US3548793A - Valve actuating mechanism for internal combustion engines - Google Patents

Description

O United States Patent [111 3,54

72] Inventor James S. Richardson 2,164,114 6/1939 Kolb 123/102X 6405 Edgemoor, Houston, Tex. 77036 2,692,588 10/1954 Cathers 123/90 [21] Appl. No. 772,150 2,827,884 3/1958 Stivender 123/90 [22] Filed Oct. 31,1968 3,028,939 4/1962 Glick 123/102X [45] Patented Dec. 22, 1970 3,209,737 10/1965 Omotehara et a1. 123/90 3,397,681 8/1968 Northrup 123/90 [54] VALVE ACT-DATING MECHANISM FOR Primary Examiner-A. Lawrence Smith INTERNAL COMBUSTION ENGINES Attorney-Charles E. LightfOOt 4Cll1ms,6Draw1ngFlgs. V w V US. Cl. valve actuating and timing mechanism for inter. 1, 123/90-15, 123/90-61 nal combustion engines embodying hydraulic means for open- [51] Int. Pl Foil ing the engine valves under the control of electrically operated 0 1 F011 hydraulic valve mechanism responsive to photoelectric timing [50] Field 0' Search 123/90, 102 mechanism whose timing is varied in accordance with engine speed. The mechanism includes a hydraulically operated Refemnm Cited valve-opening system having solenoid actuated hydraulic UNITED STATES PATENTS valves which are responsive to timing mechanism embodying a 885,459 4/1908 Engler et a1 123/90 photoelectric cell for each engine valve to be opened, a light 1,377,297 5/1921 Werner 123/90 source, and rotary shutter means which is variable with engine 1,471,861 10/1923 Perrault 123/90 speed to automatically vary the exposure of the photoelectric 1,472,613 10/1923 Nicholson 123/90UX cells to light from said source to control the timing and dura- 1,760,853 5/1930 Wood 123/90 tion of opening of the engine valves.

PATENTED UEC22 I970 SHEET 1 OF 2 w 3 3 E Nm Nm 3 James S. Richardson /N VE N TOR BY g 5 ATTORNEY PATENTED [150221970 3,548,793

' SHEET 2 OF 2 a4 v k yg f 1/2 88/ k no JO James S. Richardson IN VE N TOR WKW ATTORNEY VALVE ACTUATING MECHANISM FOR INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION The invention relates to the operation of valves of internal combustion engines of the type having timing mechanism which is driven by the engine. The valves of engines of this kind are customarily opened by cam shafts rotated in response to engine speed, the cams of such shafts being positioned and shaped to accomplish the opening of the valves and the dwell or duration of such opening.

As ordinarily constructed, the cams of such cam operated valve mechanism are of a predetermined fixed shape, so that the opening of the valves always takes place when the cam shaft reaches a predetermined position of rotation which is not variable and the duration of opening of the valves is determined by the dwell portion of the cams and varies only in response to the speed of rotation of the cam shaft.

Various attemptshave been made to provide for the advancing or retarding of the opening position of the cams and varying the dwell portion of the same, such as by moving the cam shaft longitudinally of its axis in response to changes in engine speed and contouring or shaping the cam to change the position of rotation at which lifting of the valves begins and the length of the dwell portion of the cam. Such means for varying valve actuation has not proven satisfactory, however, due to the complexity of the mechanism required, which is subject to great stresses in operation s as well as extreme conditions of wear.

SUMMARY OF THE INVENTION Briefly described the invention comprises hydraulic valve actuating mechanism having a hydraulic pressure cylinder for each valve to be operated and including a solenoid actuated valve for controlling the admission of hydraulic fluid into and the discharge of such fluid from each cylinder, photoelectric means for controlling the energization and deenergization of the solenoids including a light source, a photoelectric cell for each solenoid and rotary shutter mechanism for controlling the exposure of the cells to the light source and cutting ofi such exposure in response to variations in engine speed. The rotary shutter mechanism also includes means for advancing and retarding the exposure of the photoelectric cells to the light source and for. varying the duration of such exposure in response to changes in engine speed.

The hydraulic valve-actuating mechanism provides for the application of hydraulic fluid under pressure to the valve actuating cylinders to accomplish quick opening of the engine valves and for the free outflow of such fluid from the cylinders to reduce the resistance to closing movement of the valves to accomplish rapid closing of the same.

The invention includes solenoid means for operating a valve of an internal combustion engine in combination with electric photocell and shutter mechanism responsive to engine speed for controlling the valve operation.

BRIEF DESCRIPTION OF THE VIEWS or THE DRAWINGS FIG. 1 is a fragmentary view partly in cross section and partly diagrammatic illustrating a preferred embodiment of the valve actuating mechanism of the invention;

FIG. 2 is a vertical, central, cross-sectional view on an enlarged scale, showing details of structure of the hydraulic valve-actuating means of the mechanism, showing the same in its valve opening position; I

FIG. 3 is a view, similar to that of FIG. 2 showing the valveactuating means in the valve-closed condition;

FIG. 4 is a cross-sectional view taken along the line 4-4 of FIG. 1, looking in the direction indicated by the arrows;

FIG. 5 is a fragmentary side elevational view of the rotary shutter of the valve-timing means of the mechanism, showing details of structure of the same; and

FIG. 6 is a fragmentary cross-sectionalview similar to FIG. 1, illustrating a somewhat modified form of the engine valveactuating mechanism of the invention.

DETAILED DESCRIPTION OF A PARTICULAR EMBODIMENT OF THE INVENTION Referring now to the drawings in greater detail the invention is disclosed herein in connection with its application to an internal combustion engine of a usual type having a cylinder head 10 formed with the usual valve ports, such as the port 12, which is opened and closed by a valve 14, whose valve stem 16 is provided with a coil spring 18 positioned for coaction with the valve and head to yieldingly urge the valve toward closed position. The valve is opened in the usual manner by a rocker 20, rotatably mounted on a post 22 on the cylinder head and having one arm 24 thereof positioned to bear at its free end on the upper end of the valve stem, as by means of a suitable bearing 26, and its other arm 28 bearing at its free end on the upper end of a plunger 30, of a hydraulic pressure cylinder 32, as by means of a ball bearing 34. The hydraulic pressure cylinder is supported on a base 36 resting on the cylinder head, which base has a bore 38 therein in which a valve 40 is slidably disposed. The bore 40 is closed at one end, and the base is formed at the'other end of the bore with an externally reduced portion 42, surrounded by an elongated, cylindrical cap or cover 44 formed with a counterbore 46, within which a coil spring 48 extends which bears against one end of the valve 40 to yieldingly urge the valve in one direction in the bore.

The bore 38 is in communication with the interior of the pressure cylinder 32 through an inlet passageway 50 and an outlet passageway 52 and an inlet supply pipe 54 is connected in communication with the bore through a port 56 opposite the inlet passageway 50, while an outlet pipe 58 is connected in communication with the bore through an outlet port 60 located opposite the outlet passageway 52.

The valve 40 has a reduced portion 62 positioned to establish communication between the inlet pipe 54 and inlet passageway 50 to supply hydraulic fluid under pressure to the pressure cylinder 32 beneath the plunger 30 to lift the plunger when the valve is in the position of FIG. 2, and a reduced portion 64 positioned to establish communication between the outlet pipe 58 and outlet passageway 52 to allow an outflow of liquid from the cylinder 32 to permit the plunger 30 to move downwardly when the valve is in the position illustrated in FIG. 3. The valve also has a portion 66 located between the reduced portions 62 and 64 which is positioned to close the outlet passageway 52 when the inlet passageway 50 is open and to close the inlet passageway when the outlet passageway is open.

The valve 40 also has an elongated portion 68 which is slidably extended into the externally reduced portion 42 of the base, upon which reduced portion an electric wire is wound to form a solenoid coil 70 surrounding the bore and which may be energized from any suitable source of electrical current to cause the valve to move from the position of FIG. 3 to the position of FIG. 2 and to allow the valve to be returned to the position of FIG. 3 by the spring 48 when the coil is deenergized.

I It will be apparent that upon energization of the solenoid 70, valve 40 will be moved from the position of FIG. 3 to the position of FIG. 2, to open the inlet passageway 50 and close the outlet passageway 52, whereupon liquid under pressure is supplied to the cylinder 32 to lift the plunger 30, thus actuating the rocker 20 to move the valve 14 to open position and upon deenergization of coil 70 the valve 40 will be moved by spring 46 to the position of FIG. 3 to close inlet passageway 50 and open outlet passageway 52 to allow an outflow of liquid from cylinder 32, whereupon valve 14 will be closed by spring 18 and the rocker 20 will be actuated to move plunger 30 downwardly.

For the purpose of timing the valve-actuating mechanism to open the valves of the engine, the invention includes electrical-timing mechanism comprising a stationary cylindrical casing or housing 72, mounted at some convenient location and having a closure 74 at its upper end provided with a central opening from which a tube 76 extends downwardly in the casing, and also having a lower end wall 78 formed with a central opening from which a tubular extension 80 extends downwardly exteriorly of the casing.

The casing 72 is provided with peripherally spaced openings 82 in its sidewall, one for each of the valves of the engine which are to be operated, and within each of which a photocell 84 is positioned to be exposed to light from an electric lamp 86 located centrally in the casing at the lower end of the tube 76.

Within the casing a rotary shutter device 88 in the form of a cylinder is mounted on a shaft 90 for rotation therewith which shaft is rotatably extended through the tubular extension 80, as by means of suitable bearings 92 located therein, the shaft being adapted to be rotated in accordance with engine speed, by any suitable means, not shown, such as by timing gear mechanism of a well-known type, or by a belt drive powered by the engine or otherwise. The shaft 90 is extended into a central bore 94 of a downwardly extending lower end portion 96 of the rotary shutter upon whose free end a tapered annular flange 98 is formed having a downwardly facing beveled face 100.

The shaft 90 carries a pair of bellcrank levers 102, pivotally mounted thereon at diametrically opposite locations, each of which has at the free end of one arm 104 thereof a weight 106, and at the free end of the other arm 108 thereof a roller 110 positioned for engagement with the beveled face 100. It will be apparent that, as the speed of rotation of the shaft increases the weights 106 will tend to move outwardly and the arms 108 will be elevated correspondingly to lift the rotary shutter, and when the speed of the shaft is reduced the weights will move inwardly to swing the arms 108 downwardly to allow the shutter to move downwardly.

The rotary shutter 88 has a vertically elongated slot 112 through its sidewall which may slope upwardly somewhat in the direction of rotation of the shutter and which may also increase somewhat in width from top to bottom. The slot 112 is positioned to allow light from the lamp to pass therethrough to expose each of the photocells 84 successively to light for a predetermined time, which will vary in accordance with changes in speed of the engine.

Each photocell 84 is connected into an electrical circuit, shown in FIG. 1 provided with current from any suitable source, such as a battery 114 and into which one of the solenoid coils 70 is also connected. Thus, each of the photocells 84 is connected into circuit with one of the solenoid coils 70 to cause energization of the solenoid when the photocell is exposed to light from the lamp 86.

The lamp 86 is also connected into a circuit with the battery 114 under the control of a switch 116, which may be the ignition switch of the engine. The switch 116 may also be connected in circuit with the photocells 84 and battery 114, so that the cells will receive current only when the ignition system of the engine is on.

Hydraulic fluid for the actuation of the plungers 30 is supplied to the cylinders 32 through the inlet pipes 54, best shown in FIG. 1, which are connected to a manifold 120 to which such fluid is supplied to the cylinders 32 at high pressure to actuate the plungers 30, while resistance to the outflow of return fluid from the cylinders is reduced to a minimum, thus allowing the valves 14 to close rapidly.

By constructing the cylinders 32 with their lower end portions of substantially larger diameter than the upper end portions thereof, and forming the plungers 30 with correspondingly shaped upper and lower end portions, a large area is provided against which the hydraulic fluid may act to lift the plungers, thus greatly increasing the opening force applied to the valves 14.

In the operation of the mechanism, as the speed of the engine increases the rotary shutter will be elevated to position the slot 112 so that the timing of the exposure of the photocells to light from the lamp 86 will be advanced, but reduced in duration, thereby opening the valves 14 earlier but maintaining same open for a shorter time. The slot 112 may, of course, be shaped to obtain any desired timing and duration of exposure of the photocells, whereby timing of the valves 14 may be adjusted and regulated to any desired degree.

A somewhat different form of the invention is illustrated in FIG. 6, wherein the valve rocker 20'is'actuated by an electrically operated plunger 30' which operates in a solenoid housing 36 within which a solenoid coil 32' is enclosed. The outer end of the plunger 30' carries a suitable bearing 34 against which the arm 28 of rocker 20 rests. The solenoid coil 32 is connected into the electric circuit with the photocells 84 in the same manner as the solenoid coil 70 of the form of the invention illustrated in FIGS. 1, 2 and 3 to actuate the engine valve directly in response to engine speed.

The operation of this modified form of the invention is believed to be obvious, the engine valve being actuated by the solenoid in response to variations in engine speed.

The solenoid apparatus 30', 32' may, of course, be of a double-acting type, not shown, suitably connected into the timing circuit in a manner for actuation to both open and close the engine valve, should such an operation be desires.

It will thus be seen that the invention provides valve-actuating and timing mechanism which is of simple design and rugged construction and by which the opening and closing of the valves may be accomplished at high velocity while accurately timing the operation of the valves in accordance with engine speed.

The invention is disclosed herein in connection with a particular embodiment of the same, which is it intended by way of illustration only, it being evident that various changes can be made within the spirit of the invention and the scope of the appended claims.

I claim:

1. Mechanism for opening and closing a valve of an internal combustion engine comprising:

a pressure cylinder;

a plunger movably disposed in the cylinder, said cylinder having an inlet and an outlet located on one side of the plunger;

actuator means for opening the valve including means positioned for coaction with the plunger and valve to open the valve in response to movement of the plunger in one direction in the cylinder;

means for supplying fluid under pressure to said inlet;

means responsive to the running of the engine for simultaneously opening the inlet and closing the outlet to admit fluid under pressure to the cylinder to move the plunger in said one direction and for simultaneously closing the inlet and opening the outlet to allow the outflow of such fluid from the cylinder to allow movement of the plunger in the other direction in response to closing movement of the valve;

means responsive to a change in the speed of the engine for changing the time of the opening and closing of said inlet and outlet including;

a light source;

a photoelectric cell;

rotatable shutter means positioned to allow the exposure of said cell to light from said source during one portion of rotation of the shutter means and to shut off such exposure during another portion of such rotation; and

means forming a driving connection between the engine and said shutter means to rotate the shutter means in response to running of the engine.

2. The mechanism as claimed in claim 1, wherein said shutter means includes a cylindrical casing enclosing said light source and having an opening in the sidewall thereof through which light from said source may pass to said cell during one portion of the rotational movement of the shutter means.

the shutter means in the other direction.

4. The mechanism as claimed in claim 3 wherein said opening is shaped to advance the time at which light from said source may begin to pass through the opening to said cell upon an increase in the speed of the engine and to retard the time at which such passage of light may begin upon a decrease in the speed of the engine.

Images