valve 42 will snap downwardly to its position of FIGURE 3, the timer seal element 88 then moving into seating engagement with the seat formed at the upper end of the timer bore 32. In this position of the shut-off valve 42, the sealing ring 58 formed at the lower portion of the stem 40 will have been unseated from lip 46. In this position of the shut-off valve the ports 60 have not yet fully coincided with the branches 146 and 148 of the air passage 144. Accordingly, the intake manifold vacuum existing within the carburetor barrel 10 below the throttle valve 12 will exert an appreciable amount of suction upon the solid fuel disposed within the fuel emulsion passage 150, conduit 149, fuel bypass 44, and air-fuel distribution chamber 48. This suction tends to provide a choking pull on the fuel so as to immediately bring the previously static fuel dis posed in the fuel emulsion passage 150, conduit 149 and fuel bypass 44 into motion towards conduit 162 and the interior of the carburetor barrel 10. This position of the shut-off valve 42 may be considered a fuel charging position.

Referring now additionally to FIGURE 4, when the timer seal element engages the seat 90, communication between the upper portion of the air-fuel shut-off members diaphragm chamber 28 and the timer chamber 33 must be through the timer orifice passage 92. Because of the comparatively small dimension of this passage 92, the evacuation of the upper portion of chamber 28 will take place at a low rate and, accordingly, the stem 46 of the shut-off valve 42 will be moved downwardly comparatively slowly beyond its position shown in FIGURE 4 into its position shown in FIGURE 1. As the regulator valve 42 continues its downward movement from its position of FIGURE 3, the ports 60 in its stem 40 will become aligned with the portions of the branch passages 146 and 148, intersecting stem bore 36, as indicated in FIGURE 4. Additionally, the lower portion of the skirt 5-6 will be telescopically received by the upper portion of the air-fuel distribution chamber 48. Accordingly, atmospheric air will be drawn downwardly into the air-fuel distribution chamber 48 through the hollow interior 62 of the stem 40 and the ports 64 of this stem. Such air will be in excess of that required for normal idling. Concurrently with this admission of air in excess of that required for normal idling, a quantity of fuel in excess of that required for idling, will likewise be admitted to the air-fuel distribution chamber 48 inasmuch as such fuel is free to flow from the fuel bypass 44 through the skirt 56 by means of the ports 59. This excess air and fuel flows downwardly from the air-fuel distribution chamber 48, conduit 162, and bore 164 into the carburetor barrel 10. This position of the shut-off valve 42 may be considered a re-fueling position. The air-fuel ratio of this excess air and fuel will be accurately controlled because of the cooperative relationship between the size of the ports 59 and the ports 64. Accordingly, if after deceleration, the engine is again accelerated the engine may undergo a smooth recovery without a flat spot. If instead of again accelerating, the engine is permitted to idle, the introduction of fuel and air in the proper ratio in excess of that required for normal idling will cause the engine to undergo a simulated open throttle condition for a short period of time whereby it will momentarily increase its speed, the air entering the intake manifold will then be enabled to carry a fuel mixture throughout the intake manifold so as to re-wet the intake manifold with fuel. In this manner, the engine may return to normal idling without faltering or stopping Without any appreciable time lag and without requiring any attention whatsoever from the operator of the automotive vehicle.

It should be noted that the regulator member R cannot repeat a shut-off operation until the shut-off valve 42 has depressed the reset valve 104 so as to connect lead time passage 98 with the atmosphere through bore 100 and the lower portion 24 of chamber 28. Upon such occurrence the lead time valve 250 can snap upwardly under the influence of spring 258 so as to close the lower end of passage 244 to the atmosphere. The regulator diaphragm 204 will then be capable of downward flexure when the vacuum Within the lower portion of cavity 210 reaches the necessary magnitude.

It should further be noted that the regulator member R cannot cause the air-fuel shut-off member S to commence a deceleration cycle unless the regulator stem 291 is depressed a sufncient distance to cause the head 228 of the solid idle valve 230 to engage the seat 226. This is true inasmuch as until such time as this head 228 is so seated, the timer chamber 33 will remain in communication with the atmosphere.

Additionally, it should be further noted that the construction of the aforedescribed timer 70 prevents the occurrence of a complete deceleration cycle by the air-fuel shut-oif member S should such a cycle be started under the influence of a light jab of the vehicle operator upon the accelerator pedal. In this regard, should the vehicle operator so jab the accelerator pedal, a momentary increase in the intake manifold vacuum sufficient to cause the regulator stem 201 to be depressed to its lowermost position could take place; Upon such depression of the regulator stem 201, the shutoff valve 42 would be snapped upwardly until its seal ring 58 engaged the lip 46. As noted hereinbefore, such upward movement of the shut-ofl valve 42 would effect a concurrent upward movement of the timer 71 the timer cover 74 being momentarily disposed in its uppermost dotted outline position of FIGURE 2. Assuming the throttle valve 12 to have been returned to an open position after a short interval of time, the shut-off valve 42 will drop prior to the time that the timer cover 74 has been collapsed downwardly. Accordingly, instead of the shut-off valve 42 descending into its charging position of FIGURE 3, it will descend substantially to its normal position of FIGURE 1 before the seal ring 88 of the timer cover 74 engages the seat 90. In this manner the aforedescribed re-fueling operation will be avoided. This is important since the occurrence of such a re-fueling '10 operation at times other than at the conclusion of a decelerating period could create an over-rich fuel condition that would result in improper operation.

It should be especially noted that the operation of the aforedescribed fuel shut-off apparatus for practical purposes is not affected by a change in attitude of an automotive vehicle wherein it is installed. Thus, it will be apparent that as the automotive vehicle moves to a higher altitude, the atmospheric pressure acting upon the bellows 196 is reduced and, accordingly, the bellows tend to elongate. Such elongation serves to reduce the magnitude of the upwardly-directed force exerted by the bellows 196 upon the regulator diaphragm 204. This decrease in the upwardly-directed force of the bellows 196 will be proportional to the increase in altitude. Accordingly, even though the magnitude of the downwardly-acting force effected by the manifold vacuum upon the regulator diaphragm 204 will tend to diminish with an increase in altitude, the supplemental upwardly-acting force exerted thereon will decrease in substantially the same amount.

From the foregoing description, it will be apparent that the fuel shut-off apparatus of the present invention affords major advantages over prior fuel shut-off devices. Such apparatus will permit smooth engine operation under all driving conditions. Additionally, this apparatus will not be adversely affected by a change in the altitude of the automotive vehicle Whereon it is mounted. It may be readily installed upon existing automotive equipment, as Well as upon original automotive equipment, and, when properly installed and adjusted, such apparatus will provide fool-proof operation over a long service life.

Various modifications and changes may be made with respect to the foregoing description without departing from the spirit of the present invention or the ccope of the following claims.

I claim:

1. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator pedal, an intake manifold and idling fuel passage means interconnecting said fuel-supplying device and said intake manifold, comprising: a shutoff member having a body formed with a distribution chamber, said chamber being in communication with said passage means; fluid control means disposed in said distribution chamber and successively movable during a deceleration period between a deceleration position wherein it blocks substantially all flow of fuel through said chamber, a re-fueling position wherein it admits fuel to said distribution chamber in excess of that required for normal idling, and a normal position wherein it admits sufiicient fuel to said distribution chamber to support normal idling; and actuating means operatively connected to said fluid control means so as to urge said fluid control means between said positions responsive to the accelerator pedal setting and rotational speed of said engine, said actuating means moving said fluid control means subst-antially directly from said deceleration position to said normal position when said accelerator pedal is momentarily depressed and raised so as to temporarily increase the magnitude of the intake manifold vacuum to a value approximating that reached during deceleration.

2. Apparatus as set forth in claim 1 wherein said actuating means includes timing means that maintain said fluid control means in said re-fueling position a predetermined period of time before said fluid control means is moved to said normal position, and secondary timing means that render said first-mentioned timing means inoperative until the intake manifold vacuum has been maintained at a value approximating that reached during deceleration for a predetermined time interval.

3. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator pedal, an intake manifold and idling fuel passage means interconnecting said fuel-supplying device and said intake manifold, comprising: a shut-off member having a body formed with a distribution chamber, said chamber being in communication with said passage means; fluid control means disposed in said distribution chamber and successively movable between a deceleration position wherein it blocks substantially all flow of fuel through said chamber, a reueling position wherein it admits fuel to said distribution chamber in excess of that required for normal idling, and a normal position wherein it admits suflicient fuel to said distribution chamber to support normal idling; and actuating means operatively connected to said fluid control means so as to urge said fluid control means between said positions responsive to the accelerator pedal setting and rotational speed of said engine, said actuating means including timing means that maintain said fluid control means in said re-fueling position a predetermined period of time before said fluid control means is movec to said normal position, with said timing means being rendered inoperative when said accelerator pedal is momentarily depressed and raised so as to temporarily increase the magnitude of the intake manifold vacuum to a value approximating that reached during deceleration.

4. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator pedal, an intake manifold and idling fuel passage means interconnecting said fuelsupplying device and said intake manifold, comprising: a shut-ofl" member having a body formed with a distribution chamber, said chamber being in communication with said passage means; plug means operatively disposed in said distribution chamber so as to control the flow of fuel therethrough, said plug means being successively movable during a deceleration period between a deceleration position wherein it blocks substantially all flow of fuel through said chamber, a re-fueling position where it admits fuel to said distribution chamber in excess of that required for normal idling and a normal position wherein it admits sufiicient fuel to said distribution chamber to support normal idling; and actuating means operatively connected to said plug means so as to urge said plug means between said positions responsive to the accelerator pedal setting and rotational. speed of said engine, said actuating means moving said plug means substantially directly from said deceleration position to said normal position when said accelerator pedal is momentarily depressed and raised so as to temporarily increase the magnitude of the intake manifold vacuum to a value approximating that reached during deceleration.

5. Apparatus as set forth in claim 4 wherein said actuating means includes a pressure-responsive wall attached to said plug means and having one of its sides exposed to atmosphere and its opposite side disposed in a sealed chamber connectible to the intake manifold vacuum of said engine during a deceleration period, with communication betweensaid sealed chamber and said intake manifold vacuum being controlled by timing means that maintain said plug in said re-fueling position a predetermined period of time before said plug can be moved to said normal position, with said timing means being rendered inoperative until the intake manifold vacuum has been maintained at a value approximating that reached during deceleration for a predetermined time interval.

' 6. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator pedal, an intake manifold and idling fuel passage means interconnecting said fuel-supplying device and said intake manifold, comprising: a shut-ofl? member having a body formed with a distribution chamber, said chamber being in communication with said passage means; fluid control means disposedin said-distribution chamber and successively movable during a deceleration period between a deceleration position wherein it blocks substantially all flow of fuel through said chamber, a re-fueling position wherein it admits fuel to said distribution chamber in excess of that required for'normal idling, and a normal position wherein it admits sufiicient fuel to said distribution chamber to support normal idling; a pressure-responsive wall disposed in a control chamber formed in said shut-off member, one side of said wall being exposed to the atmosphere and the opposite side of said wall being connected with a timer chamber formed in said shut-off member, said wall being connected to said fluid control means so as to effect said movement of said fluid control means; means temporarily connecting said timer chamber with the intake manifold vacuum of said engine during a deceleration period whereby said wall will be flexed by said vacuum towards said timer chamber and said fluid control means moved to said deceleration position, said wall returning towards its initial position after communication between said timer chamber and intake manifold vacuum is discontinued whereby said fluid control means will be successively moved to said re-fueling position and said normal position; timing means interposed between said timer chamber and the opposite side of said wall, said timing means controlling fluid flow between said timer chamber and said control chamber so as to maintain said fluid control means in said re-fueling position a predetermined period of time before said fluid control means is moved to said normal position; and secondary timing means that render said first-mentioned timing means inoperative until the intake manifold vacuum has been maintained at a valve approximating that reached during a deceleration period for a predetermined time interval whereby said wall may move said fluid control means substantially directly from said deceleration position to said normal position when said accelerator pedal is momentarily depressed and raised so as to temporarily increase the magnitude of the intake manifold vacuum to a value approximating that reached during deceleration.

7. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator pedal, an intake manifold and idling fuel passage means interconnecting said fuel-sup plying device and said intake manifold, comprising: a shut-01f member having a body formed with a distribution chamber, said distribution chamber being in communication with said passage means; plug means operatively disposed in said distribution chamber so as to control the flow of fuel therethrough, said plug means being successively movable during a deceleration period between a deceleration position wherein it blocks substantially all flow of fuel through said chamber, a re-fueling position wherein it admits fuel to said distribution chamber in excess of that required for normal idling and a normal position wherein it admits sufficient fuel to said distribution chamber to support normal idling; a pressure-responsive wall disposed in a control chamber formed in said shut-off member, one side of said wall being exposed to the atmosphere and the opposite side being connected with a timer chamber formed in said shut-off member, said Wall being connected to said plug means so as to effect said movement of said plug means between said positions; means temporarily connecting said timer chamber with the intake manifold vacuum of said engine during a deceleration period whereby said wall will be flexed towards said timer chamber and said plug means moved to said deceleration position, said wall returning towards its initial position after communication between said timer chamher and intake manifold vacuum is discontinued whereby said plug means will be successively moved to said refueling position and said normal position; timing means interposed between said timer chamber and the opposite side of said wall, said timing means controlling fluid flow between said timer chamber and said control chamber so as to maintain said plug means in said refueling position a predetermined period of time before said plug means is moved to said normal position; and secondary timing means that render said first-mentioned timing means inoperative until the intake manifold vacuum has been maintained at a value approximating that reached during a deceleration period for a predetermined time interval whereby said wall may move said plug means substantially directly from said deceleration position to said normal position when said accelerator pedal is momentarily depressed and raised so as to temporarily increase the magnitude of the intake manifold vacuum to a value approximating that reached during deceleration.

8. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator pedal, an intake mani fold and idling fuel passage means interconnecting said fuel-supplying device and said intake manifold, comprising: a shut-01f member formed with a distribution chamber in communication with said passage means, a control chamber, a timer chamber connected with one side of said control chamber by a timer bore, said timer chamber additionally being connected with one side of said control chamber by a timer orifice passage; a pressure responsive wall disposed in said control chamber; plug means operatively disposed in said distribution chamber so as to control the flow of fuel therethrough, said plug means being successively movable during a deceleration period between a deceleration position wherein it blocks substantially all flow of fuel through said distribution chamber, a re-fueling position wherein it admits fuel to said distribution chamber in excess of that required for normal idling, and a normal position wherein it admits suflicient fuel to said distribution chamber to support normal idling, said plug means being operatively connected with said pressure responsive wall; means temporarily connecting said timer chamber with the intake manifold vacuum of said engine during a deceleration period whereby said wall will be flexed towards said timer chamber and said plug means moved to said deceleration position, said wall returning towards its initial position after communication between said timer chamber and intake manifold vacuum is discontinued whereby said plug means will be successively moved to said re-fueling position and said normal position; and a timer disposed in said timer bore and having seal means that cooperate with said bore to block fluid flow therethrough whereby communication between said timer chamber and said one side of said control chamber may take place solely through said timer orifice passage and said plug means will thereby be maintained in said refueling position for a predetermined period of time before said plug means will return to said normal position, said timer incorporating means for rendering said seal means temporarily inelfective until the intake manifold vacuum has been maintained at a value approximating that reached during a deceleration period for a predetermined time interval whereby said wall may move said plug means substantially directly from said deceleration position to said normal position when said accelerator pedal is momentarily depressed and raised so as to temporarily increase the magnitude of the intake manifold vacuum to a value approximating that reached during deceleration.

9. Apparatus as set forth in claim 8 wherein said timer includes a hollow fluid-receiving body and a cover telescopically slidably carried by said body for longitudinal extension relative to said timer bore, with said seal being formed on said cover, said shut-01f member also having means constantly biasing said cover towards a non-extended position relative to said body, the fluid entering said timer as said wall is flexed towards said timer chamber temporarily resisting movement of said cover towards a non-extended position whereby said seal means will be rendered temporarily ineffective.

10. Apparatus for controlling the admission of fuel to an internal combustion engine having a fuel-supplying device operated by an accelerator, an intake manifold and idling fuel passage means interconnecting said fuel-supplying device and said intake manifold, comprising: a fuel T4 shut-off valve that blocks flow of fuel through said idling passage means during deceleration, admits more fuel than that required for normal idling into said idling passage means after a deceleration period and then admits sufiicient fuel to support normal idling; and actuating means for said valve that automatically renders it ineffective to admit more fuel than that required for normal idling unless said engine undergoes a complete deceleration period.

11. In internal combustion engine fuel shut-off apparatus having a shut-off member that blocks the flow of fuel into said engine during deceleration, with the flow of fuel to said engine being controlled by an accelerator pedal, the combination of: a regulator formed with a diaphragm chamber that is intersected by a stem bore; a diaphragm in said diaphragm chamber that is capable of flexure into a control position; a stem in said stem bore operatively connected to said diaphragm for movement thereby; biasing means on said regulator constantly urging said diaphragm away from said control position; regulator vacuum passage means intersecting said stem bore; a bypass conduit connecting said diaphragm chamber and said regulator vacuum passage; a land on said stem normally blocking communication between said regulator vacuum passage and said diaphragm chamber; means operatively connecting said stem and said shut-off member so as to cause said shut-off member to block the flow of fuel into said engine when said diaphragm has been flexed into said control position, said diaphragm flexing towards said control position when the intake manifold vacuum exceeds a predetermined magnitude, said diaphragm flexing slowly until said land uncovers said regulator vacuum passage whereupon said diaphragm will immediately snap into said control position. i

12. In internal combustion engine fuel shut-off apparatus having a shut-off member that blocks the flow of fuel into said engine during deceleration, with the flow of fuel to said engine being controlled by an accelerator pedal, the composition of: a regulator formed with a diaphragm chamber that is intersected by a stem bore; a diaphragm in said diaphragm chamber that is capable of flexure into a control position; a stem in said stem bore operatively connected to said diaphragm for movement thereby; biasing means on said regulator constantly urging said diaphragm away from said control position; regulator vacuum passage means intersecting said stem bore; a bypass conduit connecting said diaphragm chamber and said regulator vacuum passage; a land on said stem normally blocking communication between said regulator vacuum passage and said diaphragm chamber; means operatively connecting said stem and said shut-off member so as to cause said shut-off member to block the flow of fuel into said engine when said diaphragm is flexed into said control position, said diaphragm flexing towards said control position when the intake manifold vacuum exceeds a predetermined magnitude, said diaphragm flexing slowly until said land uncovers said regulator vacuum passage whereupon said diaphragm will immediately snap into said control position; additional conduit means connecting the intake manifold and said fuel shut-0E member; valve means operated by movement of said stem that normally blocks flow through said additional conduit means, with said valve means being opened when said diaphragm flexes into said control position; solid idle passage means connecting said additional conduit means with the atmosphere; and solid idle valve means normally permitting communication between said additional conduit means and the atmosphere, said solid idle Valve means being closed only by a complete movement of said diaphragm into said control position.

13. Fuel shut-off apparatus for controlling the flow of fuel to an internal combustion engine having an intake manifold, comprising: a shut-off valve movable between a normal open position and a shut-01f position wherein it blocks flow of fuel into said intake manifold during deceleration; a regulator that actuatessaid shut-01f valve and is formed with a diaphragm chamber that is in communication with the intake manifold vacuum of said engine and is also in communication with passage means connected with the atmosphere; a diaphragm in said diaphragm chamber that is capable of flexure towards a position that effects movement of said shut-off valve into its shut-off position when the magnitude of said intake manifold vacuum reaches a predetermined value and said diaphragm chamber is cut off from communication with the atmosphere; valve means disposed in said passage means to control fluid flow therethrough, said valve means normally blocking fluid flow therethrough; means operatively connected to said valve means that moves said valve means to an open position when said diaphragm elfects movement of said shut-oft valve towards its shutofi position; and reset means operatively connected with said shutoff valve that eiiect return movement of said valve means to its normal position only when said shutolf valve has substantially completed movement into its shut-01f position.

14. Fuel shut-otf apparatus as set forth in claim 13 wherein said reset means includes an element disposed in the path of said shut-off valve so as to be physically engaged thereby as said shut-oil valve completes its movement into a shut-off position.

15. Fuel shut-off apparatus as set forth in claim 13 wherein said reset means includes a reset valve formed with a stem disposed in the path of said shut-off valve and spring means biasing said reset valve towards a closed position relative to said passage means, with said shutoff valve engaging said stem so as to open said reset valve when said shut-oil valve moves into its shut-off position.

16. Fuel shut-ofi apparatus for controlling the flow of fuel to an internal combustion engine having an intake manifold, comprising: a shut-off valve movable between a normal open position and a shut-off position wherein it blocks flow of fuel into said intake manifold during deceleration; a regulator that actuates said shut-off valve and is formed with a diaphragm chamber that is in communication with the intake manifold vacuum of said engine and is also in communication with passage means connected with the atmosphere; a diaphragm in said diaphragm chamber that is capable of flexure towards a position that eifects movement of said shut-01f valve into its shut-off position when the magnitude of said intake manifold vacuum reaches a predetermined value and said diaphragm chamber is cut off from communication with the atmosphere; and means that control fluid flow through said passage means, said means normally blocking said passage means until said diaphragm has effected movement of said shut-0E valve towards a shut-0E position, whereafter said passage means will remain open until said shut-otf valve has substantially completed movement into its shut-oft position, said means then again blocking said passage.

17. Fuel shut-oif apparatus as set forth in claim 16 wherein said last-mentioned means includes an element disposed in the path of said shut-01f valve so as to be physically engaged thereby as said shut-ofi valve completes its movement into a shut-off position.

18. Fuel shut-01f apparatus as set forth in claim 16 wherein said last-mentioned means includes a reset valve formed with a stem disposed in the path of said shutofI valve and spring means biasing said reset valve towards a closed position relative to said passage means, with said shut-01f valve engaging said stem so as to open said reset valve when said shut-off valve moves into its shutoff position.

19. In an internal combustion engine fuel shut-off apparatus for use with an engine having an intake manifold and with said apparatus having a shut-ofl? member that blocks the flow of fuel into said engine during deceleration, the combination of: a regulator formed with a diaphragm chamber that is in communication with the intake manifold vacuum of said engine; a diaphragm in said chamber that is capable of flexure into a shut-0E position when the magnitude of said vacuum reaches a predetermined value; means-operatively connecting said diaphragm with said shut-01f member whereby said diaphragm will actuate said shut-0E member; and a sealed altitude compensating bellows on said regulator that constantly biases said diaphragm in a direction away from its shut-otf position with a force that decreases proportional with an increase in altitude.

References Cited in the file of this patent UNiTED STATES PATENTS 2,269,496 Vanderpoel et al. Jan. 13, 1942 2,466,090 Fageol Apr. 5, 1949 2,284,726 Dietrich Feb. 25, 1958 2,868,182 Cornelius Jan. 13, 1959- 2,875,741 Leibing Mar. 3, 1959 2,877,998 Cornelius Mar. 17, 1959 2,879,756 Cornelius Mar. 31, 1959