US2984112A

US2984112A - Engine governor with stabilizing means

Info

Publication number: US2984112A
Application number: US806146A
Authority: US
Inventors: John H Parks
Original assignee: Caterpillar Tractor Co
Current assignee: Caterpillar Inc
Priority date: 1959-04-13
Filing date: 1959-04-13
Publication date: 1961-05-16
Anticipated expiration: 1978-05-16

Description

May 16, 1961 J. H. PARKS ENGINE GOVERNOR WITH STABILIZING MEANS Filed April 13, 1959 I ll`llllll 4 m ,I l 102237, l

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VIIIIIIIIIIIIIIII s, .M mm m4,. mm m J A ORNEYS ,Y j. l ..z,svs4,11z 1 fENGnsn oovinieronA wrrn s'rAjBIuzlNc A John i .'Co., Peoria, Ill., a 'corporation of 'California Filed Apr.' 13,1- 1959; ser. N9. 806,146

. 2' (Cms-sez) This invention relates to governors and particularly to a governor having means to dampen or prevent erratic or surging operation which may be induced by harmonic or sympathetic vibrator'y motion of engine and governor parts under certain speed conditions.

In tractors and other engine driven vehicles or equipment, it is often found that a governor set for a certain speed will occasionally produce a surge or momentary increase of speed of the engine which is controlled thereby creating an undesirable and sometimes dangerous condition as for example when the tractor is approaching another vehicle or load to be pushed and the momentary increase of speed produces an unanticipated force at impact.

It is the object of the present invention to provide a governor which through very simple and inexpensive means prevents such undesirable surging without interfering with the normal function of the governor and the conventional loading or changing the tension of the main governor spring.

A further object of the invention is to provide a governor with means las described above effective to prevent rapid or uncontrolled adjustment of the spring tension in either direction.

Further and more specic objects and advantages of the invention are made apparent in the following specilication wherein reference is made to the accompanying drawing in which a preferred form of the invention is shown.

In the drawing:

Fig. 1 is a vertical sectional view through a governor embodying the present invention illustrating its connecltion with fuel control means of an internal combustion engine, and

Fig. 2 is an enlarged fragmentary view partially in section of a portion of the damping means of the governor illustrated in Fig. 1.

A conventional governor housing 10 is shown in Fig. 1 as secured to a fuel pump housing 11 where one of the fuel pumps '12 of an internal combustion engine, not shown, is illustrated. The fuel pump 12, for purposes of illustration is of the type -in which axial adjustment of its plunger shown at 13 varies its eiective stroke and thereby the volume of fuel injected into the engine. The plunger is conventionally adjusted through a gear 14 and rack bar 15 meshing therewith and adapted to slide in an axial direction in response to movement of the governor to which it is connected by a link 16 and bellcrank 17.

The governor comprises a spindle 18 rotatable at a speed proportional to engine speed through the medium of gearing, not shown, by which it is connected to a moving part of the engine. The spindle carries a pair of ily-weights 19 pivoted as at 20 to brackets on the spindle and having anti-friction rollers 21 which engage beneath a collar or spring riser, generally indicated at 22, including a thrust bearing 23 and a seat 24 for the governor main spring shown at 25. A spring seat 26 for the H. Parks, reina, 111.,.assrgn'r to caterpillar Tractor 2 opposite en d ,of the governor spring is slidably mounted on a trunnion 27 and is adjustable by a yoke 28 which cooperates withl a collar groove 29 formed in the seat and is controlled by a lever 30 which is connected by means not shown lto a governor control lever disposed rat a convenient location outside the governor housing.

Through the conventional' governor thus far described, kadesired engine4 speed is obtained by varying the-force V'applied to the spring 25 through the adjustable spring seat 26. Due, however, to unpredictable forces in some cases ascribed to harmonic vibratoryvconditions, changes 'occur in the position of the governor flyweght 19 accelerating or` de clerating Ithe engine unexpectedly.

The present invention insures against such unexpected changes in engine speed or surges by providing a hydraulic damping means to resist quick action of the spring riser 22. The spring riser has a central bore to provide a sliding fit on the spindle A18 and the spindle is provided ywith an axial oil passage 31 communicating with a passage 312 in the housing which in turn communicates with a source of oil under pressure, not shown, such for example as the lubricating oil system of the engine itself. The passage 31 in the spindle is closed as by a Iplug 31a at its upper end and, as best shown in Fig. 2, a radial passage 33 communicates with a space between the outside diameter of the spindle and the inside diameter of the riser 22 to communicate oil under pressure to a chamber 35 formed by the upper end of the bore in the riser. A baie 36 closes the upper end of its chamber where itis pressed against a shoulder 37 somewhat below the top of the spring riser to provide a small reservoir 38 at its upper end. A small orifice 40 is provided in the baille 36 and limits the rate at which oil may pass through the baille between the reservoirs 35 and 38. Consequently when there is a tendency toward surging or any rapid adjustment of engine speed through vertical movement of the riser on the spindle, the action is damped because of the restricting oriiice 40. Upon any tendency to'ward rapid downward movement of the riser, oil in the reservoir 35 is forced upwardly through the orifice 40. Upon rapid upward movement of the riser, oil in the reservoir 38 is drawn downwardly through the oriiice 40 as :indicated by the arrow in Fig. 2. In order to insure that oil will be drawn downwardly and that the reservoir 35 is not illed as rapidly yas the riser moves upwardly, the flow of oil into the reservoir 35 is purposely limited by the space between the reduced upper end of the spindle and the bore of the riser which in practice is 'a clearance of about 4-6 thousandths of an inch. The excess oil constantly ilowing through the reservoirs spills over the top of the reservoir 38 serves to lubricate the moving parts of the governor and returns by gravity to the lubrication system of the engine through conventional channels.

I claim:

l. In combination with a governor having a vertically disposed rotatable spindle carrying ilyweights, a riser slidable on Ithe spindle adjacent the upper end thereof and urged in one direction by the llyweights and in the opposite direction by a governor spring, means to damp sudden motion of the riser which comprises a cylindrical extension thereon projecting upwardly beyond the top of the spindle, and a bale with -a restricted oriiice in said extension intermediate the top of the spindle and the top of the extension to form two lluid chambers between which fluid must iiow through said restricted orice upon relative vertical movement of the riser Iand spindle, and means to direct oil under pressure upwardly through the spindle to enter the lower of said chambers and pass through said orifice to the upper of said chambers and overilow the upper end of the extension on said riser.

2. In combination with a governor having a vertically disposed rotatable spindle carrying lyweig'hts, a riser slidable on the spindle adjacent the upper end thereof and urged in one -direction by the flyweights and in the opposite direction by a governor spring, means to damp sudden motion of the riser which comprises a cylindrical extension thereon projecting upwardly beyond the top of the spindle, and a bale with 'a restricted orice in said extension intermediate the top of the spindle and the top of theextension to form two fluid chambers between which fluid must flow through said restricted orifice upon relative vertical movement of the riser and spindle, means to direct oil under pressure upwardly through the spindle to enter the lower of said chambers and pass through said oriiice to the upper of said chambers and overow the upper end of the extension on said riser, and means to restrict the ow of oil into said lower chamber 4 v to a rate that will insure downward flow through the restricted orifice when Vthe riser moves upwardly suddenly with respect to the spindle.

References Cited in the le of this patent UNITED STATES PATENTS 1,104,119 Horning Y July 21, 1914 1,265,883 Church May 14, 1918 2,141,541 Levy Dec. 27, 1938 2,607,578 Slonneger a Aug. 19, 1952 2,653,020 Stinson s u Sept. 22, 1953 2,719,611 Previnquieres Oct. 4, 1955 FOREIGN PATENTS 73,092 Austria Feb. 10, 1917 20,231 Great Britain May 27, 1915 177,386 Great Britain Mar. 30, 1922