US3911885A

US3911885A - Torque rise limiting governor

Info

Publication number: US3911885A
Application number: US519578A
Authority: US
Inventors: James T Hammond
Original assignee: Caterpillar Tractor Co
Current assignee: Caterpillar Inc
Priority date: 1974-10-31
Filing date: 1974-10-31
Publication date: 1975-10-14
Anticipated expiration: 1992-10-14
Also published as: GB1470742A; DE2540574A1; BR7507042A; CA1013629A; JPS5151631A

Abstract

A torque rise limiting governor for an internal combustion engine includes a spring arrangement which urges a fuel control member to a maximum fuel delivery position when the engine speed decreases due to increased loading, a limiting device for establishing the maximum fuel delivery position, and a lever device pivotal about the limiting device to move the fuel control member in a direction for decreasing delivery of fuel to the engine when the engine speed decreases due to increased loading thereon after the fuel control member reaches its maximum fuel delivery position.

Description

United States Patent 11 1 Hammond Oct. 14, 1975 [54] TORQUE RISE LIIVIITING GOVERNOR 3,777,730 12/1973 Gates et a1. 123/140 R [75] In entor: James T. nd, Tremont, In. 3,818,883 6/1974 Glassey 123/140 R [73] Assignee: ,Caterpillar Tractor Company, Primary Examiner-Wendell E. Burns Peoria, 11]. Assistant Examiner-James Winthrop Granson, Jr. I Filed Oct 31 1974 Attorney, Agent, or FirmRalph E. Walters [21] Appl, No.: 519,578 [57] ABSTRACT A torque rise limiting governor for an internal com- 52 US. Cl 123/140 R; 123/140 MC bustio" engine includes a Spring arrangement which 51 int. (:1. F02D 1/04 urges a fuel comrol member to a maximum fuel deliv- [58] Field of Search. 123/139 Aw 140 R 198 D ery position when the engine speed decreases due to 123/198 DR 140 MC 140 Mp increased loading, a limiting device for establishing 7 the maximum fuel delivery position, and a lever device [56] References Cited pivotal about the limiting device to move the fuel control member in a direction for decreasing delivery of UNITED STATES PATENTS fuel to the engine when the engine speed decreases 3,145,624 8/1964 Parks et a1. 123/140 R due to increased loading thereon after the fuel control Egg/ 3 member reaches its maximum fuel delivery position. 3:577:968 5 1971 Staudt et a1 123/140 R 9 Claims, 3 Drawing Figures TORQUE RISE LIMITING GOVERNOR BACKGROUND OF THE INVENTION In compression ignition engines the fuel control rack is usually maintained in its maximum fuel delivery position under lug conditions thereby establishing the natural torque rise of the engine. Torque rise is defined as the inherent increase in the output torque of the engine when the engine speed decreases from the full load speed due to increased loading on the engine. When the natural torque rise is too great, the fuel is inefficiently and incompletely burned resulting in excessive engine heat and an increase in the noxious exhaust emission and smoke from the engine.

A solution to the above problem is to provide a mechanism for controlling the amount of torque rise of the engine during critical lugging conditions. Such mechanisms are taught by the constructions disclosed in the U.S. Pat. application Ser. No. 409,864 filed Oct. 26, 1973 by Clouse et al. and assigned to the assignee of the present application. Such devices are utilized in combination with the usual governor configurations and are operative to reduce the volume of fuel delivered to the combustion chambers of the engine when the speed of the engine decreases due to a load imposed thereon. The reduction of fuel controls the torque rise of the engine and minimizes the noxious exhaust emissions therefrom. However, such devices are relatively complex requiring additional componentry for use with the governor which resultsin a significant increase in the cost of manufacturing the governortorque rise limiting device combination.

OBJECTS OF THE INVENTION Accordingly, an object of this invention is to provide an improved torque rise limiting governor for controlling the torque rise experienced by the engine during lugging conditions.

Another object of this invention is to provide such a torque. rise limiting governor which decreases the amount of noxious exhaust emissions from the engine during lugging conditions.

Another object of this invention is to provide an improved torque rise limiting governor of the character described which is simple in design and economical to manufacture.

Other objects and advantages of the present invention will become more readily apparent upon reference to the accompanying drawing and following description.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a longitudinal vertical sectional view through a portion of a torque rise limiting governor embodying the principles of the present invention.

FIG. 2 is an isometric view of certain elements of the torque rise limiting governor of FIG. 1.

FIG. 3 is a section view and partial elevation taken along the line IlIllI of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly to the drawing a torque rise limiting governor embodying the principles of the present invention is generally indicated by the reference numeral in association with and for controlling the position of a fuel control member 11 of an internal combustion engine, not shown. The basic governor configuration is generally of the type described in the US. Pat. Nos. 3,125,624 and 3,532,082 issued to Parks et al. and Clouse et al. respectively both of which are assigned to the assignee of the present application. The governor 10 includes a housing partially shown at 12 having a cylindrical portion 13 and a pair of

concentric bores

14 and 16 formed within the cylindrical portion in axial alignment with the fuel control member. A spring seat retainer 17 is axially slidably disposed on the cylindrical portion and has a radially outwardly extending flange 18 formed thereon engagable by a throttle control lever partially shown at 19. An elongated rod 21 is slidably disposed in bore 14 and has a contact plate 22 secured to one end thereof adapted for engagement with a spring blade stop 23 secured to the housing while a flange 24 is formed on the opposite end of the rod.

A pair of substantially L-shaped flyweights 26 are pivotally mounted on a rotatable carrier, not shown, and are responsive to the speed of the engine. Each flyweight has a radially inwardly extending arm 27 adapted to contact a thrust member 28 mounted on a tubular projection 29 of an annular spring seat collar 31. The collar has an axially aligned bore 32 extending therethrough and is axially slidably disposed on the fuel control member. A governor spring 33 is disposed between the collar and the spring seat retainer 17. Two pair of spaced apart lugs 36 are formed on the annular collar 31 and extend toward the cylindrical portion 13. The lugs form a pair of diametrically opposed spaces 37 which are more clearly shown in FIG. 3.

A two piece cylindrical housing 38 has an end wall 39 in abutment with the annular collar 31. A bore 41 extends through the end wall and slidably receives the fuel control member 11. The cylinder is constructed from a pair of symmetrical halves 42 fastened together by a pair of annular retainer rings 43 forming a spring chamber 44. An end wall 46 at the opposite end of the housing has an aperture 47 formed therein with the rod 21 extending through the aperture such that the flange 24 is disposed within the spring chamber and adapted for engagement with the inside of the end wall 46. The housing has a pair of diametrically opposed openings 48 adjacent to the end wall 39 with the openings forming a pair of parallel flat surfaces 49. A pair of corners 51 are formed at the juncture of the flat surfaces and the inner face of the end wall.

Each of a pair of levers 52 has an end portion 53 disposed within the space 37 between the lugs 36 and is pivotally secured to the collar 31 by a pivot pin 54. The levers individually extend substantially radially inwardly through the openings 48 in the housing 38 with each lever having a pair of bifurcated fingers 56 straddling the fuel control member 11. An enlarged annular flange 57 is secured to the end of the fuel control member and is slidably disposed within the spring chamber 44 of the housing. The fingers of the levers are disposed between the flange and the end wall 39. A helical spring 58 is contained within the spring chamber in a compressed condition between the end wall 46 and the flange 57 such that the bias of the spring and the coaction of the flange, levers and end wall 39 normally maintains the end wall 39 in abutment with the collar :"OPERATION While the operation of .the present invention is believed clearly apparent from the foregoing description further amplificationwill subsequentlybe made in the following briefsu mmary of such operation. For the purpose of describing the operation of the torque rise limiting governor 10. of the present inventiomthe housing 12 is to be considered as stationary while movement of all other elements is relative to the housing.

a The function of the governor is to maintain the engine speed'within a predetermined speed range by adjusting the position of the fuel control member 11 in the usual manner as the load on the engine varies. During normal operating conditions the housing 38, fuel control member 11, collar 31 and the levers 52 are positioned slightly to the left of the position shown in FIG. 1 and'mo'ye in unison due to the force of the spring 58. The predetermined speed range is established by manual positioning of the throttlecontrol lever 19 in the usualmanner to provide a preload force on the governor spring'33 to act against the centrifugal force of the flyweights 26. Movement of the control lever to the right, as viewed in FIG. 1, resultsin movement of the collar and the fuel control member to the right to increase the volume of fuel delivered to the engine to increase the engine speed. Movement of thelever to the left results in moving the fuel control member to the left toidecrease the supply of fuel to the engine to decrease'eng'in'e speed. When the desired speed of the engine is ob'ta'ined the centrifugal force on the flyweights exerts an axial force through the arms 27 to counterbalah'cetlie: axial force of the governor spring 33 thus establishing an instantaneous position of the fuel control member.-

' When-the load on the engine is increased the engine speed'decreases' resulting in a corresponding reduction in the centrifugal force of the flyweights 26 thereby allowing the governor spring 33 to move the collar 31 and the fuel control member llto the right for supplying more fuel to the engine to maintain the engine speed within the desired range.

As the fuel control member 11 is moved tothe right under increasing engine loads, the end wall 46 of the housing 38 engages the flange 24 of the rod 21 which has a fuel limitin'g effect preventing further'rightward movement of the fuel control member 11 and thus establishing a maximum fuel delivery position of the fuel control member. The maximum fuelposition normally establishes the full load speed of the engine.

As the load on the engine continues to increase above the normal operating range, engine speed drops and the centrifugal force of the flyweights 26 acting on the collar 21 and governor spring 33 also decreases. This causes the -governor to become imbalanced in that the governor spring'continues to urge the collar 31 to the right away from the end wall 39 of the housing 38.'

Since the pivot pins 54 move with the collar, the levers 52 pivot about;the corners 51 which act as a fulcrum for the levers. As the levers pivot about the corners the fingers 56 move to the left relative to the corners thereby moving the fuelcontrol member 11 to the left thereby reducing the volume of fuel supplied to the engine. The reduction in fuel during lugging limits the amount of torque rise of the engine. The leftward movement of thefuel control member continues until the bias of the spring 58 balances the available force from thegover'nor spring. A further reduction in the engine speed as a result of greater loading will consequently result in further leftward movement of the fuel control member decreasing the supply of fuel to the engine.

When the load on the engine is relaxed and the engine speed increases the centrifugal force applied to the collar 31 by the flyweights 26 increases. This moves the collar and pivot pins 54 to the left permitting the spring 58 to return the fuel control member 11 toward the maximum fuel position with the position of the fuel control member being subsequently controlled by the normal operation of the governor.

In view of the foregoing it is readily apparent that the structure of the present invention provides an improved torque rise limiting device which reduces the volume of fuel delivered to the engine when the engine speed is reduced below its full load speed due to greater loading-of the engine. This permits more efficient and complete combustion of the fuel to minimize the emission of noxious matter from the engine. The elements added to the governor for accomplishing this are simple in design and few in number which will minimize the manufacturing costs of the governor.

While the invention has been described and shown with particular reference to the preferred embodiment, it will be apparent that variations might be possible that would fall within the scope of the present invention which is not intended to be limited except as defined in the following claims.

What is claimed is:

l. A torque rise limiting governor for controlling the position of a fuel control member of an internal combustion engine, comprising;

an annular collar slidably disposed on the fuel control member; .spring means resiliently urging said collar and the fuel control member in a first direction for increasing delivery of fuel to the engine; a flyweight arrangement responsive to engine speed i normally to counterbalance the bias of said spring means and operative to permit the spring means to move the collar and the fuel control member in said first direction when the engine speed decreases due to increased loading thereon;

means for limiting movement of the fuel control member in said first direction establishing a maximum fuel delivery position of the fuel control member; and

lever means pivotally attached to the collar and engagable with the fuel control member and said limiting means for pivoting about the limiting means to move the fuel control member in a second direction for decreasing delivery of fuel to the engine when the engine speed decreases due to increased loading thereon after the fuel control member reaches its maximum fuel delivery position.

2. The torque rise limiting governor of claim 1 wherein said lever means cooperates with said limiting means for limiting movement of the fuel control member in said first'direction.

3. The torque rise limiting governor of claim 2 including a housing having a stop member engagable by said limiting means for limiting movement of the fuel control member in said first direction.

4.The torque rise limiting governor of claim 3 wherein said limiting means includes engagement means disposed between said collar and said lever means and being movable in said first direction in unison with the collar and the fuel control member until said limiting means engages said stop member, said lever member being disposed for pivoting about said engagement means to move the fuel control member in said second direction after said limiting means engages said stop member.

5. The torque' rise limiting governor of claim 4 wherein said lever means includes a'pair oflevers pivotally secured to the collar diametrically opposite to each other and extending radially inwardly towards the fuel control member.

6. the torque rise limiting governor of claim 5 wherein said limiting means includes a cylindrical housing having an end wall and a pair of openings disposed adjacent to said end wall, said levers extending through said openings and wherein said engagement means is said end wall.

7. The torque rise limiting governor of claim 6 wherein said fuel member has an annular flange secured thereto and wherein said end wall has an opening formed therein with said fuel control member extend, ing through said opening with said levers disposed between said flange and said end wall.

8. The torque rise limiting governor of claim 7 wherein said spring means includes a helical spring disposed within said cylindrical housing and normally resiliently urging said flange to a position engaging said levers with said levers urging said end wall of said housing into engagement with said collar.

9. The torque rise limiting governor of claim 8 wherein said cylindrical housing has an opposite end wall having an aperture therethrough, said limiting means including an elongated rod having opposite ends with one of said ends having a contact plate secured thereto for engagement with said stop member while the other of said ends extends through said aperture of said opposite end wall and has a flange secured thereto for engagement with said opposite end wall to limit movement of the cylindrical housing in said first direction.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,911,885 DATED 1 October l t, 1975 INVENTOR( 1 James T. Hammond it is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the Title Page, Item [73], change the spelling of the assignee's corporate name from "Caterpillar Tractor Company" to --Caterpillar Tractor Co.--.

Signed and Sealed this tenth Day Of February 1976 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer (mnmissimwr oj'latents and Trademarks

Claims

1. A torque rise limiting governor for controlling the position of a fuel control member of an internal combustion engine, comprising; an annular collar slidably disposed on the fuel control member; spring means resiliently urging said collar and the fuel control member in a first direction for increasing delivery of fuel to the engine; a flyweight arrangement responsive to engine speed normally to counterbalance the bias of said spring means and operative to permit the spring means to move the collar and the fuel control member in said first direction when the engine speed decreases due to increased loading thereon; means for limiting movement of the fuel control member in said first direction establishing a maximum fuel delivery position of the fuel control member; and lever means pivotally attached to the collar and engagable with the fuel control member and said limiting means for pivoting about the limiting means to move the fuel control member in a second direction for decreasing delivery of fuel to the engine when the engine speed decreases due to increased loading thereon after the fuel control member reaches its maximum fuel delivery position.

2. The torque rise limiting governor of claim 1 wherein said lever means cooperates with said limiting means for limiting movement of the fuel control member in said first direction.

4. The torque rise limiting governor of claim 3 wherein said limiting means includes engagement means disposed between said collar and said lever means and being movable in said first direction in unison with the collar and the fuel control member until said limiting means engages said stop member, said lever member being disposed for pivoting about said engagement means to move the fuel control member in said second direction after said limiting means engages said stop member.

5. The torque rise limiting governor of claim 4 wherein said lever means includes a pair of levers pivotally secured to the collar diametrically opposite to each other and extending radially inwardly towards the fuel control member.

7. The torque rise limiting governor of claim 6 wherein said fuel member has an annular flange secured thereto and wherein said end wall has an opening formed therein with said fuel control member extending through said opening with said levers disposed between said flange and said end wall.