Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D1/00—Controlling fuel-injection pumps, e.g. of high pressure injection type
  • F02D1/02—Controlling fuel-injection pumps, e.g. of high pressure injection type not restricted to adjustment of injection timing, e.g. varying amount of fuel delivered
  • F02D1/04—Controlling fuel-injection pumps, e.g. of high pressure injection type not restricted to adjustment of injection timing, e.g. varying amount of fuel delivered by mechanical means dependent on engine speed, e.g. using centrifugal governors
  • F02D1/045—Controlling fuel-injection pumps, e.g. of high pressure injection type not restricted to adjustment of injection timing, e.g. varying amount of fuel delivered by mechanical means dependent on engine speed, e.g. using centrifugal governors characterised by arrangement of springs or weights

Definitions

• This invention relates to a governor for fuel injected internal combustion engines, and more specifi ⁇ cally, to such a governor that provides multiple amounts of regulation.
• Governors for fuel injected internal combustion engines typically include a so-called flyweight assembly which is driven by the engine and which, proportional to engine speed, compresses a spring.
• the spring is also compressed by a control assembly such as a throttle linkage and the axial length of the spring, and changes therein due to varying compression, dictates the amount of fuel injected into the engine.
• positioning of conventional racks which control indi- vidual fuel injectors is proportional to the axial length of the spring.
• the governing of the engine speed is achieved generally as follows. For a given throttle setting, under a no-load condition, the engine speed will be at some predetermined value. If a load is applied to the engine, and no commensurate increase in fuel is provided, the engine will begin to slow down under the load. As a result, flyweights in the governor will move radially inwardly since the centrifugal force moving the flyweights outwardly will decrease with the decreasing engine speed. This movement of the fly ⁇ weights will lessen the degree of compression of the spring so that the spring's axial length will increase.
• the no-load speed of the given throttle setting will be somewhat higher than the loaded speed for the same throttle setting, although such is not always the case.
• the differences between the two speeds, that is, no-load speed and loaded speed for the same throttle setting is termed "regulation". For example, if, at a given throttle setting, the loaded speed of an engine is 2,000 RPM, and the no-load speed of the engine for the same throttle setting is 2,200 RPM, there is a 10% regulation factor.
• the regulation of an engine at a given throttle setting is proportional to the spring rate of the spring employed in the governor utilized on the engine.
• regulation for a given engine does not remain constant for all throttle settings. Rather, it will vary, and may vary over a considerable range and may even become negative, i.e., when load is removed from the engine, engine speed would decrease. Since the purpose of a governor is to reduce fuel flow when engine speed increases over a desired amount, and to increase fuel flow when engine speed decreases below a desired amount, the negative regulation would cause the opposite to occur and could result in an unstable situation to the extent that a steady state engine speed for a given loading could never be attained.
• O Specific examples would include a diesel engine utilized in a truck as well as for power generation purposes or for operating hydraulic systems as, for example, in a refuse truck with refuse compaction systems.
• a relatively high regulation is tolerable and even de ⁇ sirable.
• a relatively high amount of regulation will allow the engine to slow down noticeably indicating to the operator that a higher throttle setting and/or change in gear ratio is required.
• a low amount of regulation is desirable to prevent severe fluctuations in output frequency that would be associated with fluctuating engine speeds im ⁇ posed by varying loads.
• the engine might be selected to provide 245 brake horsepower at 2100 RPM for normal highway operation and a governor spring selected to provide an 8.6% regulation at that engine speed.
• the same governor spring, at 1300 RPM whereat the engine would develop 150 brake horsepower would provide a 30% regulation, totally unsatisfactory for power generation at 1300 RPM and 150 brake horse ⁇ power where a 3% regulation is desired.
• a governor spring were selected to provide 3% regulation at 1300 RPM, it can be shown that such a spring would provide a -7% regulation at 2100 RPM; and of course, such negative regulation is obviously undesirable.
• a governor for providing at least two different amounts of regu ⁇ lation for a fuel injected internal combustion engine has a rotatable flyweight assembly adapted to be driven by the engine.
• a first spring is disposed to be com ⁇ pressed by the flyweight assembly proportional to engine speed and one of the flyweight assembly and the first spring is adapted to be connected to a fuel injection system for the engine to control the same.
• a control lever is associated with the first spring in opposition to the flyweight assembly for compressing the first spring proportional to a desired engine speed.
• a second compressible spring along with means for selectively engaging or disengaging the control lever and the second spring to provide one amount of regulation when the second spring is en ⁇ gaged with the control lever and a second, different amountof regulation when the second spring is disen- gaged from the control lever.
• the single Fig. is a partial schematic, partial mechanical drawing of a governor made according to the invention with parts shown in section for clarity.
• FIG. 1 An exemplary embodiment of a governor 11 made according to the invention is illustrated in the Fig. in connection with a diesel engine, shown schematically at 10, and which is provided with a fuel injection system, shown schematically at 12, typically of the type wherein the amount of fuel delivered during each injection cycle is controlled by the position of a- reciprocal rack 14 movable in a path illustrated by an arrow 16.
• the position of the rack 14, and thus the quantity of fuel injected is controlled by a connec ⁇ tion, directly or indirectly, to the toes 18 of a plu ⁇ rality of flyweights 20, only one -of which is shown.
• the flyweights 20 are mounted by pivots 22 and additionally, are rotatable, being driven by the engine 10 as schematically illustated at 24.
• Various con ⁇ structions for the flyweights 20, the pivots 22 and the rotatable drive 24 are well known and form no part of the present invention.
• the toes 18 of the flyweights 20 bear against a plate 26 abutting one end of a main governor spring 28.
• the opposite end of the spring 28 is abutted by a plate 30 which in turn is positioned " by one end 32 of a control lever 34 and again, the construction can be according to any known means.
• the control lever 34 is operable, as will be seen, to compress the spring 28 in accordance with a desired throttle setting.
• the toes 18 of the flyweights 20 operate to compress the spring 28 dependent upon actual engine speed.
• the position of the rack 14, and thus the quan ⁇ tity of fuel injected is dependent upon the position of the lefthand end of the spring 28 as viewed in the Fig.
• Movement of the lever 34 is effected, in one mode of operation, by a throttle linkage shown sche ⁇ matically at 36.
• the throttle linkage 36 is connected to a rotary shaft 38.
• the lever 34 intermediate its ends, includes at least one apertured tongue 40.
• the aperture 42 in the tongue mounts the lever 34 for ro ⁇ tation on the shaft 38. That is, the lever 34 is not fixed to the shaft 38 for rotation therewith but may rotate relative thereto for certain conditions tobe seen
• the shaft 38 fixedly mounts a collar 44 which in turn includes an axial projection 46 which is de ⁇ signed to overlie one of the tongues 40.
• One side sur ⁇ face 48 of the projection is adapted to engage an edge 50 of the tongue 40 when the shaft 38 is rotated suf ⁇ ficiently clockwise to cause engagement between the two.
• a central slot having a bottom shown at 54.
• Received within the slot is an elongated piston rod 56 mounting a piston 58 on one end thereof.
• the piston 58 is received reciprocally in a cylinder bore 60. Fluid under pressure may be ported by means 61 to the left side of the piston 58 to drive the same to the solid line position illustrated in the Fig. within the bore 60.
• the bore 60 also contains a return spring 62 for driving the piston 58 to the dotted line position within the bore 60.
• the end of the piston rod 56 remote from the piston 58 mounts a retainer 64 against which is abutted a stepped bushing 66.
• Reciprocally mounted on the piston rod 56 is an oppositely directed, but similar stepped bushing 68 and a compressible coil spring 70 is mounted between flanges of the respective bushings 66 and 68.
• the bifurcated end 52 of the control lever 34 is abutted by the bushing 68 when the piston 58 " is in the solid line position illustrated in the drawing.
• the degree of compression of the spring 70 will depend upon the extent to which the piston 58 moves to the right as viewed in the Fig. and this is limited by an adjustable stop 72 in the form of a threaded shaft having a end 74 which may abut the piston 58.
• the adjustable stop72 is threaded in an end cap 76 for the bore 60 and extends externally thereof to terminate in a slotted operator 78.
• a screwdriver may be inserted in the slotted operator 78 to adjust the axial position of the stop 72 within the bore 60 and once the desired position is attained, a lock nut 80 may be tightened to maintain such positioning.
• the end cap 76 closes one end of the bore 60 in a housing part 82 which in turn is fastened to a main housing 84 by means of cap screws 86 or the like.
• the housing 84 extends about the various components illustra ⁇ ted, the major ones of which include the flyweight as ⁇ sembly, the springs 28 and 70, the control lever 34, the control shaft 38, the limited lost motion connection defined by the side surface 48 and the edge 50, and with the housing part 82 enclose the piston 58 as well as the adjustable stop 72.
• the main governor spring 28 is chosen by known methods to have a spring rate that will provide the 8.6% regulation desired at
• the throttle linkage 36 is placed in the low idle position, for example, one whereat engine speed will be approximately 600 RPM under a no-load condition.
• the collar 44 is then fixed to the shaft 38 at an angular position whereat the side surface 48 of the projection
• the throttle linkage 36 is such as to rotate
• the piston 58 is in its dotted line position, being urged thereto by the return spring 62 and does not affect engine operation.
• the throttle link ⁇ age 36 is returned to its low idle position, typically by a spring in the linkage itself without any intervention by the operator. Fluid under pressure is applied by means 61 to the left side of the piston 58 to drive the same against the stop 72. This in turn brings the bushing 68 into contact with the lever end 52 and provides some degree of compression of both the spring 70 and the spring 28. It will be appreciated that upon such occurrence, the springs 28 and 70 will be acting in series against the toes 18 of the flyweights 20 and thus, the spring rate of the system will be different from the spring rate of the spring 28 alone.
• the spring 70 is chosen to have a spring rate which, when the geometry of the lever 34 is also considered, when combined with the spring rate of the spring 28 will provide a system spring rate that will correspond to a 3% regulation at 1300 RPM.
• the stop 72 is, of course, adjusted to limit movement of the spring 70 to a position that provides the desired fixed engine speed, here 1300 RPM.
• the two regulations may be accurately set at the factory using sophisticated equipment such as dyno ometers and ordinarily will require no adjustment in the field. However, where adjustment may be required, it can be accomplished through the simple act of uti ⁇ lizing the external operator 78 for the stop 72.
• the system is practical in applications where more than two amounts of regulation are required simply by lengthening the lever end 52 and adding additional components corresponding to the spring 70 and the piston 58 configured to provide additional system spring rate variations.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• High-Pressure Fuel Injection Pump Control (AREA)

Priority Applications (9)

Applications Claiming Priority (2)

Publications (1)

Family

ID=22154536

Family Applications (1)

Country Status (9)

Cited By (1)

Citations (9)

Family Cites Families (3)

• 1980
  • 1980-09-15 WO PCT/US1980/001188 patent/WO1982001037A1/en active Application Filing
  • 1980-09-15 GB GB8200843A patent/GB2094501B/en not_active Expired
  • 1980-09-15 DE DE803050563A patent/DE3050563A1/de active Granted
  • 1980-09-15 JP JP81501513A patent/JPS57501390A/ja active Pending
  • 1980-09-15 BR BR8009106A patent/BR8009106A/pt unknown
• 1981
  • 1981-06-17 CA CA000379947A patent/CA1153646A/en not_active Expired
  • 1981-06-24 ZA ZA814270A patent/ZA814270B/xx unknown
  • 1981-09-07 BE BE0/205882A patent/BE890244A/fr not_active IP Right Cessation
• 1984
  • 1984-11-08 HK HK863/84A patent/HK86384A/xx unknown

Patent Citations (9)

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