US2910055A - Engine governor actuator - Google Patents

Description

Oct. 27, 1959 F. J. MARSEE ENGINE GOVERNOR ACTUATOR Filed Jan. 13, 1958 2 sheets sheet 2 INVENTOR.

FR E I BY Patented Oct. 27, 1959 This invention relates generally to engine governors, and more specifically to improved means for actuating such governors.

In certain cases where it was desirable to limit the speed of an engine using carbureting means, it has become the practice to employ vacuum actuated governors. However, it has been found diflicult and costly to produce a vacuum actuated governor which has a low r.p.m. spread and at the same time does not have a tendency to surge. This problem has been magnified in the recent past by the fact that the automotive industry is using a continually increasing percentage of multiple barrel carburetors. Because of this trend, the available vacuum is diminished and the resulting forces become insufiicient'for proper control of the governor. I

The general objective of this invention is therefore to provide improved means for actuating the governor which will provide a very low r.p.m. spread and will operate without surging.

Another object of the invention is to provide a means for actuating the governor which, though responsive to manifold vacuum as a control, is not dependent on a supply of vacuum as a means of transmitting governor operating power.

It is a further object to provide agovernor actuator mechanism which is responsive to varying manifold vacuum as an indicium of varying engine speed, and in which a fluid impeller or impellers varying in their output pressure in response to variable engine speed are employed to set up a control or valve-operating pressure differential, under which differential a governor throttle is operated.

Yet another object is to provide a governor actuator of the above sort which, though responsive to engine manifold vacuum as a control, is independent of the change in manifold vacuum occasioned by a change in vehicle road load.

A still further object is to provide an impeller type governor actuator as described which is equally applicable to engines supplied with fuel by either a carburetor or pressure fuel system.

The foregoing as well as other objects will become more apparent as this description proceeds, especially when considered in connection with the accompanying drawing illustrating preferred embodiments of the invention, wherein:

Fig. 1 is a view in axial section through an actuator mechanism according-to one basic embodiment of the invention.

Fig. 2 is a similar schematic view of a modification;

Fig. 3 is a fragmentary sectional detail of an alternative form of liquid return provision; and

Figs. 4 and 5 are views in plan and axial section, respectively, of a production embodiment of the invention.

Referring first to Fig. 1 of the drawings, a housing for the mechanism is formed which is comprised of two sections 10 and 12, within the respective cylindrical cavities 14 and 16 of which impeller blades 18 and 20 are mounted on an impeller shaft 22. Shaft 22 is driven by suitable means at some constant ratio to the engine speed. A supply tank 24 furnishes hydraulic fluid to the system through a conduit 26 which communicates with a housing intake passage 28. Passage 28 is in communication with an annular cavity 30 surrounding shaft 22, which cavity supplies the liquid to an axially. extending conduit 32 in the shaft through a series of radial shaft ports 34.

Radial conduits 36 are formed within the blading of impeller 18, in direct alignment with further radial ports 38 of the impeller shaft 22, which communicate with the axial conduit 32, as well as the cylindrical impeller cavity 14 of housing section 10. p

A pressure responsive diaphragm assembly 40 is located on the housing section 12, being comprised of a diaphragm 42 held securely at its margin between the housing section 12 and an exterior cap 44; a tapered flow control valve pin 46 centrally secured to the diaphragm; and a spring 48 is mounted between the diaphragm 42 and the cap 44, and normally biases the diaphragm and valve 46 downward. V

A conduit 50 communicates a source of manifold vacuum with a chamber 52 between the diaphragm 42 and the exterior cap 44; and a further conduit 54 leads from theouter diameter of the cylindrical cavity 14 to a chamber 56 formed between the diaphragm and housing 12. The diameter of tapered flow control valve 46 is such as to allow a small percentage of fluid, variable in accordance with its insertion in conduit 54, to pass around it when the valve 46 is introduced into the vertical portion of conduit 54.

A third conduit 58 leads from the chamber 56, communicating with an axially formed conduit 60 in impeller shaft 22, aswell as with a chamber 62 of second diaphragm assembly 64. Radially formed conduits 66 in the blading of the second impeller 20 communicate with conduit 58 between the impeller cavity 16 and the axial shaft conduit 60, being in alignment with radially formed ports 68 in impeller shaft 22. A still further conduit 70 leads from the outer diameter of cylindrical cavity 16 to a chamber 72 between the diaphragm 74 of assembly 64 and housing section12.

Diaphragm assembly 64 further comprises an exterior cap 76 clamping diaphragm 74 to housing section 12', and a valve stem 78 suitably connected to the last named diaphragm. The exterior cap 76 contains an inner passage or conduit 80 which is controlled by a conical valve 82 mountedon the valve stem 78. A chamber 84 within the cap 76 and a tubular fitting 86 threaded therein receive the valve 82, as well as a spring 88 which causes the valve 82to be normally biased to the left. A hollow externally threaded adjustment screw 90, provided with a spring pad 92, is threaded in fitting 86 to enable the spring force on valve 82 to be adjusted.

A conduit 94 leads from chamber 84, communicating with a chamber 98 of a third governor diaphragm assembly 96. The diaphragm assembly 96 comprises a diaphragm 100 held securely between housing sections 102 and 104, a rod 106 (which controls the position of governor throttle valve 107) suitably connected to the diaphragm, and a spring 108 mounted about rod 106 and between housing section 104 and diaphragm. 100 so as to cause the diaphragm to be normally biased to to the left. The section 104 has a vent 110 communicating with the atmosphere anda space or chamber 112 between the sameand diaphragm 100. A liquid equalizer tube or return conduit 114, which leads from chamber 98 and communicates with the supply tank 24, is provided with an internal flow resisting restriction 116. v

-In order to best describe the operation. of the embodiment of Fig. 1, it should be assumed that a desired governed engine speed is 2800 rpm, under fiat-roadload conditions, and that the output pressure of each pump at 2800 rpm. engine speed is 7.0 lbs, per square inch, and, say, 3.0 lbs. per sq. inch at a speed at 1400 rpm.

When the engine is operating at this speed of approximately 1400 rpm, the throttle valves are still relatively closed, and because of this the manifold vacuum is still relatively high. This manifold vacuum causes the diaphragm 42 to raise against the force of spring 48 and in turn raise the flow control valve 46, with an effect to be discussed later. Let it be assumed that the valve 46 is lifted sutficiently to entirely clear the conduit 54. The pressure in conduits 54, 58, 60 and 68 will at this time be the output pressure of the impeller 18, or the assumed 3.0 lbs. per square inch. The liquid enters impeller 20 through ports 68 and is raised in pressure to a value of 6.0 lbs. per square inch, i.e., output pressure of 3.0 lbs. per square inch plus the incoming pressure of 3.0 lbs. per square inch.

This output pressure of 6.0 lbs. per square inch is communicated through conduit 70 to chamber 72 of diaphragm assembly 64, while the 3.0 lbs. per square inch output pressure of impeller 18 is transmitted to the chamber 62 on the other side of the diaphragm 74, which results in a pressure differential of 3.0 lbs. per square inch across the diaphragm 74. Now if spring 88 is so adjusted that a pressure differential of, say, 6.5 lbs. per square inch is required to open valve 82, then no fluid will pass by the valve 82 and into chamber 98 of the governor diaphragm assembly 96.

Now assuming that the engine speed is increased to 2800 rpm. At this time, the manifold vacuum has diminished, which results in diaphragm 42 of assembly 40 being moved downward by spring 48. This in turn causes the preferably tapered flow control valve 46 to move downward into conduit 54 to increase the restriction to flow in conduit 54.

Having assumed the output pressure of impeller 18 to be 7.0 lbs. per square inch. let is be further assumed that the pressure drop across the valve 46 is now 2 lbs. per square inch when there is flow through the system. Therefore the pressure in conduits 58, 60 and 68 will be substantially equal to the new output pressure of impeller 18 minus the pressure drop, or 5.0 lbs. per square inch in this case. The fluid then enters impeller 20 and is raised in pressure to a value of 12.0 lbs. per square inch, this being the sum of its output pressure 7.0 lbs. per square inch plus the incoming pressure of 5.0 lbs. per square inch.

This output pressure of 12.0 lbs. per square inch is then transmitted to chamber 72 of diaphragm assembly 64. While the incoming pressure of 5.0 lbs. per sonare inch is transmitted to chamber 62 on the other side of the diaphragm 74. with a pressure differential of 7.0 lbs. per square inch across the diaphragm 64. Since the spring 88 is adiusted so that a pressure differential of only 6.5 lbs. per square inch is reouired to open valve 82. then it can readilv be seen that the governor diaphragm was actuated a little before 2800 r.p.m. engine speed was reached and has now, because of the increase in pre sure. positioned itself so that the engine is sufiicientlv throttled by governor valve 107 to maintain the desired 2800 r.p.m.

The engine having obtained its governed speed. now assume that the road load is decreased. Because of this. the manifold vacuum rises again, and when the manifold vacuum rises, it reduces the pressure drop across the valve 46. However, this reduction in pressure drop does not in any wav change the pressure differential across the diaphragm 74, and the latter will not change its position. Therefore, it can be seen that for any one governed speed the load conditions and manifold vacuum may vary Without any change in governor position. This is true because the differential across the diaphragm 74 is constant for any one speed.

Fig. 2 of the drawings depicts a modified embodiment of the invention, the operation of which is the same as that of Fig. 1 except that it is primarily designed for use in conjunction with pressure fuel systems, that is, those fuel systems which deliver pressurized fuel at higher pressures proportional to engine speed. Hence elements shown in Fig. 2 which are either similar or identical to those in Fig. 1, are identified with the same numbers. This pressurized fuel is delivered to a conduit 55, the function of which corersponds to that of the conduit 54 in Fig. 1, and the resulting operation from that point is identical to that of Fig. 1. It is seen that the initial pressurization of the fuel, using the fuel as the pressure liquid, eliminates the need for the primary impeller 18 employed in the gravity supplied hydraulic system of Fig. 1.

Fig. 3 shows a modification in detail of the mechanisms of either Fig. 1 or Fig. 2 in which a secondary diaphragm assembly is employed, whose function is that of the assembly 64 of Figs. 1 and 2. Assembly 120 has a liquid return passage 122 to the supply tank, corresponding in function to the conduit 114 of Figs. 1 and 2, formed in a housing section 124 of the diaphragm assembly 64. This section affords a chamber receiving the valve connected to the diaphragm of the assembly. Passage 122 communicates with the diaphragm chamber through a restriction 126, and in all other respects the assemblies 120 and 64 are identical. Accordingly, corresponding reference numerals are employed to designate corresponding parts and further explanation is dispensed with.

Of course, when the modified feature of Fig. 3 is employed the return conduit shown in Figs. 1 and 2 is not used, there being no flow through chamber 98.

Figs. 4 and 5 show a production embodiment of the invention of the type of Fig. 1; and those elements which correspond to those in Fig. 1 are identified by like numbers.

The drawing and the foregoing specification constitute a description of the improved engine governor actuator in such full,'clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What I claim as my invention is:

1. An actuator mechanism for operative connection to an automotive or like engine governor characterized by a mechanically movable governor element, said mechanism comprising a fluid impeller device having means to drive the same at a speed corresponding to the speed of operation of an engine to be governed, a source of operating fluid connected in supplying relation to said impeller device for an increase in the pressure of said fluid by said device in accordance with the speed of operation of said device, a pressure responsive unit having first passage means for the communication of the same with said fluid source and the intake of said impeller device and second passage means for the communication of the same with the discharge of said impeller device, respectively, and provided with a pressure responsive member movable in response to pressure differential in said respective passage means, a valve connected to said member for movement thereby, a pressure responsive governor actuator unit adapted to be operatively connected to said movable governor element and having a conduit controlled by said valve for communication with one of said passage means, said actuator unit being responsive to variations in pressure in said conduit occasioned by movement of said valve, a further valve member controlling flow of fluid in the other of said passage means to occasion a variable pressure drop in the last named passage in accordance with the position of said last named valve member, and means responsive to variations in manifold vacuum to govern the position of said last named valve member.

2. An actuator mechanism for operative connection to an automotive or like engine governor characterized by a mechanically movable governor element, said mechanism comprising a fluid impeller device having means to drive the same at a speed corresponding to the speed of operation of an engine to be governed, a source of operating fluid connected in supplying relation to said impeller device for an increase in the pressure of said fluid by said device in accordance with the speed of operation of said device, a pressure responsive unit having first passage means for the communication of the same with said fluid source and the intake of said impeller device and second passage means for the communication of the same with the discharge of said impeller device, respectively, and provided with a pressure responsive member movable in response to pressure differential in said respective passage means, a valve connected to said member for movement thereby, a pressure responsive governor actuator unit adapted to be operatively connected to said movable governor element and having a conduit controlled by said valve for communication with said first passage means, said actuator unit being responsive to variations in pressure in said conduit occasioned by movement of said valve, a further valve member controlling flow of fluid in said first passage means to occasion a variable pressure drop in the last named passage means in accordance withthe position of said last named valve member, and means responsive to variations in manifold vacuum to govern the position of said last named valve member.

3. An actuator mechanism for operative connection to an automotive or like engine governor characterized by a mechanically movable governor element, said mechanism comprising an impeller device having means to drive the same at a speed corresponding to the speed of operation of an engine to be governed, a source of hydraulic operating liquid connected in supplying relation to said impeller device for an increase in the pres.- sure of said liquid by said device in accordance with the speed of operation of said device, said source comprising a supply of said liquid and a further impeller device having its intake connected to said supply, a pressure responsive unit having liquid passages arranged to connect the same respectively with said impeller devices, including first passage means to connect said unit with the discharge side of said further impeller device and with the intake of said first named device, and second passage means to connect the same with the discharge side of said first named device, said pressure responsive unit being provided with a pressure responsive member movable in response to pressure diflerential in said respective passage means, a valve connected to said member for movement thereby, a pressure responsive governor actuator unit having a liquid conduit controlled by said valve in regard to communication with one of said passage means, said actuator unit having means to operatively connect the same to said movable governor element, and being responsive to variations in pressure in said conduit occasioned by movement of said valve, a further valve member controlling flow of liquid in one of said passage means to occasion a variable pressure drop therein in accordance with the position of said further valve membet, and means responsive to variations in manifold vacuum to govern the position of said last named valve member.

4. An actuator mechanism for operative connection to an automotive or like engine governor characterized by a mechanically movable governor element, said mechanism comprising an impeller device having means to drive the same at a speed corresponding to the speed of operation of an engine to be governed, a source of pressurized liquid fuel connected in supplying relation to said impeller device for an increase in the pressure of said fuel by said device in accordance with the speed of operation of said device, a pressure responsive unit having first fuel passage means to connect the same with said pressurized source and the intake side of said impeller device and second passage means to connect the same to the discharge side of said impeller device, said pressure responsive unit being provided with a pressure responsive member movable in response to pressure differential in said respective passage means, a valve connected to said member for movement thereby, a pressure responsive governor actuator unit having a liquid conduit controlled by said valve in regard to communication With one of said passage means, said actuator unit having means to operatively connect the same to said movable governor element, and being responsive to variations in pressure in said conduit occasioned by movement of said valve, a further valve member controlling flow of liquid in one of said passage means to occasion a variable pressure drop therein in accordance with the position of said further valve member, and means responsive to variations in manifold vacuum to govern the position of said last named valve member.

5. An actuator mechanism for an automotive engine governor, comprising a liquid impeller device driven at a speed corresponding to engine speed, said device having means to connect the same to a source of operating fluid and acting to discharge said fluid at a substantially increased pressure, a first pressure responsive unit connected by a passage to said fluid source and the intake side of said impeller device and having a first valve element operated to control the flow of fluid through said passage, means to connect said unit for operation of said valve element in response to varying engine manifold vacuum, to thereby impose varying resistance to flow of fluid through said passage, a second fluid responsive unit including a chamber in communication with the output of said impeller device, a chamber adapted to communicate with the passage controlled by said first valve element, a pressure responsive member separating said chambers, and a second'valve element connected to'said pressure responsive member, said second chamber having a discharge opening controlled by said second valve element, and a third pressure responsive unit having means to operatively connect the same with said governor, said third pressure responsive unit being responsive to the discharge of fluid from said second chamber of said second unit under the control of said second valve element.

6. An actuator mechanism in accordance with claim 5, in which said source comprises a second impeller device having provision to connect its intake with asupply of the liquid, the discharge of said second impeller device being connected with the intake of the first named impeller device.

7. An actuator mechanism in accordance with claim 5, in which said source comprises a second impeller device, also driven in accordance with engine speed, having provision to connect its intake with a supply of the liquid, the discharge of said second impeller device being connected with the intake of the first named impeller device.

8. An actuator mechanism in accordance with claim 5, in which said source comprises a second impeller device, also driven in accordance with engine speed, having provision to connect its intake with a supply of the liquid, the discharge of said second impeller device being con nected through said passage with the intake of the first named impeller device.

9. An actuator mechanism in accordance with claim 5, in which said operating fluid is liquid engine fuel and said source comprises a .device for pressurizing said fuel having its discharge connected through said passage with the intake of said impeller device.

References Cited in the file of this patent UNITED STATES PATENTS 2,402,332 Lee .Tune 18, 1946 2,410,774 Chandler NOV. 5, 1946 2,419,171 Simpson et al. Apr. 15, 1947 2,438,663 Greenland Mar.'30, 1948 2,502,997 Schnaible Apr. 4, 1950 2,566,012 Winkler et a1. Aug. 28, 1951

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