US3797470A

US3797470A - Fuel regulating system for an internal combustion engine

Info

Publication number: US3797470A
Application number: US00225216A
Authority: US
Inventors: N Beck
Original assignee: Teledyne Industries Inc
Current assignee: TDY Industries LLC
Priority date: 1972-02-10
Filing date: 1972-02-10
Publication date: 1974-03-19
Anticipated expiration: 1991-03-19

Abstract

A fuel regulating system including provision for automatically adjusting the fuel supply as a function of increasing or decreasing engine speed. A movable sleeve member actuable by the action of a centrifugal type governor actuates a control lever which in turn regulates the quantity of fuel delivered to the engine. The control lever is further attached to a manual throttle of the cam type with an intermediate spring plunger to provide for operator adjustment of the fuel. Additionally, there is provided a pair of adjustable stops engageable with the lower end of the control lever to provide respectively low idle speed and high idle speed limits.

Description

United States Patent [191 [11] 3,797,470 Beck Mar. 19, 1974 FUEL REGULATING SYSTEM FOR AN Primary Examiner-Laurence M. Goodridge INTERNAL COMBUSTION ENGINE [75] Inventor: Norman G. Beck, Wheaton, Ill.

[73] Assignee: Teledyne Industries, Inc., Los

Angeles, Calif.

[22] Filed: Feb. 10, 1972 [21] Appl. No.: 225,216

Attorney, Agent, or Firm Hauke, Gifford, Patalidis & Dumont [57] ABSTRACT A fuel regulating system including provision for automatically adjusting the fuel supply as a function of increasing or decreasing engine speed. A movable sleeve member actuable by the action of a centrifugal type governor actuates a control lever which in turn regulates the quantity of fuel delivered to the engine. The control lever is further attached to a manual throttle of the cam type with an intermediate spring plunger to provide for operator adjustment of the fuel. Additionally, there is provided a pair of adjustable stops engageable with the lower end of the control lever to provide respectively low idle speed and high idle speed limits.

" iterat- .f Asmmwnx FUEL REGULATING SYSTEM FOR AN INTERNAL DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Reference is made to FIG. 1 in which the basic parts The present invention is related to internal combus- 5 of the fuel regulating system and their cooperative relation engines, and more particularly to a fuel regulating or governing system for such engines for controlling and suitably limiting the quantity of fuel being supplied during their operation.

A variety of types of fuel governors have been developed for internal combustion engines both to limit the speed of the engine and the amount of fuel supplied to the engine. Governors of different types also have been incorporated which automatically increase the amount of fuel supplied to the engine when the engine is subjected to an increased load, such as for example when the vehicle is being driven uphill. It is typical of prior art governors that they increase the fuel supply to the maximum allowable amount whenever an increased engine load is encountered thus providing a waste of fuel, with resultant uneven torque characteristics for the engine.

In addition, fuel regulator systems of the prior art typically have a throttle control, such as a gas pedal directly linked to the governor mechanism, in order to enable the operator of the engine to provide a maximum fuel flow at any time by actuating the manual throttle. One major disadvantage of such a fuel regulating system becomes apparent when the operator applies maximum throttle to force maximum fuel flow when the vehicle is traveling at low to intermediate speeds, thereby wasting fuel and contributing to an uneven torque performance of the engine. The resultant operating characteristics of the engine with such a control system provide an uneven ride to the vehicle and its passengers.

SUMMARY OF THE PRESENT INVENTION It may be stated that a primary object of the present invention is to provide a fuel regulating system for internal combustion engines which controls the fuel input to the engine in a gradual manner, contributing to smooth engine torque characteristics and to the reduction of fuel waste.

It is also an object of the present invention to provide a governing fuel regulating system which has means for ready adjustment of both idling speed and of the maximum allowable engine speed.

The above objects and others which will become obvious are achieved through a particular fuel regulating I system incorporating a control lever used in conjunction with a particular type of cam operated throttle control and linkage.

BRIEF DESCRIPTION OF THE DRAWING The present invention will be described in the accompanying specification and in the drawings in which like reference characters are used to refer to like elements where they occur in the Figures, and wherein:

FIG. 1 is a combined diagrammatic and crosssectional view of the fuel regulatingsystem with parts broken away; and FIG. 2 is a view substantially identical to that of FIG. 1 showing the parts in a movedposition responsive to operation of the engine at increased and relatively high speeds.

tionship are shown. The fuel control system is particularly adapted for use in an internal combustion engine, for example of the type as is disclosed in W. F. lsley et al., U. S. Pat. No. 3,338,224 for Fuel Control Mechanism issued on Aug. 29, 1967, which patent is of common ownership with the present application. A cam operated, spring loaded throttle mechanism is incorporated which includes a fuel control rod 10. The fuel control rod 10 is movable transversely to control the fuel flow to the engine so that with a movement of the rod 10 to the left fuel flow is increased, while with its movement to the right fuel flow is decreased. The throttle mechanism includes a cam 12 rotatably mounted on a shaft 14. The shaft 14 is manually rotatable by the operator to control the amount of fuel being fed to the engine. Connected intermediate the right hand end of the rod 10 and the cam 12 is a spring plunger connecting means indicated generally by the numeral 16. It will be seen that the right hand end of the rod 10 is fixed to a piston 18, which piston is movable longitudinally in a cylinder 20 against a force ex-- erted by a compression spring 22. The cam 12 has its major projection engageable against a second piston 24 abutting against the right hand end of the spring 22. The cam 12 is illustrated in FIG. I with one of its relatively low cam lobes in engagement with the right hand end of the piston 24.- The high side of the cam 12 is indicated by the numeral 12a, which indicates that part of the cam 12 which is manually adjusted into engagement with the piston 24 when the operator has set a speed maximum. The basic throttle parts just referred to are encased in a cover 26, which cover in turn is mounted on one of the engine enclosure side frames shown in part and identified by the numeral 28.

Other parts of the fuel regulating system are illustrated with respect to their relative placement in the engine enclosure, without indicating the complete structure of such enclosure in the interest of simplification and brevity. Also cooperable with the manually operated throttle is a maximum fuel limit which is provided by the associated mechanism indicated by the numeral 30 at the upper left hand side of the drawing. This mechanism includes a shaft 32 journalled in a vertical side frame 34, with an adjusting nut 36 shown mounted upon a threaded portion 38 of the shaft 32. An adjustable stop 40 is shown mounted in the path of the leftward movement of the rod 10 to provide a maximum fuel flow limit by reason of the abutment of a cam nose 42 with a cooperating raised portion 44 of the stop 40. The stop 40 is fixed to the shaft 32 through a bracket 46. It will be seen that the rod 32 is adjustable laterally by the nut 36 to adjust for maximum fuel flow. A linkage 48 is operably connected to the fuel pump for the engine. The detail of such linkage has been omitted in the interest of brevity. The basic function is to reduce the fuel provided to the engine whenever the cam nose 42 comes into engagement with the raised portion 44. Reference is made to the aforementioned U.S. Pat. No. 3,338,224 for a description of the mechanism associated with the maximum fuel control system just briefly referred to.

The major operating part of the fuel regulating systern is a control lever 50 which carries fixed at its upper end, according to the present invention, the cam nose 42 already described. The lever 50 is pivotally mounted by a pin 52 to an engine speed responsive means illustrated as a sleeve 54, which sleeve 54 moves longitudinally responsive to the speed developed by the engine. For this purpose, the left hand end of the sleeve 54 terminates in a flange 55 which is maintained in contact with a speed responsive device of the centrifugal governor type. The governor includes a shaft 56 which is coupled through a suitable connecting mechanism to the engine crankshaft or other similar engine rotating part so that the shaft 56 is rotated at a rate proportional to engine rotation. At the right hand end of the shaft 56 are connected upper and

lower brackets

58 and 60, respectively. An upper L-shaped weight 62 is rotatively pinned to the bracket 58 by a stud 64. A lower L- shaped weight 66 is rotatively pinned to the bracket 60 by a stud 68. It will be seen that as the engine speed is increased there will be a tendency for the

weights

62 and 66 to be swung outwardly and thus apply a force against the left hand end of the sleeve 54 to displace it in a rightward direction. At the right hand end of the sleeve 54 there is provided a stop abutment 70 which is fixed to the side frame 28. Contained between a retaining recess .72 in the abutment 70 and an open end 74 at the right hand end of the sleeve 54 is a compression spring 76. The spring 76 will be seen to provide a yieldable force against the longitudinal displacement of the sleeve 54 in a rightward direction.

The lever 50 further has pivotally mounted at its lower end a lower end portion 78. The end portion 78 is slidably mounted on a rail 81 and is engageable according to the direction of the pivoting movement of the lever 50 against a left hand stop 80 or a right hand stop 82. The left hand stop 80 represents a low idle speed stop which is adjustable. This adjustment is provided through a shaft 82 on which the stop 80 is mounted and through a threaded portion 84 of the shaft 83 on which an adjusting nut 86 is mounted. The right hand stop 82 represents an adjustable high idle speed stop. The selective adjustment of the right hand high idle speed stop 82 is similarly afforded through a shaft 88 to which the stop 82 is fixed and through the rotation of a nut 90 upon a threaded portion 92 at the right hand end of the shaft 88. A second compression spring 94 is connected between the right hand side of the lower end portion 78 of the lever 50 and the left hand surface of the stop 82. The spring 94 will be seen to provide a continuous but yieldable biasing force which tends to rotate the lever 50 in a clockwise manher about the pin 52 so as to move the upper fuel control rod in a rightward fuel decreasing direction. This movement and the control over the fuel control rod 10 is provided through a pivotable pin 96 connection between the upper end of the lever 50 and an enlarged portion 98 formed in the fuel control rod 10 and further by a pivotable pin 79 connection between the lower end portion 78 with the lower end of the lever 50. It will be seen that the parts in the FIG. 1 drawing are shown in an operating condition of the engine at relatively low speed before the fuel control system with which the present invention is concerned has become fully operable.

The parts in the FIG. 2 drawing are illustrated in a moved position which they occupy when the engine speed has been substantially increased so as to provide a rightward movement of the sleeve 54.

DESCRIPTION OF OPERATION Description will now be made of the operation of the fuel regulating system provided according to the present invention. The engine is started and there is initially provided by the operator a rotation of the shaft 14 to which the cam 12 is fixed. Rotation of the cam 12 in a counterclockwise direction will being the high side of the cam 12a into contact with the spring biased plunger 16 to provide a leftward force to fuel control rod 10, thus providing an increased flow of fuel to the engine. The engine is thus supplied with fuel in excess over that amount necessary to start it. After the engine has begun firing, the cam member 12 may be turned clockwise by the operator to rotate the cam high side 12a upwardly. This permits the piston 12 to move rightwardly, thus reducing the force exerted by the spring 22 in a leftward direction against the piston 18 and against the right hand end of the rod 10. During continued idling operation of the engine at low engine speeds, the lever 50 will be maintained in a substantially vertical position as illustrated in the FIG. 1 drawing. Otherwise stated, there has not yet been initiated any movement of the speed responsive means, namely, the sleeve 54 attached to the engine through the centrifugal type governor including the shaft 56. The lower end portion 78 of the lever 50, due to the force exerted by the compression spring 94, will be maintained against the lower left hand stop which is the low idle speed stop. As has previously been indicated, the low idle speed stop is adjustable according to the lateral positioning of the stop 80 by means of the rotation of the adjusting nut 86 on the threaded portion 84 of the shaft 83. In the event a higher engine idle speed is desired, the stop 80 is moved rightwardly to cause a pivoting of the control lever 50 about the pin 52, thus allowing a slight further leftward movement of the fuel control rod 10 in the direction of increasing fuel flow to the engine. If it is desirable to reduce the engine idling speed, a corresponding correction in the opposite direction is made by the positioning of the stop 80.

The operator of the vehicle may now accelerate the engine by turning the cam 12 in a counterclockwise direction to place its cam high side 12a into abutment with the right hand end of the piston 24, thus forcing the fuel control rod 10 in a leftward direction to increase fuel flow to the engine. If a relatively hard acceleration is provided, the lever 50 will be pivoted rapidly in a counterclockwise direction around its mounting pin 52. However, since the speed of the engine cannot be changed as abruptly as the cam 12 can be manually rotated by the operator, there is a lag and the sleeve 54 remains in a stationary position for a short period of time. Therefore, the spring 94 will undergo a greater force of compression than that which is exerted against the spring 22. In this manner, the cam nose 42 is maintained away from engaging the raised portion 44 of the maximum fuel flow stop 40 so that the fuel to the air ratio is kept at a level below the maximum allowable. Thus, smooth and even engine torque characteristics are achieved along with a relatively smooth engine acceleration. An additional advantage is that fuel is conserved by reducing the fuel-air mixture while the engine is still under acceleration.

As the acceleration of the engine is continued, the condition illustrated in the FIG, 2 drawing will result. The increased speed of rotation of the governor shaft 56 will cause a pivotal movement of the

weights

62 and 66 so that their portions 62a and 66a are forced into engagement with the left hand end of the sleeve 54, causing its displacement in a rightward direction. This movement in a rightward direction results in a compression of the spring 76. In addition, the rightward motion of the sleeve 54 will result in a corresponding displacement of the lower end portion 78 of the lever 50 until it is placed into abutment with the left hand surface of the right hand stop 82. The stop 82, as has already been indicated, represents the high idle speed stop and is laterally adjustable according to the rotation of the adjusting nut 90 on the threaded portion 92 of the shaft 88. If there is a further increase of engine speed, there will be a still further movement of the sleeve 54 rightwardly. This additional movement of the sleeve 54 will cause a rotation of the lever 50 in a clockwise direction around its pivot point provided by the pin 52. This will result in a rightward movement of the upper fuel control rod by reason of the pin connection between it and the upper end of the lever 50.

This rightward movement of the fuel control rod 10 is thenin a direction effective to decrease the fuel being supplied. to the engine.

To throttle the engine back so that the fuel control returns to the position shown in FIG. I the cam 12 is rotated to engage its low side with the piston 24. This permits the spring 22 to expand and relieves the force acting on piston 18. This permits the spring 94 to urge the end portion 78 along the rail 81 thus moving the rod 10 gradually and smoothly in a fuel decreasing direction. Finally the engine speed is reached which permits the engine sleeve 54 to return to an idling position and the spring 76 then aids in moving the end portion 78 of the control rod against the low idle stop 80.

It will be seen that there has been provided by the present invention a substantially improved fuel regulating system which includes an improved cam type throttle and biasing spring arrangement, with an additional control which places an upper limit on the amount of fuel and on the amount of acceleration that can be provided to the engine. Through the adjustable high and low idle stop mechanism, there is provided a both improved and simplified arrangement for such adjustments.

What is claimed is as follows: 1. In a fuel regulating system for an internal combustion engine having a fuel control rod movable axially to increase and decrease fuel flow to the engine, the improvement comprising,

a lever pivotally mounted to said rod and operable to move said rod axially upon movement of said lever,

said lever being pivotal about an intermediate point and about a lower point whereby pivotting of said lever about either of said pivotal points moves said lever to regulate fuel flow to said engine,

means connected with said lever at said intermediate pivotal point to move said intermediate pivotal point linearly parallel with the axis of said fuel control rod in response to changes in the speed of said internal combustion engine, means mounting the lower end of said lever for linear movement parallel to movement of said fuel con-v 2. The fuel regulating system as defined in claim 1,

and in which said last mentioned means comprises a cylinder, said fuel control rod having a flange portion at one end disposed within said cylinder,

a cam member rotatable between a number of positions and engaging a member carried within said cylinder to urge said member into said cylinder to an extent determined by the lobes of said cam member and a spring disposed between said member and said flange portion to transmit movement of said member through said spring and to said flange to thereby urge said fuel control rod in a fuel regulating direction.

3. The system as defined in claim 1 and in which said lower mounting means for said lever includes adjustable stop members limiting linear movement of the lower end of said lever one of said adjustable stop members providing low idle speed limit means and the other of said stop members providing high idle speed means.

Claims

1. In a fuel regulating system for an internal combustion engine having a fuel control rod movable axially to increase and decrease fuel flow to the engine, the improvement comprising, a lever pivotally mounted to said rod and operable to move said rod axially upon movement of said lever, said lever being pivotal about an intermediate point and about a lower point whereby pivotting of said lever about either of said pivotal points moves said lever to regulate fuel flow to said engine, means connected with said lever at said intermediate pivotal point to move said intermediate pivotal point linearly parallel with the axis of said fuel control rod in response to changes in the speed of said internal combustion engine, means mounting the lower end of said lever for linear movement parallel to movement of said fuel control rod and including mans urging said lower end to a linear position in which said lever is pivotted about said intermediate pivot point toward a position urging said fuel control rod in a fuel decreasing direction, and means for manually moving said fuel control rod to thereby pivot said lever about said intermediate and lower pivot points.

2. The fuel regulating system as defined in claim 1 and in which said last mentioned means comprises a cylinder, said fuel control rod having a flange portion at one end disposed within said cylinder, a cam member rotatable between a number of positions and engaging a member carried within said cylinder to urge said member into said cylinder to an extent determined by the lobes of said cam member and a spring disposed between said member and said flange portion to transmit movement of said member through said spring and to said flange to thereby urge said fuel control rod in a fuel regulating direction.