US3612015A - Hydraulic valve control system - Google Patents

Abstract

A variable control mechanism for regulating the length of time and amount of opening of an engine valve during each cycle of operation. The control mechanism includes a closed hydraulic circuit or system including a reciprocal slave cylinder, a reciprocal master cylinder, and control means, which control the allocation of fluid volume within the hydraulic circuit so as to regulate the movement of the slave cylinders. The control means are adjustable so that the amount of regulation can likewise be adjusted.

Description

United States Patent Louis A. Hausknecht [72] Inventor 4504 State Road, Cleveland, Ohio 44101 [21] Appl. No. 21,098 [22] Filed Mar. 19, 1970 [45] Patented Oct. 12, 1971 [54] HYDRAULIC VALVE CONTROL SYSTEM 6 Claims, 5 Drawing Figs.

[52] US. Cl 123/90.l2, 123/9016 [51] Int. Cl F011 9/02 [50] Field of Search 123/9012, 90.15, 90.16, 90.17, 90.18

[56] References Cited UNITED STATES PATENTS 1,696,984 1/1929 Trbojevich 123/9012 1,876,735 9/1932 Noble 123/9012 1,994,223 3/1935 Leveque 123/9012 2,011,864 8/1935 Lundh..... 123/90.12X 2,494,183 1/1950 Lincoln 123/9016 X 2,615,438 10/1952 Tucker 123/9012 2,829,628 4/1958 Smiltneek 123/90.12 3,405,699 10/1968 Laas 4 123/9012 X Primary Examiner-Al Lawrence Smith Att0rneyFreeman & Taylor PATENTEDncnzmn 3612015 SHEET 1 [IF 2 w A ,1 k L:\38 36 32 200 2O INVENTOR. LOU/S A. HAUSKNECHT ATTORNEYS HYDRAULIC VALVE CONTROL SYSTEM BACKGROUND OF THE INVENTION In the art of automotive engines, it is conventional practice to employ a crankshaft that is rotated in response to firing of the various cylinders. The crankshaft, in turn is provided with cam followers that serve, through appropriate connections, to open and close the engine valves for the purpose of admitting fresh charges of fuel above the cylinders.

At the present time, no provision is made for varying the extent of time that the engine valves are in open position during each cycle of the operation. Accordingly, and in particular in the case of high-performance automobiles, the engine will not operate smoothly at lower speeds in view of the fact that both the intake and exhaust valves are open at the same time permitting some of the fresh charge of fuel to escape through the exhaust. In addition to contributing to air pollution this causes efficient performance at low operating speeds to be sacrificed inorder to achieve high-performance efficiency at maximum operating speeds.

SUMMARY OF TI'IE'INVENTION It has been discovered that the above situation can be ob-.

viated by providing means that can be simply operated to vary the amount of time that an engine valve is open during each cycle of operation. Thus, during high-performance operation, and by use of the means hereinafter described, the engine valve can be left open for a relatively great period of time during each cycle of operation so as to assure receiving the maximum amount of fuel.

On the other hand, and by operating the control means to a different low-speed position, i.e. idling or the like, the engine valve will remain open for a relatively lesser degree of time during each cycle of operation so that the timing can be adjusted to any level of performance that is desired by the operator.

The preferred means employed for achieving such an effect include in the preferred form shown, a closed hydraulic system or circuit that has fluid connections with (l) the slave cylinder (2a hydraulic master cylinder that is actuated by the camshaft, and (3) control means per se.

By this arrangement, the volume allocation within the closed hydraulic circuit will vary in response to the movement of the components that are fluidly connected thereto, and as the volume is shifted, for example, this will serve to move the reciprocal components to a different position so as to change the operating characteristics of the system.

More specifically, as the master hydraulic cylinder piston moves upwardly to redistribute the fluid in the circuit, the movement of the fluidic volume will serve initially to shift a portion of the control mechanism to what will be referred to as an extended position," with the force of a restraining spring being overcome during such movement, and with an eccentric cam serving as a stop to determine the amount of and limit the extent of such movement.

However, if the master cylinder piston movement continues, the engine valve per se will next be moved to its open position so as to admit fuel at the top of the piston cylinder.

Finally, and when the extreme maximum movement is being approached, the remaining component of the control unit will be open.

Conversely, if the master cylinder piston descends during the remaining portion of the cycle, the component parts just described will return to their normal or closed positions in a reverse sequence, with the high-speed control unit of the control mechanism closing first, followed by the closing of the engine valve and the low'speed control plunger of the valve mechanism, in that order.

Since the amount of movement of the low-speed control valve is variable and since the extent of opening movement of the engine valve is limited, it is believed apparent that a considerable variable exists with regard to the amount of time that the engine valve will be open during each cycle of operation.

Since this variable can be readily ascertained by the operator, it is believed apparent that extremely fine control exists with regard to the valve timing and performance capabilities of the automobile engine.

Production of a timing control mechanism of the type above described becomes the principal object of this invention, with other objects thereof becoming more apparent from a reading of the following brief specification, considered and interpreted in view of the drawings.

OF THE DRAWINGS FIGS. 1 through 5 are schematic views showing the component parts in the various positions they assume during each typical cycle of operation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, theusual crankshaft 10, is connected in known manner to a piston rod 11 which is, in turn, appropriately pinned to apiston head 12 that reciprocates within thecylinder 13.Intake port 14 has anengine valve 15 associated therewith forcontrol of the entry of fuel into the cylinder portion disposed above thepiston head 12, withspring 16 operating againststop 17 so as to normally urge theengine valve 15 to the closed position shown in FIG. 1.

In this regard,sleeve 18 is also provided around the stem ofvalve 15 to limit the amount of opening movement that can be achieved by theengine valve 15, as will be hereinafter described in greater detail.

Also provided on thecrankshaft 10 is acrankshaft timing gear 20, that meshes with thecamshaft gear 21 and has anappropriate cam 22 provided thereon. Acam follower 23 rides oncam 22 and is secured to the lower end of apush rod 24, with the push rod .24 being connected to a hydraulicmaster cylinder piston 26 that reciprocates within anappropriate bore 27a ofhousing 27.

As shown on the drawings, thehousing 27 ofunit 25 includes afurther bore 27b within which reciprocates aslave piston 28 that is, in turn, attached to the projecting top end of theengine valve 15.

Additionally, and as shown schematically, a third bore orport 27c is provided for the purpose of fluidly connecting thehousing 27 with acontrol unit 30, by a high-pressure fluid line 31, with asecond line 32 also being connected to thecontrol unit 30 and leading fromunit 30 to the oil pump (not shown) of the engine in known fashion.

Thecontrol unit 30, as schematically illustrated in FIGS. I through 5, includes acylindrical housing 35 within whichcontrol units 36 and 37 reciprocate.Unit 36 will hereinafter be referred to as the low-speed control unit since it is normally utilized at lower engine speed, whileunit 37 will be hereinafter referred to as the high-speed control unit since it is normally utilized at the upper level of engine operating speeds.

Both thecontrol units 36 and 37 are urged toward each other bysprings 36a and 37a, with apin 38 serving to space the members apart so as to permit entry of fluid therebetween throughline 31a, as shown in the drawings. While thespring 37a rests against thestop 39, as shown, the arrangement of thespring 360 is somewhat different as will now be described.

In this regard, a pin andconcentric shaft 40 is telescopically received within the low-speed control unit 36 and has aplate 41 on the end thereof for abutment withaneccentric disc 42 that can be operated circularly by means of acontrol handle 43.

By this arrangement, the amount of shifting movement of thecontrol unit 36 withinhousing 35 can be varied with the drawings illustrating the maximum point of movement because of the position of theeccentric disc 42. In this regard, theeccentric disc 42 pivots aroundpivot point 42a so that minimal movement ofcontrol unit 36 would be permitted if the plate were rotated from the condition shown in FIG. 1 for example.

An annularundercut portion 36b is also provided on theunit 36 for registry with thefluid lines 31 and 32 so as to permit communication therebetween during the period that said unit is in the retracted position of FIG. I, for example. It is to be understood that the usual seals and the like would be provided and the same are not illustrated in the schematic rendition in view of the fact they do not, per se, constitute a part of this invention.

It will, thus, be seen that the hydraulicmaster cylinder piston 26, theslave cylinder piston 28, and thecontrol units 36 and 37 are all in fluid communication with the enclosed hydraulic circuit, with the distribution of volume within this circuit being changed by reciprocation of themaster cylinder piston 26 so as to increase or decrease the pressure being applied to the various components, depending upon the direction of such movement. It is also believed apparent that this movement will serve to move the just-describedmembers 28, 36, and 37 to different positions, with the spring strength and pressure response arrangements of each unit being such that theunit 36 will move at one elevated pressure while theunit 28 will move at a higher elevated pressure, and finallyunit 37 will move at the highest of the three actuating pressures encountered during each cycle of operation.

The operation of the timing mechanism is substantially as follows. In FIG. I, the hydraulicmaster cylinder piston 26 is in its down" position due to the position of thecam follower 22. At this time, the pressure within the hydraulic circuit is at a minimum and all pistons and plungers are in their normal or retracted position.

However, as piston I2 is driven downwardly,crankshaft timing gear 21 rotates in the direction ofarrow 20a and, in turn, rotatescamshaft gear 21 in the direction ofarrow 21a.

This causes the fluid within the circuit to be forced out ofcylinder bore 21a due to the upward movement of themaster cylinder piston 26 in the direction ofarrow 26a, as shown in FIG. 2. Since the fluidic volume of the hydraulic circuit will be redistributed, a resultant increase in interior pressure on the other components will occur. This increase in pressure will be transmitted throughport 31a against the pressure response face of theunit 36 so that the force ofspring 36a will be overcome to cause a shifting of theunit 36 to the left, in the direction ofarrow 50 in FIG. 2. The amount of such shifting movement will be halted when thespring 36a is fully collapsed, as shown in FIG. 2, and flow from the oil pump will be stopped.

When further increase in pressure occurs due to further upward movement of thepiston 26, as shown in FIG. 3, theslave cylinder piston 28 will be moved downwardly to the position shown in FIG. 3, with such downward movement overcoming, of course, the force of the spring I6 so as to open theengine valve 15, with the extent of such opening movement being limited by abutment of spring retaining plate 117 with the projecting end of the sleeve I8.

Finally, and as the pressure reaches its maximum, as shown in FIG. 4, the force ofspring 37a will be overcome and thecontrol unit 37 will shift to the right, as shown in FIG. 4, and indicated by thearrow 60.

It should be understood that theeccentric disc 42 is so positioned in the drawings as to permit maximum movement ofcontrol unit 36. Movement ofcontrol handle 43 will, of course vary this.

Thus, for high-operating speeds it is desirable to openvalve 15 further and hold theengine valve 15 open for a longer period. Therefore, the less to theleft control unit 36 can travel, the farthervalve 15 will open and the longer valve I will be held open.

It has been previously indicated that due to the spring strength and hydraulic piston cross-sectional area, that the control elements will operate in a given sequence and it, accordingly, follows in view of this that during depressurization, the sequence of operation will reverse itself, with thecontrol unit 37 first closing (as shown in FIG. 5), followed by closing respectively of the engine valve and finallycontrol unit 36,

It should be noted that the size ofcontrol units 36 and 37 have been considerably exaggerated for purposes of illustration and these units would normally be much smaller thanmaster cylinder piston 26, for example.

Also, while thecontrol mechanism 30 is shown as including two units, it is to be understood that both of such units are not required to achieve improved performance of an automotive engine.

Thus, for example, if thecontrol unit 37 were eliminated, there would still be a variable timing system.

While a full and complete description of the invention has been set forth in accordance with the dictates of the Patent Statutes, it is to be understood the invention is not intended to be limited to the specific form shown.

Thus, and for example, and while manual operation throughrod 43 is shown, it is believed apparent that such valve operation could be automated by appropriate connection with the automobile accelerator, for example, so that the valve would be operating in response to the accelerator. It is also believed apparent that while the device has been shown and illustrated in connection with an automobile engine, the same would be equally applicable to any internal combustion engine.

Accordingly, modification of the invention may be resorted to without departing from the spirit hereof or the scope of the appended claims.

What is claimed is:

I. In combination with an internal combustion engine having an engine valve and rotating crankshaft, the improvement comprising;

A. a closed hydraulic circuit having fluid communication with l. a reciprocal hydraulicslave cylinder piston 2. a reciprocal hydraulic master cylinder piston 3. a valve control mechanism having at least one reciprocal unit, said unit being reciprocal between normal and extended positions in response to internal volumetric distribution variations within said hydraulic circuit;

B. said hydraulic slave cylinder piston being operatively associated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions;

C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston;

D. the internal pressure required to move said slave cylinder piston being higher than the internal pressure required to move said valve control mechanism; and

E. means for varying the amount of movement of said reciprocal unit of said valve control mechanism and the duration of time that said engine valve is in said open position during each revolution of said crankshaft.

2. The improvement of claim I further characterized by the presence of means for limiting the extent of opening movement of said engine valve.

3. The improvement of claim 1 further characterized by the fact that said means for varying the amount of movement of said reciprocal unit include a cam surface positioned in contact with said reciprocal unit of said valve control mechanism.

4. In combination with an internal combustion engine having an engine valve and rotating crankshaft, the improvement comprising;

A. a closed hydraulic circuit having fluid communication with l. a reciprocal hydraulicslave cylinder piston 2. a reciprocal hydraulic master cylinder piston 3. a valve control mechanism having at least one reciprocal unit, said unit being reciprocal between normal and extended position in response to internal volumetric distribution variations within said hydraulic circuit;

B. said hydraulic slave cylinder piston being operatively associated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions;

C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston; and

D. the internal pressure required to move said slave cylinder piston being less than the internal pressure required to move said hydraulic valve control mechanism, whereby the period of time that said engine valve is in said open positions will be extended by the period of time said reciprocal unit of said valve control mechanism is in said extended position during each revolution of said crankshaft.

5. In combination with an internal combustion engine having an engine valve and rotating crankshaft, the improvement comprising;

A. a closed hydraulic circuit having fluid communication with l. a reciprocal hydraulicslave cylinder piston 2. a reciprocal hydraulic master cylinder piston 3. a valve control mechanism including first and second reciprocal units that each are reciprocal between normal and extended positions in response to internal volumetric distribution variations within said hydraulic circuit;

B. said hydraulic slave cylinder piston being operatively as-- sociated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions;

C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston; and

D. the internal pressure required to move such slave cylinder piston being higher than the internal pressure required to move said first reciprocal unit of said hydraulic valve control mechanism; and

E. means for varying the amount of movement of said first reciprocal unit of said valve control mechanism whereby the duration of time that said engine valve is in said open position during each revolution of said crankshaft may be varied.

6. The device of claim 5 further characterized by the fact that the internal pressure required to move said second reciprocal unit of said valve control mechanism to its extended position is greater than the internal pressure required to move said slave cylinder piston to its extended position whereby the period of time that said engine valve is in said open position will be extended by the period of time said second reciprocal unit of said valve control mechanism is in said extended position during each revolution of said crankshaft.

Claims (12)

1. In combination with an internal combustion engine having an engine valve and rotating crankshaft, the improvement comprising; A. a closed hydraulic circuit having fluid communication with 1. a reciprocal hydraulic slave cylinder piston 2. a reciprocal hydraulic master cylinder piston 3. a valve control mechanism having at least one reciprocal unit, said unit being reciprocal between normal and extended positions in response to internal volumetric distribution variations within said hydraulic circuit; B. said hydraulic slave cylinder piston being operatively associated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions; C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston; D. the internal pressure required to move said slave cylinder piston being higher than the internal pressure required to move said valve control mechanism; and E. means for varying the amount of movement of said reciprocal unit of said valve control mechanism and the duration of time that said engine valve is in said open position during each revoluTion of said crankshaft.

2. a reciprocal hydraulic master cylinder piston

2. The improvement of claim 1 further characterized by the presence of means for limiting the extent of opening movement of said engine valve.

2. a reciprocal hydraulic master cylinder piston

2. a reciprocal hydraulic master cylinder piston

3. a valve control mechanism having at least one reciprocal unit, said unit being reciprocal between normal and extended positions in response to internal volumetric distribution variations within said hydraulic circuit; B. said hydraulic slave cylinder piston being operatively associated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions; C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston; D. the internal pressure required to move said slave cylinder piston being higher than the internal pressure required to move said valve control mechanism; and E. means for varying the amount of movement of said reciprocal unit of said valve control mechanism and the duration of time that said engine valve is in said open position during each revoluTion of said crankshaft.

3. a valve control mechanism having at least one reciprocal unit, said unit being reciprocal between normal and extended position in response to internal volumetric distribution variations within said hydraulic circuit; B. said hydraulic slave cylinder piston being operatively associated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions; C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston; and D. the internal pressure required to move said slave cylinder piston being less than the internal pressure required to move said hydraulic valve control mechanism, whereby the period of time that said engine valve is in said open positions will be extended by the period of time said reciprocal unit of said valve control mechanism is in said extended position during each revolution of said crankshaft.

3. a valve control mechanism including first and second reciprocal units that each are reciprocal between normal and extended positions in response to internal volumetric distribution variations within said hydraulic circuit; B. said hydraulic slave cylinder piston being operatively associated with said engine valve whereby reciprocal movement of said slave cylinder piston will result in reciprocal movement of said engine valve between open and closed positions; C. said hydraulic master cylinder piston being operatively associated with such crankshaft whereby rotation of said crankshaft results in reciprocal movement of said master cylinder piston; and D. the internal pressure required to move such slave cylinder piston being higher than the internal pressure required to move said first reciprocal unit of said hydraulic valve control mechanism; and E. means for varying the amount of movement of said first reciprocal unit of said valve control mechanism whereby the duration of time that said engine valve is in said open position during each revolution of said crankshaft may be varied.

3. The improvement of claim 1 further characterized by the fact that said means for varying the amount of movement of said reciprocal unit include a cam surface positioned in contact with said reciprocal unit of said valve control mechanism.

4. In combination with an internal combustion engine having an engine valve and rotating crankshaft, the improvement comprising; A. a closed hydraulic circuit having fluid communication with

5. In combination with an internal combustion engine having an engine valve and rotating crankshaft, the improvement comprising; A. a closed hydraulic circuit having fluid communication with

6. The device of claim 5 further characterized by the fact that the internal pressure required to move said second reciprocal unit of said valve control mechanism to its extended position is greater than the internal pressure required to move said slave cylinder piston to its extended position whereby the period of time that said engine valve is in said open position will be extended by the period of time said second reciprocal unit of said valve control mechanism is in said extended position during each revolution of said crankshaft.

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