US2887998A

US2887998A - Engine governor

Info

Publication number: US2887998A
Authority: US
Inventors: Robert H Thorner
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-02-23
Filing date: 1956-02-23
Publication date: 1959-05-26
Anticipated expiration: 1976-05-26

Description

May 26, 1959 Filed Feb. 23. 1956 R. H. THORNER ENGINE GOVERNOR 2 Shes 11s-Sheet 1 INVENTOR.

@une (QAM,v

MAN/FOLD VACUUM- /NcHEs or ME/ecu/zy May 26, 1959 Filed Feb. 23. 1956 ENG/NE RPM Figa 4 R. H. 'rHoRNER ENGINE GOVERNOR Hapfpowf@ MAN/FOL D VACUUM- /Ncwss of MERCURY 2 Sheets-Sheet 2 2000 RPM /0 ZO 30 w 60 THRoTH' OPEN/NG -D6kss ENG/NE RPM fw. H

IN V EN TOR.

(Qua,

United States Patent ENGINE GOVERNOR Robert H. Thorner, Detroit, Mich.

Application February 23, 1956, Serial No. 567,270

31 Claims. (Cl. 123-103) The present invention relates to lgovernors for internal combustion engines, and more particularly to engine controlling governors operated by fluid pressure. The present'application is a continuation-impart of my `application Serial No. 59,109, tiled November 9, 1948,

entitled Engine Governor, now Patent No. 2,736,304.

One object of the present invention is to provide a governor for an internal combustion engine which is simple and of low cost since an engine speed-driven element is not required, and which provides better performance than present-day velocity governors. There is substantially no loss in r.p.m. when the engine is loaded, and there is no power loss because the governor throttle remains wide open until the governed speed is attained.

All governors at the present time are considered to be dangerous in traffic emergencies because the engine cannot be operated above the governed speed to avoid a serious accident if necessary. Another object of my invention is to provide a governor that includes means whereby the governor can be released by the driver while driving, to cause the governor throttle to snap to the wide-open position instantly.

Another object of this invention is to provide novel means'for compensating for the undesirable variation of engine vacuum with change in throttle position, so that the desirable variation in engine vacuum with change in engine speed is available to control the governor, and to accomplish such result without the use of costly pistons or the like.

Present velocity governors utilize the restricting eifect of an otfset throttle valve so that the air-forces produced on an offset buttery throttle cause the throttle to move against a spring resulting in an inherent loss of power. A furtherr object of this invention is to provide a novel vacuum governor including power operated throttle valve means so that the Velocity air-forces of the engine are not used to operate the throttle thereby preventing a power loss from this cause.

Still another object of the present invention. is to provide novel means for adjusting the governor to provide any desired speed-droop and for governing the engine at selectively diiferent engine speeds.

Briey stated, the present invention comprises the combination in a servo type vacuum governor, ofV an improved means to functionally integrate the operation of a pilot valve and an associated pressure (or vacuum) operated member with a mechanism arranged tocompensate for throttle vacuum. Ihe elements of the present invention are of such a nature and are so arranged in combination that the piston and its supporting parts used in the governor disclosed in my parent application are eliminated and are replaced with supporting mechanism that has been found to be economically and operatively superior.

These and. other objects which will appear more clearly as the speciiication proceeds, are accomplished, according to the present invention, by the arrangement and sains atented May 26, 1959 llC .the line 2-2 of Fig. l; Fig. 3 is a view partly in section, as along the line 3-3 inFig. l, showing an additional element of the pilot valve housing;

Fig. 4 is a chart showing typical variations of manifold vacuum with engine speed at various fixed throttle positions; g

Fig. 5 is a chart showing the same data as in Fig. 4, plotted to illustrate the variation fin manifold vacuum at various constant engine speeds as the throttle opening is varied; v y

Fig. 6 is a sectional view taken on line 6-6 in Fig. 1, showing one form of cam supporting means and associated adjustment features;

Fig.v 7 is an end elevation of the cam proper, as shown in Figs. 1 and 6;

Fig. 8 is a chart showing the characteristic performance of conventional governors and the improved performance of the present invention; y

Fig. 9 is a perspective view showing relatively sepat rated yparts including a portion of one of a pair of ilexible members forming a swingable support for the pilot valve assembly hereof; and

Fig. 10 is a schematic view similar to Fig. 1, ing a modified form of the present governor.

show- The term vacuum as used herein is to be intery preted as the difference between two absolute pressures; one pressure corresponding to the existing atmosphere and the other pressure being sub-atmospheric, and ac'- cordingly refers to the same physical state las though recited in terms of (absolute) pressure.

All vacuum and velocity governors now in commercial use utilize the manifold vacuum in the intake pasy lf engine vacuum is utilized as the engine speed signal, the problemssage of an internal combustion engine.

involved become extremely complex for reasons demonstrated below. Vacuum sensing governors differ in one important respect from :governors that utilize centrifugal ilyweight means to produce the sensing forces. Forvacuum governors at eac'h different position of the throttle a different functional' relationship of speed versus vacuum is available, 'whereas for centrifugal-force-v sensing governors the forces that vary with speed are substantially independent of variations in throttle position. Figs. 4 and 5 show a family of curves of a typical internal combustion engine illustrating the charl acteristics of manifold vacuum which may be varied by means of two factors, and hence may be considered as 'being comprised of two components as follows:

(l) The manifold vacuum may be varied by changing the engine speed at any fixed-throttle position; hence the manifold vacuum is responsive to changes in engine speed, the vacuum increasing as the engine speed increases. This component is herein referredto as speed vacuum.

(2) The manifold vacuum may be varied by changing the throttle position at constant speed, hence the manifold Vacuum is also responsive to changes in throttle position, the vacuum increasing as the throttle opening. de-f'` creases. 'This component is herein referred' to as throttle vacuum.

Fig. 4 shows a typical family of curves illustrating variations in values of the speed-vacuum which accompany changes of engine speed at various fixed positions of the throttle. The speed sensing forces which m-ust be used by any vacuum governor are functions of the minute changes in pressure which result from small changes in speed along each of the illustrated curves. As indicated by the decreasing slope of the various curves at the higher engine speeds, the pressure change per unit of speed hecomes progressively less, thus making it increasingly difficult for the speed sensing mechanism of any vacuum governor to be sufficiently sensitive at high engine speeds.

Fig. 5 shows typical curves (which may be plotted from data taken from Fig. 4) illustrating the variations of manifold vacuum as the throttle-opening is varied at different constant engine speeds, Which curves represent the throttle vacuum as above defined. In order to produce satisfactory speed regulation, suitable mechanism or means must be provided in a vacuum governor' to compensate for the effects of throttle-vacuum variation. The method of obtainng such satisfactory speed regulation with the present governor, in its illustrated forms, is in effect to extract from the intake manifold vacuum the pressures which vary as a function of engine speed (speedvacuum) for use as a speed-sensing force, and to compensate for the inherent variations in manifold vacuum which accompany changes in throttle position throttle vacuum).

Referring to Fig. l, a governor housing 1 is positioned between and sealed to a downdraft carburetor 2 and the engine intake manifold partially shown at 3. The form of the governor illustrated in Fig. l is of the sandwich type as opposed to the type of governor forming a built-in portion of the carburetor assembly, although either form may be used for the governor of the present invention. In the form shown, the governor controls the engine speed through operation of a governor throttle 4 which is separate from a carburetor throttle 5. In the built-in type, the governor throttle and carburetor throttle are one and the same. The throttle 4 is located on the downstream side of the carbuertor venturi 6 and the throttle 5 which is connected for operation by the driver through suitable and conventional accelerator linkage (not shown). Fuel is admitted to the air at the carburetor venturi throat 6 before the air reaches the throttle 5. In the arrangement shown, the engine speed is controlled by automatic operation of the governor throttle 4 only when the carburetor throttle 5 is opened sufficiently to allow the engine to exceed the governed speed. The throttle 4 is mounted on a suitable shaft 4a journalled in the housing 1 and actuated by a pressure responsive member such as a diaphragm 9 through a link 11 which operably connects the diaphragm with the throttle 4.

The present governor, as illustrated in Fig. l, includes a power amplifier having a uid bleed air flow circuit controlled by a pilot valve mechanism, generally indicated at 2t), arranged to modulate pressures acting on the power member (diaphragm 9 or its equivalent such as a piston or bellows) of the amplifier. In'the illustrated type of pressure modulation system at least two restrictions or orifices are required in series in the uid circuit, and the pilot valve is actuated by speed responsive means to vary the aperture of at least one of the orifices. In order to obtain a large range of pressure control for a given amount of pilot valve movement, the pilot valve in the form shown operates simultaneously to vary the apertures of both of the orifices. Although in the form of the invention illustrated in Fig. l air is used as the working liuid, any pressure uid such as oil for example, may be used. The present governor according to Fig. l has a single-acting servo-motor with a position type modulating pilot valve action, whereas the governor according to Fig. l() hereof (to be discussed) has a double-acting servo-motor with an excursion type modulating pilot valve action.

The fluid servo-motor, in the form illustrated in Fig. l, comprises a diaphragm 9 secured to housing 1 by a suitable cover to provide a chamber 13 on one side of the diaphragm and a chamber 15 on its other side. The chambers 15a and 15b defined by the housing walls are in open and unrestricted communication with chamber 15. In the above-mentioned circuit as shown by arrows, air from the carburetor entrance 17 liows through a conduit or passage 21, through an inlet orifice 23, through a chamber 25 which communicates with chamber 13 by means of a passage 27, through an outlet orice 29, through a chamber 31 and out through passage 33 to the intake manifold at 35. The passage 33 is sufficiently large that the pressure in chamber 31 is substantially the same as the pressure in the intake passage at 35 on the downstream side of the throttle. Thus, since negligible line-loss is produced by the passage 33, the chamber 3l in the form shown is subjected to the full vacuum in the manifold at 35. This large passage is also desirable for operation of the novel speed sensing member to be described, Furthermore, various other portions of the circuit including conduit 21 are large enough to minimize line-loss so that the pressure transmitted through chamber 15a to the inlet orifice 23 is substantially undiminished from that in the carburetor entrance 17.

The pressures in the above-described circuit (in charnber 25) transmitted to the diaphragm 9 for positioning thereof are controlled by a movable pilot valve element 37, hereinafter referred to as pilot-valve. In its preferred form, thc pilot valve has oppositely tapered valve faces 39 and 41 which are maintained in proper cooperative relationship to the orifices 23 and 29, respectively, by means to be described. The pressure in the chamber 2S is statically transmitted and hence is substantially equal to the pressure in chamber 13 at all times.

In some installations it may be necessary or desirable to damp the movements of diaphragm 9. In such cases a suitable damping means may be lprovided by a restriction 27a in passage 27. Such restriction, in the illustrated location which is optional, can serve another useful purpose to be discussed.

The movements of the pilot valve 37 in response to speed-changes causes the valve faces 39 and 41 gradually to reduce the effective aperture of one of the two orifices 23 and 29 and simultaneously to increase the effective aperture of the other orifice. In this manner the illustrated pilot valve 37 modulates the pressure in the chambers 25 and 13 to any value from the pressure at the entrance of orice 23 (same as at carburetor entrance 17) when the valve face 41 seats in orifice 29 to the value of pressure at the outlet off orifice 29 (unmodified manifold vacuum) when the valve face 39 seats in orifice 23. Thus the pilot valve in its travel between these two extreme positions can cause any pressure to be applied to diaphragm 9 between the abovementioned extreme values of pressure. The fluid-bleedcircuit as above described is provided for the purpose of pressure control. The actual quantitative amount of air which flows through the circuit is not important in itself but is incidental to the pressure-controlling function thereof. The flow of air may be minimized by properly sizing the pilot valve and its cooperating orifices to prevent lean idle mixtures and excessive idle speeds off the controlled engine, although the orifices must be large enough to permit suicient speed of response of diaphragm 9.

The diaphragm 9 is biased in a direction to oppose the pressure (vacuum) in chamber 13 by a suitable spring 43 secured at one end to the housing (in chamber 15a) and having its other end connected to the throttle 4 in a manner to urge the throttle toward its wide-openposition at which it is suitably stopped.

With the foregoing construction as described, any travel-position of the pilot valve 37 will produce corresponding but amplified travel-positions of the dia- KIN' phr'agm 9 and throttle 4, and the positioning of the diaphragm 9 is accomplished by changes in force exerted by the spring 43 in relation tothe vacuum in chamber 13.

The pilot valve 37, as shown, is supported for frictionless movementsby

leaf spring members

45 and 47 each of which is connected at one end thereof to the pilot valve 37 and at the other end to the valve housing 49 as shown inrdetail in Fig. 9. As shown in Fig. 9, each leaf spring has an elongated hole 153 or the equivalent to permit universal movement of the valve faces 39` and 41 when they are -alternately held against their seats 23 and 29, respectively, and the retaining screws 152 are tightened. The screws are inserted through their respective leaf springs into threads 154, and anti-torque members such as member 155, which may be pre-bent as shown to provide a lock-washer action, are inserted between the screw heads 152 and their

respective leaf springs

45 or 47. When the valve faces are alternately held against their seats to compensate for all eccentricity (regardless of production variations) and the corresponding locking screw is tightened, the torque of the screw is transmitted only to the anti-torque member which then contacts the surface 150 in rotary abutment. With this construction only thrust is transmitted to the leaf springs so they are maintained in their set position while the screw is being tightened.

When the pilot valve travels between its two extreme positions, it is subjected only to air contact and is env tirely free from the usual detrimental effects of static and kinetic friction. The present pilot valve is also entirely free from the adverse eiects usually encountered in sliding type pilot valves as a result of dirt and gum wedging between the close-fitting surfaces thereof. Thus the present pilot valve and its associated mechanism is capable of immediate response to extremely small forces applied axially'of the valve.

In the` specification and claims herein, as Well as in other patents of the applicant, the supporting leaf springs have been referred to as substantially frictionless. The leaf spring supports for the pilot valve actually are completely frictionless from a practical standpoint since in extensive tests of the pilot valve action by itself `when supported by leaf springs, no lag or hysteresis could be measured. Any intermolecular friction in the material itself can, of course, be disregarded since it is immeasurably small. But the term substantially has been used solely to recognize this minute intermolecular friction, although from a practical standpoint the leaf-springsupported pilot valve is in fact completely frictionless.

The pilot valve is actuated in response to changes in pressure in the intake manifold at (through passages 31 and 33) by a frictionless speed-sensing pressure sensitive member which comprises a circular (or other suitably shaped) disc 51 of small diameter secured to the pilot valve 37 and movable in relation to a cylinder 50 which may be formed `as a flange outstruck from a dischousing plate 53. Thus the disc is disposed in the aperture of the cylinder to comprise a movable portion of a wall of chamber 31. The disc 51 is mounted by suitable means as by soldering rigidly to a stem portion of the pilot valve 37, so that the disc, in the form shown,

is also supported by the

leaf springs

45 and 47 for fric- K tionless movements in relation to its cylinder 50. Such frictionless movements are made possible by providing substantially unirform perimetrical clearance between the cylinder and the disc, which clearance is maintained by the rigidity of the leaf springs in a direction transverse to the direction of movement of the disc. to the provisionof the perimetrical clearance, a negligible amount of air must continuouslybleed through the small clearance space (such as .004 in. diametrically) between the disc 51 and its cylinder 50 under the inuence of manifold vacuum. As illustrated, the ow of air through the branch air bleed past the disc 51 is from conduit 21, through passage 59, through chamber 15b,

Incident p through the clearance around the disc and into chamber'vv 31, where thebranchair bleed circuit joins the main portion of the uid bleed circuit, andthe combined airow passes .to the intake passage through conduit 33, which 'is v sufficiently large' tov vproduce negligible loss therein,vv asv previously discussed'. By providing this large unrestricted passage, the full unmodified vacuum in the intake manifold is applied to the disc despite the bleedf In order to provide a practical arrangement of the A disc as a frictionless sensing member, suitable means vare provided to permit Substantially concentric adjustment of the clearance space around the disc without the necessity'of maintaining close tolerances of the concentricity of the parts in production.v In the form shown a disc housing plate 53 is secured to the valve housing 49 by suitable means as by the screws 55, whereby the disc generally separates chamber 31 from chamber 15b. The plate 53 has holes 53a which are oversize in relation to the Shanks 55a of the screws 55 as shown partly in cross section 'in Fig. 3. With this construction the plate is adapted to be moved in various' directions in its principal plane before being secured in place by tightening the screws 55.` Such construction enables substantially concentric adjustment-of the'cylinder 50 in relation to the'disc 51 during assembly of the governor to provide a substantially uniform perimetrical clearance between the cylinder and the disc. A detachable cover 57 encloses the plate v`53 and disc 51, and an'opening 53h in the plate registers with a passage 59 invalve housing 49 to connect the chambers 15a and 15b for unrestricted flow of air.

The freely swingable or free floating support for the pilot valve provided bythe

leaf springs

45 and 47. and features thereof. to be described later` maintains the peripheral surface of the disc 51 out ofv contact with its cooperating cylinder 50V so that both the pilot valve and disc are completely free from restraining contact friction at all times.

Thus, the leaf spring supports provide not only for frictionless movement of the pilot valve, but serve to support without friction the `entire lspeed-sensing-mechanism. The sensing-mechanism may be defined herein as including all parts that must respondto the minute changes in vacuum that are produced by small changes in speed and comprise the pilot valve 37, the learf springs 45 and 47, the disc 51, the retainer 63, and the spring 61.

All claims directed to the frictionless leaf-spring supported pressure sensitive member (disc 51) and the combination thereof with the frictionless leaf-spring-supported valve member have been transferred to a copending application, Serial No. 754,736, filed August 13, 1958.

The forces acting axially on the pilot valve produced by iluid pressure on the disc -51 `are opposed by the force of a coil spring 61 mounted between the pilot valve and a throttle-vacuum compensating cam mechanism assembly 60 connected to move with the throttle 4. The spring 61, as shown, is supported at the valve end by a spring retainer 63 secured to the pilot valve 37 Ifor substantially frictionless movements therewith and at the other end by an adjustable spring retainer 65. The second spring retainer 65 is supported 'for movement approximately along the axis of the pilot valve by a swingable arm 67 having a fixed fulcrum provided as shown by a hinge pin 69 secured to the housing. The opposite free end of the larm 67 is pivotally secured to a yoke member 71 having a threaded stern portion 71a extending into complementary threads of the adjustable `retainer 65 (shown knurled to facilitate adjustment). The

swingable arm 67 and the yoke 71 and spring retainer 65 are secured together for free pivotal relative movement by a suitable connecting pin 73.

The spring 61 is supported in position at all times during governor operation by means of a slight preloading between its two

retainers

63 and 65, which pre loading occurs incident to the normal calibration of the device. The spring retainers illustrated in Fig. 1 have frusto-conical guide portions disposed to freely enter the spring ends for the support thereof. The spring 61 is adjusted for setting governor speed within a practical range (for a given contour of a cam 81 to be discussed) by turning the spring retainer 65 about its threaded connection with yoke 71.

The reset mechanism 60 is provided by the present invention to compensate for throttle-vacuum and includes a novel adjustment for speed-droop (speed-regulation). Referring to Figs. l, 6 and 7 the throttle shaft 4a carries a cam mounting block or member 75 which is shown in Fig. 6 secured to the shaft by a set screw 77. The link 11 of the diaphragm 9, as shown, is operatively connected to a plate 79 suitably rigid with the mounting block 75 and throttle shaft 4a. A bent portion 11a of the link 11 as shown in Fig. l extends through an opening in the plate 79. A hook 79a of the plate 79 is also shown in Fig. l as comprising a support for one end of the spring 43. A cam 81 which is shown in the form of a plate is apertured for support by the free end of the throttle shaft 4a (see Fig. 6) rfor rotational adjustment of the cam relative to the shaft. The cam 81 is secured to the mounting block 75 by a screw S3 projecting through an arcuate slot 85 of the cam into a threaded opening in block 75. Rotary adjustment of the cam through small increments is facilitated by a pin 87 rotatable in a socket or bore of the mounting block 75. Pin 87 has a relatively eccentric portion 87a of reduced diameter projecting through a slot 88 of the cam 81 shown as extending radially of the throttle shaft axis. The eccentric portion 87a is provided with a slot or its equivalent 8711 ttor engagement by a suitable adjusting tool. The angular position of the cam is adjusted by loosening the screw 83 and revolving the eccentric portion 87a which cooperates with the radial slot 88 to revolve the cam as required to give the desired speeddroop. The screw 33 is then tightened to lock the carri in the adjusted position.

The cam contour is represented in Figs. l and 7 by the curved surface contour portion 81a of the cam 81 and is disposed for operative contact with the swingable arm 67 either directly with the arm or through a suitable camfollower wheel or roller 67a mounted on the arm 67, as on a pin 73. The contour portion 81a is developed to vary the biasing force of the spring 61 acting on the pilot valve in accordance with the various positions of the throttle 4. Assuming proper calibration of the cam contour 81a, the biasing force of the spring 61 which opposes the forces produced by vacuum on the disc 51 increases and decreases as a function of the increase and decrease of throttle vacuum which accompanies throttle closing and opening movements, respectively. Y

The left end of the spring 61 as viewed in Fig. l 1s in effect supported solely by the pilot valve 37 which, together with the disc 51 (also mounted on the pilot valve), is guided for free-floating movement by the supporting

leaf springs

45 and 47. Thus, none of the speedsensing-elements of the governor are subjected to restraint by static or kinetic friction. The speed sensing elements of the governor speed-sensing mechanism as previously dened exclude the adjustable spring retainer 65 since it does not move in response to speed changes as will be shown.

Operation The governor mechanism as above-described operates as follows: Assume that an automotive engine is under stable operation controlled by the governor wherein the throttle i would be in substantially a fixed position. lf the engine load decreases as when the vehicle descends a hill, such change in loadV and resulting increase in engine speed produces a speed change signal in the form of an increase in vacuum in the intake manifold at 35 and chamber 31 acting on the disc 51 to effect movement of the pilot valve 37 to the right las viewed in Fig. 1. Such speed-effected movement of the pilot valve 37 produces an increase in the vacuum in chamber 13 which initiates movement of the throttle 4 towards its closed position and tends to restore the governed speed.

Such movement of the throttle 4 toward closed position as a result of increased engine speed from the initial assumed fixed-throttle position produces an increase in throttle-vacuum as illustrated in Fig.'5. Without compensation, the increased throttle vacuum acting on the disc 51 would produce further movement of the disc and pilot valve rightwardly which would transmit more vacuum to the diaphragm 9 which, in turn, would apply still more throttle vacuum to the disc until the throttle 4 completely closes.

Such detrimental effects of the throttle vacuum are compensated by the cam mechanism 6) above described. As the throttle 4 is rotated in a closing direction (clockwise), the cam 81 is revolved therewith; this movement of the cam acts to increase the effective force of the spring 61 acting on the disc 51 (transmitted through the pilot valve 37) sufficiently to compensate for or balance the increased force produced on the disc 51 by the increased vacuum which accompanies movements of the throttle in restoring the governed speed. The contour 81a of the cam S1 can be profiled in effect to balance at all positions of the throttle such forces produced by throttlevacuum acting on the disc, whereby movements of the disc are substantially responsive to changes in manifold vacuum that accompany changes in engine speed (speed vaeuum) lt is apparent from the foregoing that during |any stable condition, the initial change of speed detected by the governor speed-sensing-mechanism (51, 37, 61 ete), incident to a change in load occurs at substantially a tixed-throttle-position; and as the throttle is moved to maintain the desired governed speed at the new load, the cam operates in effect to render the disc 51 substantially insensitive to the pressure changes acting on the disc which accompany such changes in throttle position. When the engine load is increased, as when the vehicle ascends a hill, the actions of the governor are exactly the reverse of those described above.

In actual operation entirely from a mechanical or physical standpoint, the arm 67,

retainer assembly

71, 65 and spring 61 might be considered as a connecting link or a shaft. Considered only from this mechanical or physical aspect, it might be said that the cam S1 acts to position the pilot valve 37 by means of a connecting shaft whose length varies with speed-vacuum and throttle-vacuum. Considered in this manner, the valveend of the spring would be subjected to speed-sensing movements, whereas the cam-end of the spring would be subjected to movements to compensate for throttle vacuum or load changes.

Consider the governor action with the cam 81 calibrated for a given engine speed in an automotive vehicle when the engine is accelerated from idle operation by fully depressing the accelerator. As the speed increases along the wide-open-throttle power curve M--D-R-N in Fig. 8, (to be discussed), the speed-vacuum acting on the disc 51 increases along the corresponding wide-openthrottle vacuum curve in Fig. 4. When the speedvacuum is sufficient to move the disc 51 and pilot valve 37 to the right in opposition to the force of the spring 61, as determined by cam 81 and the adjustment of retainer 65, the throttle is caused to start movement in a closing direction. As the throttle moves further towards a closed position, if the openating load produced by the speed produces excess speed-vacuum on the disc to elect a further closing of the throttle, which is accompanied by cam compensation for throttle-vacuum as above described. If, at this new throttle position, the speed produced thereby again exceeds the governed speed, the throttle similarly will seek a further closed position. This procedure continues until the throttle position is such as to produce the calibrated governed speed at the existing engine load, at which time the governor is stabilized. Any changes of engine load in either direction produce small deviations of engine speed which, in turn, produce small changes in speed-vacuum acting on the disc to effect small speed-restoring movements of the throttle. The entire foregoing governor cut-in procedure following wideopen-throttle acceleration and the subsequent stabilizing |action occurs extremely fast in actual automatic operation of they governor in seeking a balance at the operating" load of the engine.

In the operation of the present governor as shown in Fig. 1, if the cam 81 were calibrated to compensate comf Secondly, and veryimportant, the angular positioning means for the .cam servesto provide an excellent speeddroop adjustment. Before :considering the problem of speed-droop control, refer torFig. 8 which shows a curve -of horsepower versus engine speed at wide-open-throttle. The curve- Ef-C'repres'ents regulation of atypical'velocity governor as compared toV isochronous operation such as illustrated by the curve D-C. With a velocity governor,:'as the vengine is loaded fromno-load at C to fullload at E aspeed-droop is vproduced corresponding to C-V which can be as much as 500 rpm. or more, for example, and a power'loss occursA such as represented by distance P in Fig. 8; IThecam of the present governor can beproled to producea loadingV curve having a speed droop Vvas illustrated by the curve B-W. With such a calibration, if the cam 81 is'revolved slightly in relation pletely for the throttle-vacuum at the governed speed,

the travel of the pilot valve 37 would be responsive substantially'solely to engine speed. Under these conditions, the pilot valve would :assume a new position with each small change in speed because the changing force of the spring 43 which opposes movement of the diaphragm 9 necessitates a correspondingly changing vacuum in chamber 13 to move the throttle 4 throughout its travel. Under .l

these conditions, this changing vacuum in chamber 13 can only be produced by a gradual displacement of the pilot-valve which must be produced by small changes of engine speed (speed droop) as the engine load varies from full-load to no-load.

Furthermore the present governor shown in Fig. 1 has a servo-motor (diaphragm 9) biased by a spring 43 in which only one chamber of the servomotor is controlled by pilot valve 37 which modulates the pressures acting on the servo-motor. With such a construction in this assumed condition (which would be equivalent `to having the pilot valve operated by a force varying substantially solely as a function of speed independent of the throttle position), a slightly different engine speed is required during governor operation for each position of the throttle as the load is varied from no-load to full-load, whereby the governor inherently would produce a speed droop. Hence this form of the present governor provides a position type pilot-valveaction rather than an excursion type pilot-valve-action, which will be discussed in reference to Fig. l0. As explained above, the governor would then inherently produce a speed-droop as shown by the curve D-W, Fig. 8, again assuming that the cam is calibrated to compensate entirely for throttle-vacuum at the governed speed.

Governor adjustment considerations The angular adjustment of the cam 81 in relation to the throttle shaft 4a is provided for several reasons. Firstly, it can be seen in Fig. that the variation in vacuum with throttle position increases at a very high rate with small change in throttle movement toward closed position, particularly between and 20 degrees. Since the contour of each cam reects the shape of one of the curves shown in Fig. 5, the angular relationship between the cam and the throttle 4 is important. If, in production, the cam were secured to the throttle in fixed angular relationship, any slight production variations could produce inconsistent operation of one governor in relation to another having the same design and intended cam calibration. Such production variations have no detrimental effects in the present governor since the angular position of the cam may be set as required in each governor unit.

to the throttle shaft 4a in' a counterclockwise direction by the eccentric 87a, the isochronous curve D-C shown in Fig. 8 may be approached-or"attained.- However, in another method of controlling speed droop the governor may be calibratedto provideA substantially zero speed droop or isochronous operation by contouring the cam as required whereby adjustmentof the cam 81 in a clockwise direction will cause the governor to operate with any desired speed droop. Such angular movement of the cam would, in elect, cause the isochronous loading curve D-C 4to swing as though hinged at D whereby point C is moved rightwardly to give a curve similar to D-W.

As described previously, the speed of the engine controlled by the governor may be set by `rotary adjustment of the spring retainer 65. In view of the fact that the cam 81 as illustrated in Fig. 1 reflects the contour of a singlevt"hrottlevacuum curve as shown in Fig. 5, and since the curves shown in Fig. S are, not parallel, only a limited range of governed speeds is obtainable by adjustment of the `seat member 65 when a single cam contour is used. Accordingly, in order `to provide satisfactory regulation over allarge range of engine speeds, as from 1600 r.p.m. to 3800 r.p.m. for example, the governor can be furnished witl1-a plurality of cams for selective use. As an alternative, the cam contours corresponding to various throttle vacuum curves (as in Fig. 5) can beprovided ,on a single suitably adjustable three dimension. cam as shown in my copending patent application, Serial. No. 59,109 (now Patent Number 2,736,304).

Emergency speed mechanism Another feature of the present invention is illustrated in Figs. 7 and 8. Referring to Fig. 7, if the cam 81 shown therein is calibrated'to provide substantially isochronous operationl (including ull-loadoperation as indicated at D of curve M-D-C in Fig. 8), the contour of the cam correspondingv to full load would be approximately'as illustrated by the dotted line 81b in Fig. 7. If governors so calibrated are used on automotive engines they may be dangerous in traic emergencies because, if necessary, the engine cannot be operated above the governed speed to avoid an accident. Accordingly, thepresent governor optionally waybe arranged to permit the governed speed to be exceeded to a predetermined value only while accelerating. v

This result is accomplished by providing a portion 81C in the cam surfacey Slaat or near its wide-open-throttle section, which portion 81e has larger radii than the radii of the corresponding cam surface portion 81b. The difference Ain radii is greatly exaggerated in Fig. 7 for clarity. Such cam portion 81e` acts through the biasing for the `highspeed feature during acceleration may be -f lll accelerated from a speed less than the governed `speed to the calibrated high speed, whereupon the governor would cut-in rapidly and move the throttle to the operating engine load at a reduced speed.

Thus in the operation of the vehicle at a speed less than the governed speed, if the driver rapidly depresses the accelerator (which with its linkage is the driver control means, not shown) to full-throttle position and holds it there, the governor throttle 4 will automatically be moved rapidly toward its wide-open-position. This action occurs lbecause the speed-vacuum acting on the disc 51 is less at the assumed starting speed (lower than the governed speed) than the speed-vacuum corresponding to the governed speed. For engines having a built-in carburetor-governor combination, the drivers control means ((accelerator) is arranged to override the governor action for controlling all engine speeds less than the governed speeds, all in a manner well known to those skilled in the art of governors.

Under conditions usually encountered in such traine emergencies as mentioned above, the abrupt movement of the throttle to wide-open position will enable the engine speed to increase, as along the curve M-D-RN to A, Fig. 8, which increases the speed-vacuum acting on the disc 51 until the vacuum is sufficient to overpower the spring 61 and start the pilot valve movement toward closed position. The throttle continues to close further toward the final stable road-load condition under the inuence of speed-vacuum as already described under the heading Operationf whereby the cam is revolved with the throttle by the diaphragm 9 until the cam follower 67a is, in effect, moved from the cam portion 81C to 81a. As a result the engine speed is reduced from the speed at A in Fig. S to the speed at B, whereby in effect, the cam portion produces a reverse speed-droop which occurs only during a very small part of the operating load range.

Thus, with the governor arranged as just above described and installed on an automotive vehicle governed at 50 m.p.h., for example, when the operator desires to pass a second vehicle traveling at 47 mph., he rapidly depresses and maintains the accelerator in the wide-open throttle position. His vehicle will then accelerate from 47 m.p.h. to the excess passing speed calibrated for example at 60 mph. After the vehicle attains this higher speed, the governor causes the speed to reduce to the cruising value of 50 mph., which is still 3 m.p.h. faster than the assumed speed of the second vehicle. It is significant that although the governor throttle is automatically returned fairly rapidly from this excess-speed position to its' cruising position, the inertia of the vehicle produces a slow reduction of speed from 60 m.p.h. to 50 m.p.h. Thus, instead of slowly passing the other vehicle at a differential of only 3 mph. during the entire passing operation as with a conventional governor, an initial speed differential of i3 m.p.h. is provided and diminishingly retained to facilitate safe and rapid passing.

In applying this concept to governor types other than vacuum governors as disclosed herein, a cam may be used in cooperation with the engine control means, or merely a link may be used since a cam as applied herein is nothing more than a variable link. Also, while some automatic transmissions exhibit small degrees of slippage, for all practical purposes vehicle speed and engine speed are directly related. Therefore, when the terminology in the claims of this case recite this principle and other principles disclosed herein in terms of engine speed, it should be understood that vehicle speed and engine speed are to be interpreted synonymously in construing the invention defined by these claims.

Emergency release Governors used on automotive vehicles, as already discussed above, may be dangerous in `traffic emergencies. When such emergencies occur, accidents may be avoided if the driver can manually inactivate the governor and operate his vehicle above the lgoverned speed. The governor release device 30 hereof, as shown in Fig. l, comprises a cup-shaped fitting 32 adapted to be mounted on the vehicle instrument panel or in any other position within easy reach of the driver, or at the governor itself for remote control of the release by means of a flexible pull wire or the like. The fitting 32 is formed to provide a hollow chamber 34 which can be connected by a suitable tube 34a to the conduit 27 between the chamber 25 and the chamber 13.

The chamber 34 is normally closed and held by a seal plug 35 of soft metal or other suitable material which fractures readily, and a release ring 36a is attached to the disc. A shield 36h, as shown, is interposed between the ring 36a and the plug 36 to prevent the driver from tampering `with the plug.

When the governor release device 30 is installed in the vehicle, the restriction 27a of control conduit 27 is located between the connection of tube 34a with conduit 27 and the pilot valve chamber 25. ln operation, when the ring 36a is pulled out by the driver, the seal plug 36 is broken and the diaphragm chamber 13 is thereby placed in open communication with the atmosphere through the tube 34a. An advantage of the restriction 27a (with respect to the emergency release system) is to make it impossible for vacuum from the pilot valve mechanism to overpower the force of the diaphragm spring 43, whereby the throttle is moved by the spring to wide-openposition. Thus, when the seal is broken by the driver, the throttle instantly may be moved to the wide/openposition. The release device 3G is in effect a quick opening valve, and any such valving means may be used as the equivalent of the device 30.

After a broken seal is noted upon routine inspection, the seal assembly is suitably restored to its original condition as by replacing the plug 36 and the governor will ythen operate normally. The practical utility of the emergency release device is made apparent when it is considered that the supervisor of a iieet of trucks can, for example, keep a record of the broken seals of each driver, and the drivers can then be allowed a definite number of broken seals per year before being penalized. The above remarks concerning road speed and engine speed as being synonymous for claim interpretation also apply to claims directed to the emergency release concept.

Double acting servo-mechanism Fig. l0 illustrates basically the same system and construction as shown in Fig. l, differing therefrom principally in that the servomotor is double acting in response to fiuid pressure differential and with appropriate modifications of the pilot valve mechanism for such action. Thus the diaphragm 9a under control of the pilot valve mechanism is subjected to pressure (vacuum) for move ment in both directions without the use of spring return, whereby the vacuum in chamber 102 performs the equivalent function of the diaphragm return spring 43 of the form shown in Fig. l. Chamber 104 is sealed at thc link 11 by a flexible bellows-type seal 106 of small area. The pilot valve assembly 103, as shown, is constructed similarly to the corresponding assembly 20 of Fig. l except that twice the number of valve orifices and enacting movable valve elements are provided to modulate oppositely the pressures in the two diaphragm chambers 162 and 104 through passages 110 and 112, respectively.

The air iiow or control circuit of Fig. l0 in effect includes two branch circuits, each similar to the circuits described in relation to Fig. l, arranged in parallel branch. Each of the two parallel circuits include an inlet valve or variable restriction at orifices 114 and 116, respectively, exposed to the atmosphere and an outlet variable restriction at orifices 118 and 120, respectively, opening into a chamber 124 which communicatesy with the manifold vacuum through passage 33 as shown. The

13` pilot yvalve 122 includes the four illustrated tapered valve faces for modulating-control of the apertures of oriiices 116 and 118 while oppositely and simultaneously con-V trolling the apertures of the orices 120 and 114.

In operation, as the pilot valve is moved to the leftv 81 of mechanism 128 to provide the ydesired compensa--v tion for throttle-vacuum acting on the disc. When the engine speed decreases the valve movement and all opv erations initiated thereby in the governorare the reverse.

of those just above described. t v l The pilot valve of the form of the governor shown in Fig. 10 was referred to earlier herein as an excursion type valve mechanism as compared to the position type valve mechanism of Fig. 1 in which the pilot-valve 37 assumes different travel-positions as the load `is varied throughout the load range during .governor operation, assuming full compensation for throttle vacuum. If the contour of the cam 81 of the governor shown in Fig. 10 were calibrated to compensate exactly forvthe change in throttle-vacuum at the. governed speed, then the travel of the pilot valve would kbe-responsive substantially only to engine speed. Since in the arrangement of. Fig. l0 the diaphragm 9a is actuated solely by changes in pressure on opposite sides thereof, thediaphragm would continue to move if the pilot valve is moved and maintained at a distance from its mid-position. Hence in order to provide a stable governor, the pilot valve must operate by intermittent excursions from substantially its 1.

The valve must return after eachsuch can only remain in this one neutral position at one engine speed bacause the biasing force of the spring 126 varies slightly as the pilot valve moves. Since, as assumed, the stable condition of the governorcorresponds to substantially a single position of the pilot valve and hence only one force of the spring 126, isochronous or near isochronous governorA operation can be obtained.

I wish it understood that my invention isnot limited to any specic construction, arrangement or lfori-n of the parts, as it is capable of numerous modications and changes without departing from the spirit of the claims.

What I'claim is:

l. In a governor for controlling the speed of an internal combustion engine having an intake passage for the ilow of air therethrough in which the pressure varies as a result of a change in position of a throttle in said passage and also as a result of a change in engine speed at fixed positions of said throttle, the improvement com prising the combination of a governor throttle in said intake passage, a pressure responsive member operatively connected to said throttle for actuation thereof, a fluid circuit having a ow of fluid therethrough communicating with said pressure responsive member, valve means in said fluid circuit to control pressure therein acting on said pressure responsive member -to effect movement thereof, a second pressure responsive member communicating with and responsive to pressures in said intake passage, said second pressure responsive member acting on said valve means to eifect movement thereof in response to changes in intake passage pressure at xed positions of said throttle, spring means having one end acting on said valve means to oppose the forces of said second pressure responsive member, movable means conin intake passage pressure acting on said second pressure responsive member resulting from changes in the position of said throttle, said valve means beingso arranged in relation to said circuit that during all governor operatf ing conditions any change of engine speed produces movement of said valve means to effec-t a corresponding movement of said first-named pressure responsive member always ina direction tending to restore the governed engine speed, and swingable means having one vend connected by hinge means to a Xed support and its other endconnected to support said opposite spring end.

2. In a governor for controlling the speed of anV internal combustion engine having an intake passage for the ilow of air therethrough in which the pressure varies as a result of a change in position ofv a throttle in said passage and also as a result of a change in engine speed at tixed positions of said throttle, the improvement comprising the combination of a governor throttle in said intake passage, a pressure responsive member operatively connected to said throttle for actuation thereof, a fluid circuit having a flow of fluid therethrough communicating with said pressure responsive member, valve means in said fluid circuit to control pressure therein acting on said pressure responsive member to elfect movement thereof,

a second pressure responsive member communicating with and responsive to pressure in said intake passage, sald y second pressure responsive member acting on said valve n means to effect movement thereof in response to changes in intake passage pressure at fixed positions of said throttle, spring means having one end acting on said valve means to oppose the forces of said second pressure responsive member, movable means including a cam having a contoured portion operatively connected to said governor throttle and operating to position the opposite end` of said spring means to increase its force as a function of the closing movements of said throttle-to compensate for the decrease of intake passage pressure acting on said second pressure responsive member resulting from said closing movements of'said throttle, and conversely, said valve means being so arranged in relation to said circuit that during all governor operating conditions any change of engine speed produces movement of said valvepmeans to effect a corresponding movement of said first-named pressure responsive member always in a direction tending to restore the governed engine speed, swingable means having one end connected by hinge means to a xed support and its other end connected to support said opposite spring end, said other end of for providing in governor operation a predetermined relationship between said throttle and said opposite spring end to produce said compensation. v

3. In a governor for an engine having means to control the speed thereof, the combination of a pressure responsive member operatively connected to said` control means for actuation thereof, a fluid circuit having a ow of fluid therethrough and communicating with said pressure responsive member, valve means in said circuit to control pressure therein acting on said pressure responsive member to effect movement thereof, sensing means responsive to changes in engine speed actingon said valve means `to eifect movement thereof and corresponding movements of said pressure responsive member also in response to changes in engine speed, spring means having one end acting on said valve means to oppose the forces of said sensing means, movable means operatively con-` ernor operating conditions any change of engine speed produces movement of said valve means to effect a corresponding movement of said pressure responsive member always in a direction tending to restore the governed engine speed, and swingable means having one end operatively connected to a fixed support and its other end operatively connected to support said opposite spring end.

4. In a governor device for limiting the maximum speed of an automotive vehicle including an engine, comprising, control means including driver operated means for regulating the speed of the engine, said control means including means responsive to changes in engine speed to effect speed-restoring movements of said control means, cam means operatively connected to said control means and arranged to act on said speed responsive means for maintaining within a predetermined variation a calibrated cruising vehicle speed at all positions of said control means corresponding only to part-load operation, said cam means having a portion to produce a calibrated vehicle speed appreciably higher than said cruising speed at all positions of said control means corresponding only to loads at or near full load operation, whereby the vehicle will accelerate toward said higher speed starting from a speed less than said cruising speed while the driver-operated means is maintained in substantially its full-load position whereupon the governor automatically causes the speed to reduce to said cruising speed after said higher speed is attained.

5. In a governor device for limiting the maximum speed of an engine mounted in an automotive vehicle, driveroperated means, governor operated control means for regulating the speed of the engine, comprising in combination, mechanism operatively connected to said governor operated control means for actuation thereof, said mechanism including sensing means responsive to changes in engine speed to eifect speed-restoring movements of said control means for maintaining within a predetermined variation a calibrated cruising engine speed at those positions of said control means corresponding only to partload operation, and means enabling operation of the engine at a calibrated engine speed appreciably higher than said cruising engine speed at positions of said governor operated control means corresponding only to loads at or near full load operation, said elements and means being so arranged that the vehicle Will accelerate toward said higher engine speed starting from a speed less than said cruising speed while the driver-operated means is maintained in substantially its full-load position whereupon the governor automatically can cause the engine speed to reduce to said cruising speed after said higher speed is attained.

6. In a self-regulating automatic control mechanism for automatically controlling a variable condition, the combination of, control means to regulate said controlled condition, a pressure responsive member operatively connected to said control means for actuation thereof, a fluid circuit having a ow of fluid therethrough and communicating with said pressure responsive member, valve means in said fluid circuit for directing fluid therein to said pressure responsive member for effecting movements thereof in response to movements of said valve means, sensing means responsive to changes in said controlled condition and acting on said valve means to effect movements thereof for producing movements of said pressure responsive member with amplified forces for moving said control means for maintaining within a predetermined variation a desired value of said controlled condition, and movable means operatively connected to said control means for controlling forces acting on said valve means in accordance With the movement of said control means to control said variation of the desired value of said controlled condition, said movable means including a cam and supporting means therefor, said cam being arranged to revolve about said supporting means for angular movement in relation thereto and controlling said forces acting on said valve means, and means for revolving the cam about said supporting means to regulate the amount of said controlled variation of the desired value of said controlled condition produced by the control mechanism.

7, The combination of elements defined in claim 6 and said revolving means includes rotatable eccentric means arranged to produce said relative angular movement.

8. In a governor for an automotive engine having means to control the speed thereof, comprising a pressure responsive member operatively connected to said control means for actuation thereof, biasing means opposing the force of said pressure responsive member and tending to move said control means to its full-load position, a uid circuit for the flow of fluid therethrough communicating with said pressure responsive member, valve means in said circuit to control pressures therein acting on said pressure responsive member to effect movement thereof in response to movements of said valve means, sensing means responsive to changes in engine speed acting on said valve means to effect movement thereof and corresponding movements of said pressure responsive member and said control means in a direction tending to maintain the governed speed, sealed emergency means communicating with said pressure in the portion of said circuitacting on said pressure responsive member and containing said last named pressure, and governor release means operable substantially instantaneously to open said circuit portion to a pressure sufliciently different from said pressure-responsive member pressure to alter same suticiently that said biasing means moves said control means substantially instantaneously to its full-load position.

9. In a governor for an internal combustion engine having an intake passage for the flow of air therethrough, a governor throttle operatively mounted within said passage to control the speed of the engine, a pressure responsive member operatively connected to said throttle for actuation thereof, a circuit having a flow of fluid therethrough and communicating with said pressure responsive member, valve means in said circuit to control pressure therein acting on said pressure responsive member to effect speed controlling movements thereof in response to movements of said valve means, a second pressure responsive member acting on said valve means and communicating with said intake passage to effect speed-controlling movements of said valve means in response to changes of intake passage pressure at fixed position-s of said throttle, and movable means operatively associated with said throttle and adapted to produce forces acting on said valve means and varying in accordance with positions of said throttle to compensate for changes of intake passage pressures resulting from movements of the throttle to accommodate changes in engine load, said valve means including a movable valve member, and substantially frictionless swingable means imparting rigidity in one direction acting to support said valve member for substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve lmember suspended within the fluid controlled thereby to prevent surface contact of said valve member other than fluid contact during said operational movements thereof, whereby said speed controlling movements of said valve means are substantially instantaneous and consistent in responding to said changes in intake passage pressure at xed throttle positions.

10. In a governor for automatically controlling the speed of an engine having an air intake passage, comprising, control means for regulating the speed of the engine, a pressure responsive member operatively connected to said control means for actuation thereof, an air circuit connected to said intake passage to cause a tiow of air therethrough and communicating with said pressure responsive member, valve means in said air circuit for directing air therein to said pressure responsive member to effect movements thereof in response to movements of said valve means, said valve means including a movable valve member, substantially frictionless swingable means imparting rigidity in one direction acting to support said valve member for substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve member suspended within the fluid controlled thereby to prevent surface contact of said valve member other than uid contact during operational movements thereof, substantially frictionless movable sensing means responsive to changes in engine speed and providing sources acting on said supported valve member to eiect movements thereof for producing movements of said pressure responsive member with amplified forces for moving said control means, substantially frictionless biasing means opposing the forces produced by said sensing means, said supported valve member and said sensing means and said biasing means being so arranged that cooperative speed-responsive movements thereof are substantially frictionless and thereby respond substantially instantaneously and consistently to minute changes in the forces produced by changes in engine speed acting on said sensing means to effect speed controlling movements of said control means.

ll. The combination of elements defined in claim l0, and means operated by said control means for controlling forces acting on said supported valve member and varying in accordance with the movements of said control means.

l2. In a governor for automatically controlling the speed of an internal combustion engine having an air intake passage and a throttle therein for regulating en gine speed by controlling air ow through said passage and in which passage a vacuum is produced on the downstream side of the throttle, comprising, a pressure responsive member operatively connected to said control means for actuation thereof, an air circuit connected to said intake passage on the downstream side of the throttle to cause a flow of air through the circuit under the influence of intake passage vacuum and communicating with said pressure responsive member, valve means in said air circuit for controlling vacuum therein acting on said pressure responsive member to effect movements thereof in response to movements of said valve means, said valve means including a movable valve member, substantially frictionless swingable means imparting rigidity in one direction acting to support said valve member for -substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve member suspended within the fluid controlled thereby to prevent surface contact of said valve member other than iiuid contact during said operational movements thereof, substantially frictionless movable sensing means responsive to changes in engine speed and acting tovprovide forces acting on said supported valve member to effect movements thereof for producing movements of said pressure responsive member With amplified forces for moving said control means, substantially frictionless biasing means opposing the forces produced by said sensing means, said supported valve member and said sensing means and said biasing means being so arranged that cooperative speed-responsive movements thereof are substantially frictionless and thereby respond substantially instantaneously and consistently to minute changes in the forces produced by changes in engine speed acting on said sensing means to effect speed controlling movements of said control means.

13. The combination of elements defined in claim 12, and variable force second biasing means acting on said pressureresponsive member to oppose the forces produced thereon by air pressures in said circuit acting on said pressure responsive member, the force of said second vbiasing means varying as a function of the movement of Isaid pressure responsivemember, said valve means controlling pressures on onlyfone side of said pressure responsive member, the conguration of said movable valve member in relation to other elements of said valve means being such as to produce modulated air .pressures acting on said one side of said pressure responsive member to effect movement thereof as a function of the movement of said supported valve member, and the force of said frictionless biasing means varying as a function of the movement of said supported valve member, and means including means operatively connected to said control means for controlling forces acting on said supported valve member and varying in accordance with the movements of said control means.

14. ln a self-regulating control mechanism for automatically controlling a variable condition comprising in combination, control means to regulate said variable condition, a pressure responsive member operatively connected to said control means for actuation thereof, two fluid circuits each having inlet and outlet restrictions therein for the flow of fluid therethrough, said pressure responsive member communicating on one side thereof with one of said fluid circuits between said two restrictions therein, said member communicating on the other side thereof with the other of said two fluid circuits between said two restrictions therein, valve means including at least one valve member to modulate the restricting eiect of at least one of said restrictions in each of said two fluid circuits for controlling pressures in said two circuits acting on said pressure responsive member to effect movement thereof in response `to movements of said valve means, frictionless lswingable leaf spring means imparting rigidity in one direction acting to support said valve member for 'substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve member suspended within the fluid controlled thereby to -prevent surface contact of said supported valve member other than fluid contact during operational movements thereof, substantially frictionless movable sensing means responsive to changes in said controlled condition and acting to provide forces acting on said supported valve member to effect movements thereof for producing movements of said pressure responsive member with amplified forces for moving said control means, substantially frictionless biasing means opposing the forces produced bysaid sensing means, said supported valve member and said movable sensing means and said biasing means being so arranged that cooperative movements thereof are substantially frictionless and thereby respond substantially instantaneously and `consistently to minute changes in the forces produced by changes in said controlled condition acting on said sensing means to effect movements of said control means.

l5. In a self regulating control mechanism for automatically controlling a variable conditioncomprising in combination, control means to regulate said controlled condition, a pressure responsive member operatively connected to said control means, a circuit having a flow of `fluid therethrough and communicating with said pressure responsive member, valve means including a movable valve member in said circuit to direct fluid therein to said pressure responsive member for actuation thereof, substantially frictionless swingable means imparting rigidity in one direction acting to support said valve member for substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve member suspended 'within the uid controlled thereby to prevent surface contact of said valve member other than fluid contact during operational movements thereof, and movable sensing means responsive to changes in said controlled condition to actuate said valve member for effecting regulating movements of said control means, and means operatively connected to said control means for controlling forces acting on said valve member and varying in accordance with the assises movements of `said control means to control the variation of the desired value of said controlled condition.

16. ln a self-regulating control mechanism for automatically controlling a variable condition the combination of, control means to regulate said controlled condition, a pressure responsive member operatively connected to said control means for actuation thereof, a fluid circuit having a source of fluid pressure to cause a iiow of iiuid therethrough and communicating with said pressure responsive member, valve means in said iiuid circuit for controlling pressure therein acting on said pressure responsive member for effecting movements thereof, said valve means including a first valve member and a mating valve member cooperable therewith, substantially frictionless swingable means imparting rigidity in one direction acting to support one of said valve members for substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve member suspended within the fluid controlled thereby to prevent surface contact of said supported valve member other than fluid contact during operational movements thereof, substantially frictionless movable sensing means responsive to changes in said controlled condition and acting to provide forces acting on said supported valve member to eifect movements thereof for producing movements of said pressure responsive member with amplified forces for moving said control means, substantially frictionless biasing means opposing the forces produced by said sensing means, said supported valve member and said sensing means and said biasing means being so arranged that cooperative movements thereof are substantially frictionless and thereby respond substantially instantaneously and consistently to minute changes in the forces produced by changes in said controlled condition acting on said sensing means to eect movement of said control means for maintaining within a predetermined variation a desired value of said controlled condition, and means operatively connected to said control means for controlling forces acting on said supported valve member and varying in accordance with the movements of said control means to control the variation of the desired value of said controlled condition.

17. The combination of elements dei-ined in claim 16, in which said swingable means comprises a pair of spaced substantially parallel leaf spring members.

18. The combination of means defined in claim 16, and variable force second biasing means acting on said pressure responsive member to oppose the forces produced thereon by fluid pressures in said fluid circuit acting on said pressure responsive member, the force of said second biasing means varying as a function of the movement of said pressure responsive member, said valve means controlling pressures on only one side of said pressure responsive member, the configuration of said supported valve member in relation to the said other valve member being such as to produce modulated pressures acting on said one side of said pressure responsive member to effect movement thereof as a function of the movement of said `supported valve member, and the force of said frictionless biasing means varying as a function of the movement of said supported valve member, whereby the movement of said supported valve member varies as a function of said controlled condition to effect corresponding movement of said control means also as a function of said controlled condition.

19. The combination of elements defined in claim .16, and said fluid circuit including two parallel branch circuits, said pressure responsive member communicating on one side thereof with one of said branch circuits and on the other side thereof with the other of said branch circuits, and said supported valve member controlling pressures acting on opposite sides of said pressure responsive member to effect said movements thereof and said control means.

20. The combination of elements defined in claim 16,

2@ in which said means operatively connected to said control means includes means acting on said biasing means to vary the force thereof in accordance with the movements of said control means.

2l. The combination of elements defined in claim 16, in which said swingable means includes leaf spring means, and in which the force of said frictionless biasing means varies as a function of the movement of said supported valve member, and variable force second biasing means acting on said pressure responsive member to oppose the forces produced thereon by uid pressures in said uid circuit acting on said pressure responsive member, the force of said second biasing means varying as a function of the movement of said pressure responsive member, said valve means controlling pressures on only one side of said pressure responsive member, said circuit including two restrictions therein, said communication of said circuit with said pressure responsive member on said one side thereof being at a point between said two restrictions, and said supported valve member being shaped to modulate the restrictive effect of at least one of said restrictions to effect controlled-condition-regulating movements of said pressure responsive member and said control means as a function of the movements of said supported valve member.

22. The combination of elements defined in claim` 16, and the force of said frictionless biasing means varying as a function of the movement of said supported valve member, and variable force second biasing means acting on said pressure responsive member to oppose the forces produced thereon by uid pressures in said circuit acting on said pressure responsive member, the force of said second biasing means varying as a function of the movement of said pressure responsive member, said valve means controlling pressures on only one side of said pressure responsive member, the configuration of said supported valve member in relation to the other said valve member being such as to produce modulated pressures acting on said one side of said pressure responsive member to effect movement thereof as a function of the movement of said supported valve member, and said means for controlling forces acting on said supported valve member including a cam having a contour to provide any desired predetermined variation of said last named forces as a function of the movements of said control means.

23. The combination of elements defined in claim 16, and the force of said frictionless biasing means varying as a function of the movement of said supported valve member, and variable force second biasing means acting on said pressure responsive member to oppose the forces produced thereon by fluid pressures in said circuit acting on said pressure responsive member, the force of said second biasing means varying as a function of the movement of said pressure responsive member, said valve means controlling pressures on only one 'side of said pressure responsive member, the configuration 0f said supported valve member in relation to the other said valve member being such as to produce modulated pressures acting on said one side of said pressure responsive member to effect movement thereof as a function of the movement of said supported valve member, and said frictionless biasing means including a spring acting on said supported valve member, and said means for controlling forces acting on said supported valve member including means acting on said spring to vary its force in accordance with movements of said control means.

24. ln a governor device for limiting the maximum speed of an automotive vehicle including an engine, comprising, control means including driver operated means for regulating the speed of the engine, means including means responsive to changes in engine speed to effect speed-restoring movements of said control means, means including means operatively connected to said control means and arranged to act on said speed responsive E:21 means when said control means is at' or near its fullload position toproduce a predetermined vehicle speed appreciably higher than the cruising speed regulated by the governor at all other load-positions of said control means, said elements and means being so arranged that the vehicle will accelerate toward said higher governed speed starting from a speed less than said cruising speed While thel driver operated means is maintained in substantially its 4full-load position whereupon the governor automatically can ycause the governed speed to reduce to said cruising speed after said higher speed is attained.

25. In a governor device for limiting the maximum speed of a component of an automotive vehicle including an engine, comprising, control means including driver operated means for regulating the speed of said component, means including means responsive to changes in the speed of said component to effect speed-restoring movements of said control means, means including means arranged to act on said speed responsive means when said control means is at or near its full-load position to produce a predetermined speed of said component appreciably higher than the cruising speed thereof regulated by the governor at all other load-positions of said control means, said elements and means being so arranged that the vehicle will accelerate toward said higher governed speed starting from a speed less than said cruising speed while the driver-operated means is maintained in substantially its full-load position whereupon the governor automatically can cause the governed speed to reduce to said crusing speed after said higher speed is attained.

26. In a governor device for limiting the maximum speed of an automotive vehicle including an engine, comprising, control means including driver-operated means for regulating the speed of the engine, a pressure respon'sive member operatively connected to said control means for actuation thereof, a uid circuit having a flow of fluid therethrough and communicating with said pressure responsive member, valve means in said circuit to control pressure therein acting on -said pressure responsive member to effect movements thereof in response to movements of said valve means, sensing means responsive to changes in engine speed acting on said valve means to effect movements thereof and corresponding movements of said pressure responsive member, means acting on said valve means to produce a calibrated vehicle speed appreciably higher than said cruising speed at all positions of said control means corresponding only to loads at or near full load operation, said elements and means being so arranged that the vehicle will accelerate toward said higher governed speed starting from a speed less than said cruising speed while the driver operated means is maintained in substantially its full load position Whereupon the governor automatically causes the governed speed to reduce to said cruising speed after said higner speed is attained.

27. The combination of elements defined in claim 25, in which said means acting on said speed-responsive means is operatively connected to said control means to be operated thereby for producing forces on said speedresponsive means effecting said higher engine speed.

28. The combination of means defined in claim 12 in which said movable sensing means comprises a second pressure responsive member subjected to a fluid pressure that varies as a function of engine speed to effect movements of said movable valve member in response to changes in said fluid pressure.

29. The combination of elements defined in claim 12, wherein said swingable means comprises at least one leaf spring mem-ber, and variable force second biasing means acting on said pressure responsive member to oppose the forces produced thereon by fluid pressures in said fluid circuit acting on said pressure responsive member, the force of said second biasing means varying as `a. function of the movement of said pressure responsive member; said vvalve means controlling pressures on only one side of 'said pressure responsive member, the configuration 'of said movable valve member-in relation to other lelements of said valve means being such as to produce modulated pressures acting on said one side of said pressure responsive member to effect movement thereof as a function of the movement of said supported valve member, and the forceof said frictionless biasing means varying as a function of the movement of said 'supported'valveme'rnben whereby the movement of said supported valve member varies as1 a function of engine speed to effect corresponding movement of said throttle also as'a function of engine speed. v

30. In a control device to operate a movable controlled member in response to changes in a variable condition, comprising, a pressure responsive member operatively connected to said movable controlled member for actuation thereof, a fluid circuit having a ow of fluid therethrough and communicating with both sides of said pressure responsive member, valve means including a movable valve member in said circuit to control pressures therein acting on said both sides of said member, movements of said valve member increasing the pressure on one side of said pressure responsive member while decreasing the pressure on the other side thereof, and conversely to effect movements of said pressure responsive member in response to movements of said valve means, frictionless swingable means imparting rigidity in one direction acting to support said valve member for substantially frictionless movements in a direction transverse to said first-named direction by maintaining said Valve member suspended within the fluid controlled thereby to prevent surface contact of said supported valve member other than fluid contact during operational movements thereof, substantially frictionless movable sensing means responsive to `changes in said Variable condition and exerting forces on said supported valve member to effect movements thereof as a function of said Variable condition, and substantially frictionless biasing means to oppose said forces, said supported valve member and said sensing means and said biasing means being so arranged that cooperative movements thereof are substantially frictionless and thereby respond to minute changes in said variable condition to effect movement of said controlled member.

31. In a governor for automatically controlling the speed of an engine comprising in combination, control means to regulate the speed of the engine, a pressure responsive member operatively connected to said control means for actuation thereof, a fluid circuit having a source of fluid pressure to cause a ow of fluid therethrough and communicating with said pressure responsive member, valve means including a movable valve member in said fluid circuit for directing fluid therein to said pressure responsive member to effect movement thereof, substanially frictionless swingable leaf spring means having width imparting rigidity in one `direction acting to support said movable valve member for substantially frictionless movements in a direction transverse to said first-named direction by maintaining said valve member suspended within the uid controlled thereby to prevent surface contact of said supported valve member other than fluid contact during operational movements thereof, substantially frictionless movable sensing means responsive to changes in engine speed and acting on said supported valve member to effect movements thereof for producing movements of said pressure responsive member with amplified forces for movements of said control means, substantially frictionless biasing means opposing the forces produced by said sensing means, whereby the cooperative movements of said supported valve member, said movable sensing means, and said biasing means are substantially frictionless and thereby respond substantially instantaneously and consistently to minute changes in the forces produced by changes in engine speed acting on said sensing means agences to elect speed-controlling movements of said control means for maintaining within a predetermined variation a desired value of engine speed, and means including means operatively connected to said control means for controlling forces acting on said movable valve member and varying in accordance with the movements of said control means to control said variation of the desired value of engine speed.

References Cited in the le of this patent UNITED STATES PATENTS 2.4 Sehossow Apr. '6, 1926 Nettleton Nov. 8, 1932 Udale Apr. 6, 1942 Greenland Mar. 30, 1948 Dulong Sept. 20, 1949 Branson Feb. 5, 1952 Thorner June 1, 1954 Cook et al Sept. 20, 1955 Thorner Feb. 28, 1956 Thorner Mar. 6, 1956 Thorner Oct. 1, 1957