US3626919A - Fail-safe throttle control - Google Patents

Fail-safe throttle control Download PDF

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US3626919A
US3626919A US88450A US3626919DA US3626919A US 3626919 A US3626919 A US 3626919A US 88450 A US88450 A US 88450A US 3626919D A US3626919D A US 3626919DA US 3626919 A US3626919 A US 3626919A
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fail
control mechanism
safe
throttle
throttle control
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Charles W Macmillan
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D17/00—Controlling engines by cutting out individual cylinders; Rendering engines inoperative or idling
    • F02D17/04—Controlling engines by cutting out individual cylinders; Rendering engines inoperative or idling rendering engines inoperative or idling, e.g. caused by abnormal conditions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K26/00—Arrangement or mounting of propulsion-unit control devices in vehicles
    • B60K26/04—Arrangement or mounting of propulsion-unit control devices in vehicles of means connecting initiating means or elements to propulsion unit
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K28/00—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
    • F02D9/02—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits concerning induction conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L2710/00—Control of valve gear, speed or power
    • F01L2710/006—Safety devices therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B1/00—Engines characterised by fuel-air mixture compression
    • F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
    • F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B3/00—Engines characterised by air compression and subsequent fuel addition
    • F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
    • F02D9/02—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits concerning induction conduits
    • F02D2009/0201—Arrangements; Control features; Details thereof
    • F02D2009/0264—Arrangements; Control features; Details thereof in which movement is transmitted through a spring
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
    • F02D9/02—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits concerning induction conduits
    • F02D2009/0201—Arrangements; Control features; Details thereof
    • F02D2009/0271—Arrangements; Control features; Details thereof with means for closing the throttle other than throttle closing springs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
    • F02D9/02—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits concerning induction conduits
    • F02D2009/0201—Arrangements; Control features; Details thereof
    • F02D2009/0277—Fail-safe mechanisms, e.g. with limp-home feature, to close throttle if actuator fails, or if control cable sticks or breaks
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2700/00—Mechanical control of speed or power of a single cylinder piston engine
    • F02D2700/02—Controlling by changing the air or fuel supply
    • F02D2700/0217—Controlling by changing the air or fuel supply for mixture compressing engines using liquid fuel
    • F02D2700/0225—Control of air or mixture supply
    • F02D2700/0228—Engines without compressor
    • F02D2700/023—Engines without compressor by means of one throttle device

Definitions

  • the present invention not only provides protection against a broken throttle return spring, but in addition senses any deviation from normal operation of the accelerator linkage due to any of the causes heretofore mentioned and provides for suitably disabling the engine.
  • engine speed is maintained at idle which is important when the device is applied to large motor vehicles using power steering and power brakes where stopping the engine would cause dangerously difficult steering and braking.
  • FIG. 1 shows the fail-safe throttle mechanism utilizing a push rod system with a vacuum valve integral with the push rod linkage used to control a vacuum power cylinder to return the carburetor to idle;
  • FIG. 2 shows the fail-safe throttle mechanism utilizing a push rod system with two valves operating in concert to control the vacuum power cylinder;
  • FIG. 3 shows schematically the fail-safe throttle system utilizing a push rod system with the disabling electrical point system integral with the push rod linkage
  • FIG. 4 shows schematically the system of FIG. 3 which is further adapted to using a pull cable connection to the accelerator pedal linkage;
  • FIG. 5 shows the fail-safe throttle system utilizing a push rod system with the disabling electrical point system pivotally mounted
  • FIG. 6 shows the system adapted to using a pull cable connection to the accelerator pedal linkage with the disabling electrical point system pivotally mounted
  • FIG. 7 shows still another embodiment wherein two switches and a relay are substantially substituted for the vacuum valve system of FIG. 2 to render the system fail safe.
  • FIG. 7A shows the use of two switches wired in parallel in the embodiment shown in FIG. 7 to eliminate the need for a relay
  • FIG. 8 shows another embodimentwherein a solenoid is used in conjunction with the two switches of FIG. 7 to return the throttle to idle position in case of failure;
  • FIG. 9 shows a further embodiment wherein a solenoid is used in conjunction with the single integral switch of FIGS. 3, 4, 5 or 6 to return the throttle to idle position in case of failure;
  • FIG. 10 shows a still further embodiment wherein hydraulic pressure is used to return the carburetor to idle.
  • FIG. I there is shown a cross-sectional view of floorboard 15 of a vehicle to which an accelerator pedal 10 is pivotally attached at its lower end which is not shown.
  • a push rod 12 is pivotally mounted to the accelerator pedal 10 in any standard manner and as normally used in motor vehicles, and extends slidably through cylindrical housing 20 and isrigidly attached by threading or other means to valve 1 l.
  • the vacuum valve assembly 13 has a generally cylindrical housing 14 open at one end to reveal a cylindrical bore adapted to receive the valve 11 and closed at the other end with a solid wall having an ofi'standing cylindrical rod 16 extending concentrically along its axis.
  • the rod end 17 may be flattened to form a rectangular cross section link end and is suitably perforated for apertures 18 and I9.
  • other ways of accomplishing this connection will be apparent.
  • valve 11 is slidably fitted into the open bore of the housing 14 and thereafter the axially perforated cover 20 is attached to the housing by any convenient means.
  • valve 11 is suitably reduced to receive surrounding spring 21 which is disposed between the valve 11 and the bottom of the bore of housing 14 under compression to urge valve 11 upwardly toward the cover 20.
  • THe cover 20 includes an axially disposed tubular extension of reduced diameter slotted as at 28 and 29 as shown which extends upwardly through the floorboard 15 and dust seal 22, the tubular extension being arranged to slidably support rod 12 to which the pedal 10 is attached as hereinbefore described.
  • the housing is perforated as shown and provided with nipples 23 and 24 and adapted to receive the conduits shown attached thereto, the purpose of which will be understood as the description progresses.
  • the valve 11 is provided with an annular groove about its major diameter in such a manner that when the valve body is urged to its uppermost position by spring 21, the conduits connected to nipples 23 and 24 can communicate with the groove 25 as is well known in spool valve construction.
  • the accelerator push rod 12 is suitably drilled at 26 to allow pin 27 to be press-titted thereinto, the pin extending through the slots 28 and 29 arranged to act as a stop against the floor 15 when the spring 21 and return spring 32 urge the rod 12 upwardly.
  • the lower end of the housing 14 is supported by a link 30 which is pivotally attached thereto at 18 by a pin bolt or other suitable means, and at its other end in a similar manner is suitably and pivotally attached to some portion of the vehicle with the link being suitably perforated generally medially of its length at 31 to receive one end of the throttle return spring 32, and the other end thereof being attached firmly to a fixed anchorage either on the firewall or the engine.
  • a push rod construction Disposed between the end of the housing 14 and throttle plate lever 33 carried by the carburetor is a push rod construction incorporating a two-way yield device constructed as follows.
  • a tubular casing 35 having a suitable partition 35' for a purpose to be described is positioned between the end of housing 14 and the throttle plate lever 33 by rods 34 and 43, respectively.
  • Rod 34 which includes a rigid disc 37 afi'ixed to one end and arranged to be positioned in the casing on one side of the partition 35 has its free end arranged to extend through apertured cover 36 and thereafter be secured to the portion 16 which offstands axially of the housing 14, as shown.
  • a coil spring 38 is provided between the disc 37 and the cover 36 for a purpose that will become apparent later.
  • the two-way yield device allows rods 34 and 43 to separate if a force greater than the compressive spring force of spring 38 is applied and allows said rods to come together if a force greater than the compressive spring force of spring 41 is applied.
  • the pivotal lever 33 communicates directly with throttle plate 56 through rod 57.
  • Idle adjusting screw 58 bears against stop 59 which allows positioning of the throttle plate and therefor adjustment of the idle speed.
  • Lever 60 communicates directly with choke valve 61 positioned in the throat of the carburetor and now shown in its open position, this element being controlled to open through lever 62 and push rod 63 by thermostatic coil spring 64 shown here only schematically.
  • the lever 60 communicates with fast idle cam 65 through push rod 66.
  • Fast idle screw 67 bears against fast idle cam 65 when the throttle valve 56 is closed or partially closed during warm up, thus opening the throttle valve 56 to a greater or lesser degree depending on the choke position, therefore preventing the engine from stalling.
  • throttle return spring 32 is strong enough to overcome the compressive spring force of spring 21 thus urging vacuum assembly 13 toward the firewall 15 of the vehicle or other positive stop means that is provided therefor.
  • the ,stop pin 27 being then in contact with firewall 15 or stop means as explained causing push rod 12 to resist the motion of vacuum assembly 13 forcing valve body 11 to its lowermost position and causing the upper land of the valve (as shown in FIG. 1) to block communication between the flexible tubes 55 and 55', respectively.
  • spring 21 remains compressed due to the restraining force of throttle return spring 32, thus maintaining valve 11 in its lowennost position, while at the same time, the forward motion is transmitted through housing 14, push rod 34, disc 37, housing 35, rod 43 to the throttle lever 33, thus opening the throttle.
  • valve 1 1 will block communication between the vacuum chamber 45 and the intake manifold vacuum and that no vacuum will be applied to the idle return vacuum power cylinder. If however, the driver removes his foot from the accelerator pedal 10 and the throttle does not return to its idle rest position, spring 21 will be released forcing valve 11 upwardly toward cover 20, at which time the annular groove 25 will provide communication between conduits 55 and 55', thus applying vacuum to the idle return vacuum power cylinder 45 and returning the engine to idle.
  • the throttle may be required to be adjusted to different openings depending upon the characteristics of a specific carburetor engine, etc.
  • the purpose of the two-way yield device can now be readily seen. As the idle screw 58 or fast idle screw 67 are adjusted, rod 43 moves axially as lever 33 moves. Were it not for the yield device, the vacuum valve assembly would move away from the firewall releasing pressure on spring 21 and applying vacuum to the power cylinder 45. With the new yield device described herein, as rod 43 moves, it causes spring 38 to be compressed slightly without disturbing the balance of the remainder of the system. It is required in the ap plication of this system that spring 32 be able to overcome the spring force of spring 38 and spring 21.
  • the purpose of the second spring 41 provided in housing 35 is to allow the vacuum power cylinder 45 to actuate the throttle lever and return it to an idle position should the linkage between housing link 35 and the accelerator pedal become bound or frozen.
  • FIG. 2 there is shown an upper accelerator pedal plate 10 pivotally mounted at its lower end to lower accelerator plate 68.
  • the upper end of pedal plate 10 is suitably hooked at to communicate with a tang 69A carried by plate 68 such that it allows small angular motion between the two plates.
  • Lower plate 68 is suitably bored to receive spring 69 which is under a compressive force urging plates 10 and 68 apart, these plates, however, being restrained from separation by tang 69A and hook 70.
  • Rigidly mounted within a suitable opening in plate 68 is vacuum valve 71, its actuating pin 71' being located so as to be actuated when plates and 68 are pressed together.
  • the assembly is pivotally mounted to the fioorboard by pivot pin 72 and a bracket, not shown.
  • Push rod 12 is pivotally mounted at one end to lower plate 69 in a suitably formed socket 73 and passes slidably through the firewall.
  • the other end of rod 12 is bent and extends through a suitable perforation at one terminal end of link 74 retained by any suitable means, not shown.
  • the link 74 is pivotally mounted at its other end to a bracket firmly affixed to the frame such that the link is substantially perpendicular to rod 12 and as explained earlier, the link 74 is associated with the firewall by means of a return spring 32.
  • a vacuum valve 75 Mounted on firewall 15 or other fixed and rigid member is a vacuum valve 75 with an actuating arm means 76 that is pivotally or resiliently mounted so as to communicate with the actuating pin of valve 75.
  • actuating arm means 76 Mounted on rod 12 is an adjustable valve actuating means 76', the purpose of which should be apparent without further discourse.
  • vacuum power cylinder 45 which is the same in construction as described in the first embodiment of this invention.
  • valve actuator 76' In its at-rest position, spring 32 urges the carburetor throttle plate arm against the idle stop as explained earlier.
  • the adjustable valve actuator 76' is initially adjusted so that the valve actuating arm 76 may close the valve. It is, of course, understood that there is no foot pressure now being applied to the accelerator pedal upper plate 10 and therefore spring 69 urges plates 10 and 68 apart allowing valve 71 to remain open. However, when foot pressure is applied to the accelerator pedal upper plate 10, it is forced towards plate 68 against the spring pressure of the throttle return spring 32 and spring 69. Thus, valve 71 is actuated and now closes. As push rod 12 is urged forward, valve actuator 76' moves forward allowing valve 75 to open.
  • valves 71 and 75 act in concert to maintain a closed vacuum circuit to vacuum power cylinder 45 as long as communication between the accelerator pedal and carburetor is normal and when there is pressure on the accelerator pedal and the system is in other than an idle condition. Should the linkage bind or the spring 32 break, and the operator removes his foot from pedal 10, valves 71 and 75 will both be in an open condition applying vacuum to vacuum power cylinder 45, returning the throttle to an idle condition.
  • FIG. 3 shows such an embodiment utilizing a set of contact points which are integral with the accelerator push rod to sense throttle linkage failure and stop the engine.
  • Push rod 12 is pivotally mounted to accelerator pedal 10 in any standard manner as normally used in motor vehicles and extends through cylindrical upper housing 77 into spring retainer 78 and insulated contact support 79, both of which are pinned or otherwise rigidly affixed to rod 12.
  • the contact switch assembly generally indicated as 80, has a substantially cylindrical housing 81 open at one end with a means 16 extending from its lower end along its axis, the means being arranged to form a rectangular link end and suitably perforated to form apertures 18 and 19 as hereinbefore described in the first embodiment.
  • the cover 20 for the housing includes the support for rod 12, and the similarity of these elements will be appreciated from a comparison of FIGS. 1 and 3.
  • the end of insulated contact support 79 positioned in the housing is concentrically drilled and/or tapped to receive contact element 83, and attached thereto by any convenient means is a conductor wire 84 which passes through perforation in the end of housing 81 this being suitably bushed to prevent chafing.
  • Housing 81 is suitably drilled and tapped in its bottom concentric with its inner bore to receive the metal contact element 86 with the housing 81 being grounded to the electrical ground of the vehicle.
  • Spring 21, as shown, is disposed between the bottom of the housing 81 and the spring retainer 78 while the push rod 12 is suitably drilled to allow the pin 27 to be arranged as a stop and for the purpose explained earlier.
  • the lower end of the housing 81 is pivotally supported by link 30 and spring 32 which is associated therewith and operates in the same manner as explained in connection with FIG. 1.
  • a push rod incorporating a one-way yield device constructed as follows.
  • Rod 34 is secured at one end to housing 81, as shown at 19, and its opposite end includes a disc 37 which is positioned in casing 89, the casing being closed with a perforated cover through which the rod 34 is arranged to extend.
  • a spring 38 is disposed within housing 86 under a compressive force between disc 37 and cover 36 so as to normally hold rods 34 and 87, the latter being affixed to the throttle plate in fixed alignment, disc 37 being a relatively close sliding fit in the bore of housing 86, and rod 34 being a substantially close sliding fit in the concentric perforation in cover 36.
  • the one-way yield device is substantially one-half of the two-way yield device described earlier and is required to allow adjustment of the carburetor as explained herein before.
  • Contact means 83 and 86 form the ground connection for the ignition system.
  • the throttle return spring 32 has sufficient strength to overcome the compressive spring force of spring 21 and spring 38 thus urging housing 81 toward the firewall l5, and thus causing push rod 12, spring retainer 78, insulated contact support 79 and contact element 83 to resist the motion of housing 81 bringing the contact means 83 and 86, respectively, together and completing the ignition ground.
  • spring 21 will be released and force spring retainer 78, insulated contact support 79 and contact 83 away from the bottom of housing 81, thus separating the contacts and effectively turning off the ignition.
  • FIG. 4 there is shown another embodiment of this invention which utilizes a pull cable to close the fail-safe switch.
  • the accelerator pedal 10 is pivotally mounted on arm 91 which, in turn, is pivotally mounted on bracket 92 attached, for example, to the firewall.
  • a cable 93 passes through a suitable conical perforation in the upper end of arm 91 and is secured in tension by a standard compression ball.
  • link 99 is pivotally mounted on a support 100 which is rigidly attached to the frame.
  • the switch housing is pivotally attached to the upper end of link 99 and slidably supported in bushing 101, tube 96 extending through dust shield 102 and through the firewall.
  • rod 34 of the one-way yield device constructed and used as hereinbefore described.
  • throttle return spring 32 is attached to a suitable perforation in link 99 and finnly attached at the other end to a fixed anchorage.
  • the spring force of spring 32 must be adequate to overcome the spring force of spring 103 and spring 38 for the reasons earlier described. It is evident from the discussion of the previous embodiments that under all normal conditions contacts 97 and 98 are in contact maintaining a proper electrical ground for the ignition to operate. If the throttle fails and remains in an open condition when the operator removes his foot from the accelerator pedal, spring 103 opens contacts 97 and 98 and the engine stops.
  • FIG. 5 there is shown a further embodiment of this invention in which the contacts are pivotally mounted instead of axially mounted.
  • the grounded contact arm 104 is pivotally mounted so as to rotate about shaft 105 which is rigidly affixed to the frame, and the insulated contact arm 108 is pivotally mounted at the same pivot.
  • Contact means 107 is rigidly attached by riveting to an apertured ear extending at right angle from arm 104 and in a substantially radial direction from pivot 105.
  • Contact element 108 is mounted by means of insulated washers to an apertured ear extending at right angles to arm 106 so that the pair of contacts are in direct alignment with each other.
  • ear 109 with spring support pin 110 at its center extends from arm 104
  • ear 111 with spring support pin 117 at its center extends from arm 106.
  • Spring means 113 is disposed between ear 109 and 111 to hold the contact elements I07 and 108 apart. Extending also at right angles from arm 104 is an arm 114 which is suitably threaded to receive a stop screw 115 which is provided with a lock nut 116. It will be noted in this embodiment that the stop screw 115 bears against a stop 117 which is rigidly attached to the firewall 15.
  • Arm 106 is extended downwardly to a perforated terminal end to which one end of the spring 32, the throttle return spring, is attached, while the other end of the spring is connected to a fixed anchorage.
  • the sleeve 118 is pivotally connected to arm 106 by pivot bolt means 119 and is arranged to extend through a dust shield in the firewall thereby providing a slidable support for push rod 12 which, as shown, is pivotally affixed to the lower terminal end of arm 104 and extends upwardly so as to be pivotally affixed to the accelerator pedal 10.
  • Arm 106 is suitably perforated to receive the bent end of rod 34 which connects through the one-way yield device to the throttle plate lever 33 as hereinbefore described.
  • the functions are the same as those in FIG. 3, wherein the switch assembly is an integral part of the push rod assembly. It is believed that from the foregoing it will be now appreciated that the throttle return spring 32 is sufficiently adequate to overcome the force of one-way yield spring 38 and spring 113, thus urging arm 106 and contact 108 against contact 107, while simultaneously forcing arm 104 and stop screw 115 against stop 117.
  • the application of pressure on the accelerator pedal 10 transmits the forwardly directed force through arm 104, contact elements 107 and 108, arm 106 into rod 34, rod 87, to the throttle plate lever 33, thereby maintaining constant contact to properly ground the ignition system. It is evident that should the throttle stick open or spring 32 break and pedal pressure is removed, spring 1 13 will urge said contact members apart, causing the ignition system to be disabled.
  • FIG. 6 shows another embodiment of this invention using a pull cable with pivoted contacts. From the foregoing construction and description in FIGS. 4 and 5, the construction and operation of this embodiment should be clear to those skilled in the art.
  • the pivotal point assembly has been reversed so that pulling closes the points and a reversing link is used to achieve a pushing motion to operate the carburetor throttle lever.
  • This embodiment combines elements from FIGS. 4 and 5 to perform the same functions as previously described.
  • switch 120 is affixed to the lower pedal 68, and a switch 121 which is rigidly attached to the firewall 15.
  • Switch 120 replaces valve 71 of FIG. 2 and switch 121 replaces valve 75 in that same view.
  • These switches perform substantially the same function to switch electrical energy to relay 122 to stop the engine in case of throttle failure.
  • FIG. 7 also shows no yield device, the removal of which may be accomplished by arranging switch 121 to have sufficient overtravel to be actuated just before maximum fast idle when the pedal is relaxed and allowing the linkage to return to slowest idle position when fast idle is not required. It should be clear that this principle can be applied to all of the other embodiments shown.
  • FIG. 7A An alternate approach is shown in which switches 120 and 121 are arranged in parallel with each other, the pair being placed in series with the ignition circuit eliminating the need for relay 122 and opening the ignition circuit to stop the engine in the case of throttle failure.
  • FIG. 8 is a further embodiment which illustrates how the return to idle operation can be accomplished electrically.
  • the solenoid means 123 replaces the vacuum power unit 45 of FIG. 2.
  • the precise actions of the embodiment of F IG, 2 are achieved electrically.
  • FIG. 9 illustrates the same action by combining the single contact switch of the embodiment shown in FIG. 3 with the solenoid means 123 of FIG. 8.
  • hydraulic power is available within motor vehicles which have power steering and therefore high-pressure hydraulic fluid may be used to return the carburetor to idle.
  • a hydraulic power cylinder 124 replaces the vacuum power cylinder 45 of FIG. 2.
  • the vacuum valves 71 and 75 of FIG. 2 With hydraulic valves (not shown), will provide the same valving action.
  • By replacing the vacuum lines with hydraulic lines and connecting the system to the high-pressure line of the power steering pump improper communication between the accelerator pedal and the carburetor will allow both valves to open, applying high pressure oil to the hydraulic power cylinder 124, to thereby return the carburetor to idle.
  • throttle plate lever means may represent the throttle control lever in any of its forms including that for the fuel control rack on diesel engines.
  • a fail-safe throttle control mechanism for internal combustion engine carburetors including a carburetor mounted on a motor vehicle comprising throttle plate lever means associated with the carburetor, means carried by said throttle plate lever means extending to an accelerator pedal, said lastnamed means further including means for sensing failure of the accelerator pedal to return to a normal condition upon an attempt to decelerate and reacting to such improper communication of operation of the released accelerator pedal to said throttle plate lever means, and said reacting means being so disposed in the mechanism for immediately rendering the engine operation safe by returning the throttle plate lever to an idle position.
  • a fail-safe throttle control mechanism as claimed in claim I wherein the means carried by said throttle plate lever means extending to the accelerator pedal is push operated.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • General Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)
US88450A 1970-11-10 1970-11-10 Fail-safe throttle control Expired - Lifetime US3626919A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US8845070A 1970-11-10 1970-11-10

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US3626919A true US3626919A (en) 1971-12-14

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US88450A Expired - Lifetime US3626919A (en) 1970-11-10 1970-11-10 Fail-safe throttle control

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US (1) US3626919A (enExample)
CA (1) CA953171A (enExample)
DE (1) DE2155681A1 (enExample)
FR (1) FR2113736A5 (enExample)
GB (1) GB1367152A (enExample)
IT (1) IT940384B (enExample)
SE (1) SE372059B (enExample)

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3698372A (en) * 1971-06-08 1972-10-17 Holley Carburetor Co Throttle return spring redundancy system
US3731663A (en) * 1971-01-08 1973-05-08 Hollins J R Vehicle engine fuel control accelerator override
US3734230A (en) * 1970-12-17 1973-05-22 Y Tanaka Emergency stop switch means for a mobilized sledge or the like
US3738347A (en) * 1972-02-14 1973-06-12 Gen Motors Corp Throttle pedal controlled pneumatically operated throttle override
US3742928A (en) * 1972-05-30 1973-07-03 Zeal Corp Safety throttle for internal combustion engines
US3757758A (en) * 1972-07-24 1973-09-11 Gen Motors Corp Throttle pedal actuated throttle return
US3760786A (en) * 1972-12-01 1973-09-25 Colt Ind Operating Corp Redundant throttle return system
US3789938A (en) * 1972-04-24 1974-02-05 Artic Ets Inc Automatic shut-off switch
US3791366A (en) * 1970-11-10 1974-02-12 Millan C Mac Fail-safe throttle control
US3798402A (en) * 1972-04-19 1974-03-19 A Raab Safety switch and control system for vehicles
US3802406A (en) * 1971-12-28 1974-04-09 Sibe Fuel feed devices for internal combustion engines
US3830213A (en) * 1972-02-24 1974-08-20 Colt Ind Operating Corp Throttle return spring redundancy system
US3838674A (en) * 1970-12-15 1974-10-01 Peugeot & Renault Safety device for a carburettor control means
US3861377A (en) * 1973-01-12 1975-01-21 Volkswagenwerk Ag Throttle valve arrangement for a combustion engine
US3881461A (en) * 1973-08-03 1975-05-06 Stanislaw F Filip Automatic power cut-off device for vehicles
US3903864A (en) * 1972-05-31 1975-09-09 Peugeot Control device in particular for a carburetter throttle
US3924596A (en) * 1973-01-12 1975-12-09 Volkswagenwerk Ag Fail-safe throttle for an internal combustion engine
US3927657A (en) * 1973-04-05 1975-12-23 Sibe Throttle return systems for carburettors
US3943907A (en) * 1973-10-19 1976-03-16 Societe Industrielle De Brevets Et D'etudes S.I.B.E. Throttle return systems for carburettors
US3952827A (en) * 1974-11-07 1976-04-27 Trw Inc. Acceleration control system
US3954151A (en) * 1974-04-29 1976-05-04 Klf Patents, Inventions, And Marketing Corporation Limited Safety control for mobile vehicles
US4122819A (en) * 1976-09-22 1978-10-31 Hyster Company Fuel supply control and carburetor linkage mechanism
WO1981000696A1 (en) * 1979-09-14 1981-03-19 Towmotor Corp Vehicle brake and engine interlock
US4295540A (en) * 1979-09-14 1981-10-20 Towmotor Corporation Vehicle brake and engine interlock
US4336778A (en) * 1980-02-29 1982-06-29 Delta Systems, Inc. Safety limiter for engine speed
US5193640A (en) * 1991-01-17 1993-03-16 Lee Hae Seung Vehicle safety system for driver pedal misapplication
US5448029A (en) * 1992-11-20 1995-09-05 Regie Nationale Des Usines Renault Idling engine clutch release control device of an automatic transmission
US5653207A (en) * 1996-01-31 1997-08-05 James Clifford Sterling Diesel engine emergency shutoff device
US20050194064A1 (en) * 2004-02-17 2005-09-08 Guofang Cao Configurations and designs for stump grinding teeth and corresponding holding brackets
US20060201684A1 (en) * 2005-03-10 2006-09-14 Throttle Control Tech Inc. Throttle limiting control box for snubbing units in conjunction with service or drilling rigs
US20100116246A1 (en) * 2008-11-11 2010-05-13 Mitsubishi Electric Corporation Throttle body for internal combustion engine
US20100315072A1 (en) * 2008-02-28 2010-12-16 Arno Marto Linear Sensor
CN102152740A (zh) * 2010-02-11 2011-08-17 中集车辆（集团）有限公司 油门加速装置及安装有该油门加速装置的混凝土搅拌运输车
US8322685B1 (en) * 2010-07-23 2012-12-04 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Non-collinear valve actuator
US8939219B2 (en) 2011-05-05 2015-01-27 Snubco Manufacturing Inc. System and method for monitoring and controlling snubbing slips
US9074535B1 (en) 2013-12-19 2015-07-07 Kohler Co. Integrated engine control apparatus and method of operating same
US9261030B2 (en) 2013-05-20 2016-02-16 Kohler Co. Automatic fuel shutoff
CN111502826A (zh) * 2020-04-22 2020-08-07 合肥康尔信电力系统有限公司 一种柴油发电机用可拆卸固定架装置及工作方法

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US1097778A (en) * 1911-05-13 1914-05-26 Packard Motor Car Co Motor-vehicle.
US1833908A (en) * 1929-03-18 1931-12-01 Maybachmotorenbau Gmbh Controlling device for carburetors of internal combustion engines
US2067332A (en) * 1936-05-06 1937-01-12 Numer Harold Bolinger Control for a safer operation of motor vehicles
US2148729A (en) * 1937-06-24 1939-02-28 Carter Carburetor Corp Carburetor throttle control
US2188704A (en) * 1938-02-12 1940-01-30 Gen Motors Corp Engine throttle governor
US2260576A (en) * 1938-04-14 1941-10-28 Maybach Motorenbau Gmbh Device for safeguarding internal combustion engines against excessive speed and lubrication failure
US2313011A (en) * 1938-06-27 1943-03-02 Duwe August Apparatus for controlling the speed of revolution of machines
US2455573A (en) * 1945-07-07 1948-12-07 Bendix Aviat Corp Signal mechanism
US2517501A (en) * 1947-02-04 1950-08-01 Solex S A R L Soc Overspeed prevention device for internal-combustion engines
FR1052320A (fr) * 1951-03-13 1954-01-22 Dispositif de manoeuvre de l'organe d'étranglement qui détermine la puissance d'un moteur à combustion, plus particulièrement applicable à la conduite du moteur d'un véhicule automobile
US2678033A (en) * 1951-01-31 1954-05-11 Sulzer Ag Internal-combustion engine exhaust control system
US2793706A (en) * 1955-06-20 1957-05-28 Edward R Moreland Safety control for automobiles
US2836669A (en) * 1955-05-09 1958-05-27 Gaylord Prod Inc Electric switch for linkages
US2897806A (en) * 1957-03-05 1959-08-04 Landrum Porter Vacuum responsive throttle control for internal combustion engines
AU200061A (en) * 1960-03-09 1963-03-07 T. M. M. Research ) Limited Improvements relating tothe treatment of textile fibrous materials
US3121214A (en) * 1961-09-08 1964-02-11 Charles A Frederick Signaling system for indicating improper operation of an accelerator pedal
US3171917A (en) * 1964-08-07 1965-03-02 Leichsenring Max Signalling means for indicating change in speed of an automotive vehicle
US3202161A (en) * 1961-11-14 1965-08-24 Wagner Electric Corp Engine safety control device and system
US3273552A (en) * 1964-07-15 1966-09-20 Plath Walter Leon Spring actuated safety switch for the fuel supply linkage of an internal combustion engine
US3276439A (en) * 1964-05-28 1966-10-04 Briggs & Stratton Corp Dual-range governor for internal combustion engines
US3313897A (en) * 1965-07-30 1967-04-11 Gen Motors Corp Circuit controls including loadresponsive switch
US3435165A (en) * 1966-12-27 1969-03-25 Renault Electric contact units of cable control devices
US3487183A (en) * 1967-10-12 1969-12-30 Norman S Schulman Spring actuated safety switch assembly

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1055834A (en) * 1909-02-05 1913-03-11 Packard Motor Car Co Controlling mechanism for motor-vehicles.
US1097778A (en) * 1911-05-13 1914-05-26 Packard Motor Car Co Motor-vehicle.
US1833908A (en) * 1929-03-18 1931-12-01 Maybachmotorenbau Gmbh Controlling device for carburetors of internal combustion engines
US2067332A (en) * 1936-05-06 1937-01-12 Numer Harold Bolinger Control for a safer operation of motor vehicles
US2148729A (en) * 1937-06-24 1939-02-28 Carter Carburetor Corp Carburetor throttle control
US2188704A (en) * 1938-02-12 1940-01-30 Gen Motors Corp Engine throttle governor
US2260576A (en) * 1938-04-14 1941-10-28 Maybach Motorenbau Gmbh Device for safeguarding internal combustion engines against excessive speed and lubrication failure
US2313011A (en) * 1938-06-27 1943-03-02 Duwe August Apparatus for controlling the speed of revolution of machines
US2455573A (en) * 1945-07-07 1948-12-07 Bendix Aviat Corp Signal mechanism
US2517501A (en) * 1947-02-04 1950-08-01 Solex S A R L Soc Overspeed prevention device for internal-combustion engines
US2678033A (en) * 1951-01-31 1954-05-11 Sulzer Ag Internal-combustion engine exhaust control system
FR1052320A (fr) * 1951-03-13 1954-01-22 Dispositif de manoeuvre de l'organe d'étranglement qui détermine la puissance d'un moteur à combustion, plus particulièrement applicable à la conduite du moteur d'un véhicule automobile
US2836669A (en) * 1955-05-09 1958-05-27 Gaylord Prod Inc Electric switch for linkages
US2793706A (en) * 1955-06-20 1957-05-28 Edward R Moreland Safety control for automobiles
US2897806A (en) * 1957-03-05 1959-08-04 Landrum Porter Vacuum responsive throttle control for internal combustion engines
AU200061A (en) * 1960-03-09 1963-03-07 T. M. M. Research ) Limited Improvements relating tothe treatment of textile fibrous materials
US3121214A (en) * 1961-09-08 1964-02-11 Charles A Frederick Signaling system for indicating improper operation of an accelerator pedal
US3202161A (en) * 1961-11-14 1965-08-24 Wagner Electric Corp Engine safety control device and system
US3276439A (en) * 1964-05-28 1966-10-04 Briggs & Stratton Corp Dual-range governor for internal combustion engines
US3273552A (en) * 1964-07-15 1966-09-20 Plath Walter Leon Spring actuated safety switch for the fuel supply linkage of an internal combustion engine
US3171917A (en) * 1964-08-07 1965-03-02 Leichsenring Max Signalling means for indicating change in speed of an automotive vehicle
US3313897A (en) * 1965-07-30 1967-04-11 Gen Motors Corp Circuit controls including loadresponsive switch
US3435165A (en) * 1966-12-27 1969-03-25 Renault Electric contact units of cable control devices
US3487183A (en) * 1967-10-12 1969-12-30 Norman S Schulman Spring actuated safety switch assembly

Cited By (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3791366A (en) * 1970-11-10 1974-02-12 Millan C Mac Fail-safe throttle control
US3838674A (en) * 1970-12-15 1974-10-01 Peugeot & Renault Safety device for a carburettor control means
US3734230A (en) * 1970-12-17 1973-05-22 Y Tanaka Emergency stop switch means for a mobilized sledge or the like
US3731663A (en) * 1971-01-08 1973-05-08 Hollins J R Vehicle engine fuel control accelerator override
US3698372A (en) * 1971-06-08 1972-10-17 Holley Carburetor Co Throttle return spring redundancy system
US3802406A (en) * 1971-12-28 1974-04-09 Sibe Fuel feed devices for internal combustion engines
US3738347A (en) * 1972-02-14 1973-06-12 Gen Motors Corp Throttle pedal controlled pneumatically operated throttle override
US3830213A (en) * 1972-02-24 1974-08-20 Colt Ind Operating Corp Throttle return spring redundancy system
US3798402A (en) * 1972-04-19 1974-03-19 A Raab Safety switch and control system for vehicles
US3789938A (en) * 1972-04-24 1974-02-05 Artic Ets Inc Automatic shut-off switch
US3742928A (en) * 1972-05-30 1973-07-03 Zeal Corp Safety throttle for internal combustion engines
US3903864A (en) * 1972-05-31 1975-09-09 Peugeot Control device in particular for a carburetter throttle
US3757758A (en) * 1972-07-24 1973-09-11 Gen Motors Corp Throttle pedal actuated throttle return
US3760786A (en) * 1972-12-01 1973-09-25 Colt Ind Operating Corp Redundant throttle return system
US3861377A (en) * 1973-01-12 1975-01-21 Volkswagenwerk Ag Throttle valve arrangement for a combustion engine
US3924596A (en) * 1973-01-12 1975-12-09 Volkswagenwerk Ag Fail-safe throttle for an internal combustion engine
US3927657A (en) * 1973-04-05 1975-12-23 Sibe Throttle return systems for carburettors
US3881461A (en) * 1973-08-03 1975-05-06 Stanislaw F Filip Automatic power cut-off device for vehicles
US3943907A (en) * 1973-10-19 1976-03-16 Societe Industrielle De Brevets Et D'etudes S.I.B.E. Throttle return systems for carburettors
US3954151A (en) * 1974-04-29 1976-05-04 Klf Patents, Inventions, And Marketing Corporation Limited Safety control for mobile vehicles
US3952827A (en) * 1974-11-07 1976-04-27 Trw Inc. Acceleration control system
US4122819A (en) * 1976-09-22 1978-10-31 Hyster Company Fuel supply control and carburetor linkage mechanism
WO1981000696A1 (en) * 1979-09-14 1981-03-19 Towmotor Corp Vehicle brake and engine interlock
US4295540A (en) * 1979-09-14 1981-10-20 Towmotor Corporation Vehicle brake and engine interlock
US4336778A (en) * 1980-02-29 1982-06-29 Delta Systems, Inc. Safety limiter for engine speed
US5193640A (en) * 1991-01-17 1993-03-16 Lee Hae Seung Vehicle safety system for driver pedal misapplication
US5448029A (en) * 1992-11-20 1995-09-05 Regie Nationale Des Usines Renault Idling engine clutch release control device of an automatic transmission
US5653207A (en) * 1996-01-31 1997-08-05 James Clifford Sterling Diesel engine emergency shutoff device
US7140407B2 (en) * 2004-02-17 2006-11-28 Guofang Cao Configurations and designs for stump grinding teeth and corresponding holding brackets
US20050194064A1 (en) * 2004-02-17 2005-09-08 Guofang Cao Configurations and designs for stump grinding teeth and corresponding holding brackets
US20060201684A1 (en) * 2005-03-10 2006-09-14 Throttle Control Tech Inc. Throttle limiting control box for snubbing units in conjunction with service or drilling rigs
US7487839B2 (en) 2005-03-10 2009-02-10 Throttle Control Tech Inc. System for controlling the vertical movement of pipe through a stripping ram in conjunction with service or drilling rigs
US20100315072A1 (en) * 2008-02-28 2010-12-16 Arno Marto Linear Sensor
CN101960262A (zh) * 2008-02-28 2011-01-26 博格华纳贝鲁系统股份有限公司 线性传感器
US8552713B2 (en) * 2008-02-28 2013-10-08 Borgwarner Beru Systems Gmbh Linear sensor
US20100116246A1 (en) * 2008-11-11 2010-05-13 Mitsubishi Electric Corporation Throttle body for internal combustion engine
US8464688B2 (en) * 2008-11-11 2013-06-18 Mitsubishi Electric Corporation Throttle body for internal combustion engine
CN102152740A (zh) * 2010-02-11 2011-08-17 中集车辆（集团）有限公司 油门加速装置及安装有该油门加速装置的混凝土搅拌运输车
CN102152740B (zh) * 2010-02-11 2013-07-10 中集车辆（集团）有限公司 油门加速装置及安装有该油门加速装置的混凝土搅拌运输车
US8322685B1 (en) * 2010-07-23 2012-12-04 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Non-collinear valve actuator
US8939219B2 (en) 2011-05-05 2015-01-27 Snubco Manufacturing Inc. System and method for monitoring and controlling snubbing slips
US9261030B2 (en) 2013-05-20 2016-02-16 Kohler Co. Automatic fuel shutoff
US9739214B2 (en) 2013-05-20 2017-08-22 Kohler, Co. Automatic fuel shutoff
US9074535B1 (en) 2013-12-19 2015-07-07 Kohler Co. Integrated engine control apparatus and method of operating same
EP2886836A3 (en) * 2013-12-19 2015-07-22 Kohler Co. Integrated engine control apparatus and method of operating same
CN111502826A (zh) * 2020-04-22 2020-08-07 合肥康尔信电力系统有限公司 一种柴油发电机用可拆卸固定架装置及工作方法
CN111502826B (zh) * 2020-04-22 2021-04-06 合肥康尔信电力系统有限公司 一种柴油发电机用可拆卸固定架装置及工作方法

Also Published As

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DE2155681A1 (de) 1972-05-18
GB1367152A (en) 1974-09-18
IT940384B (it) 1973-02-10
FR2113736A5 (enExample) 1972-06-23
CA953171A (en) 1974-08-20
SE372059B (enExample) 1974-12-09

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