US902725A - Valve-operating mechanism. - Google Patents

Description

A E. GREENE. VALVE OPERATING MECHANISM. APPLICATION FILED 111N315, 1907.

Patented Nov. 3, 1908.

. E m 4 w E Z j M j 1 w 2 A 5 Z w wfiw F5. 5 W/ 77v555 (7 40 fiwf/s ATTORNEY AMBROSE EVERTS GREENE, F MARSHFIELD, OREGON.

VALVE-OPERATING mcnAmsM.

Specification ofLetters Patent.

Patented Nov. 3, 1908.

Application filed June 16, 1907. Serial No. 379,215.

To all whom it may concern:

Be it known that I, AMBROSE EVERTS GREEN of Marshfield, in the county of Coos and State of Oregon, have invented certain newand useful Improvements in Valve- Operating Mechanism, of which the following is a specification.

This invention relates to mechanism.

More particularly, it relates to means for operating the valves and ignition of a fourcycle internal combustion engine, and for reversin such engine.

The 0 jects-of the invention are to eliminate gear wheels from the valve operating mechanism and substitute therefor a simple reciprocating motion; to effect the ignition under conditions calculated to secure the greatest efiiciency, b the same mechanism;

valve operating and to provide for t e ready reversal of the engine.

These objects are accomplished by the mechanism illustrated in the accompanying drawing, which represents one embodiment of the invention.

In the drawingsFigure 1 represents an elevation of the operating, mechanism, viewed as if sectioned on line 1,1 of Fig. 3. Fig. 2 is a plan of the same, sectioned on the line 22 of Fig. 1. Fig. 3 is a somewhat diagrammatical view showing, in elevation, the relation of these parts to the engine.

' Figs. 4 and 5 are sectional elevations of a detail seen respectively from the side, as in Fig. 1, and from the front, as in Fig. 3. Figs. 6 and 7 are sectional views showing another detail in side and. front views respectively.

In the drawings the invention is represented as it may be applied to an upright en gine, the mechanism and general arrangement of which may be of any suitable form.

As here shown, the reference numeral 10 indicates the frame of the engine, within which the cylinder and principal moving parts are contained.

11 is the main drivin shaft of the engine, and12' the driving whee l.

13 is the exhaust pipe, 'flffld'ljl; the lever of a valve 15 therein which is to be controlled through the agency of the mechanism about to be'describe Onshaft 11 is a collar 16, holding fasta cam 17 thereon which operates aroller 18. Another collar 19 has a rojecting lu or arm .w'which rotates with tli e cam. Roller 18 is mounted on a lever 21, having-a block 22,

'tion chamber of the engine.

with a cup-shaped or conical depression 23 in its top, in which is seated the hub 24 of a wheel having four spokes 25. This wheel rotates in the said bearing 23, and may be a tube 28 is a spring 30, and the upper end of the tube is closed so that when the pin 26 rises it compresses spring 30 and is sub ject to the downward pressure of that spring. A rod 31 forms a continuation of the tube upward, being suitably guided in a hearing at 32, and at its upper end 33 engages valve lever 14. The cross arm 27 has contact points 35, and a suitably insulated spring 36 is stationarily mounted nearby in position for platinum point 37 thereon to make electrical contact with one of the points 35 Whenever the pin 26 rises in cleft 29; and the contact is broken when the pin falls. The spring 36 forms part of an electrical circuit, being con nected through a conductor 38, which circuit is completed through contacts 37 35, cross arm 27, pin 26, and through tube 28 or spring 30, or both, to rod 31, and thence through another conductor to the induction coilipr causing the spark in the engine, and back to the battery.

In operation, the shaft 11 makes one 00111- plete revolution for each two cycles in the engine cylinder, thus engaging one of the spokes 25 and rotating 'pin 26 one-quarter revolution. As shown in Fig. 1, the cam 17 is in position to raise roller 18, thus raising pin 26; and that pin is in position to enter cleft 29 whenso raised, thus making electrical contact between 35 and 37. This corresponds to the beginning of the fourth cycle, the completion of which occurs when the portion 40 of the'cam 17 reaches roller 18, allowing that roller to drop, and with it the pin 26, breaking the circuit between 37 and 35. This causes the ignition spark in the combus- The next half revolution of the cam carries it again to the position shown in Fig. l, and while doing so the arm 20 engages the next spoke 25 and turns it and pin 26 one-quarter revolution. This reaches the end of the first cycle, an at the beginning of the second, eam roll raises cross arm 27, which, not being under cleft 29, engages the fiat end 41 of the tub 28,"lifting the entire tube and rod 31 and tln lution of the cam 17, which is the second.

the roller.

cycle; and closes when cam face 40 reaches lhu'ing the third cycle pin 26 remains down and arm turns the pin another quarter revolution, so that when roller 18 rises atthe beginning of the fourth. cycle the cross arm 27 enters the cleft 29 and does not raise tube 28, and therefore does not operate the exhaust valve, but does make the electrical connection as above described.

The rod 31 may preferably be squared in order to prevent its rotation. The edges of the cleft 29 may be'beveled or rounded, as indicated, to receive rod 27 unfailingly, even though it be not accurately positioned. When the engine is not designed to be reversible the cam 17 is firmly keyed to shaft 1. 1, but the mechanism may be adapted for operation of the engine in reverse direction by mounting the cam 17 loosely on shaft 11 and providing a key 42 set in the shaft, and a groove. 43 in the cam next the shaft, in which the key may slide from the position shown in Fig. 6 untilthe cam has turned 180 degrees about the shaft. Thus, the groove is made .1&@ degrees long plus the thickness of the key. A set-screwor other suitable means is provided to lock thecam in oi ther position. Upon the reversing of the cam the position of the arm 20 should be reversed likewise 180 degrees. It is, therefore, convenient in an engine which is designed to be reversible, to form the collars 16 and 19 in one piece, thus making the arm 20 fast with the cam 17 and in fixed relation thereto. This arrangement is indicated in Fig. 7. It will be noted that the rising of cross-arm 27 in groove 29 serves to draw the pin into percomplished by imparting to it a step by step rotation, by means of tli'c'spohes and lug 20, which alternates with the up-and-don'n J'eciprocaiing movement, which is the actuating stroke, turning the pin successiyely from a position in which it actu ates the valve to a position in which it actuates theignition, and then to a position in which it actuates the valve again, and so on. The cam gives a sharp and desirably quick opening of the exhaust valve. and the fall of the cam gives likewise a quick drop of the pin 26 which enables the break between points By the precision of action in timing the spark the eiiiciency of an ordinary engine may be materiallyincreased, because it can be fixed with certainty, to save loss of explosive power resulting from too late ignition, or loss of energy or back firing resulting from too early ignition; and the accuracy with which it can be timed increases the capacity of an engine, because it enables the valve and ignition mechanism to start promptly into operation at the proper time of stroke.

Another feature of the invention which may be added to the above described parts, if desired, to insure certainty of precise action, is the spring 46, which may be sup ported in any convenient manner, and in thedrawings is represented as supported upon the engine body. braces the pin 26 on opposite sides. A portion of the pin is squared, as represented at 47. When the pin rotates it causes the two forks of the spring to spread until the diagonal of the squared portion has passed one of them, pressing inward, bringing rotation of the pin to rest at precisely a quarter turn. This spring may be formed in any suitable manner. As represented in Figs. 2 and 3, the forks are portions of a fiat spring which have been partly twisted so that they bear flat against the squared pin.

lclaim:

1 Valve operating mechanism, including, i combination, a driving shaft having a This spring is forked and emm and a lug rotating therewith; a pin reeiprocated by the cam and having a series of s okes cngagml by the lug a valve operating rod and an ignition operating device separ t ly actuated by the cam occurring alternatc y with the engagement of said lug with one of said spokes.

2. Valve operating mechanism, including,

in combination, driving shaft having a cam and a lug rotating therewith; a block reciprocatcd by the earn and having a valve and ignition operating pin n'ojecting therefrom, moving therewith an adapted to be engaged and rotated by jthe lug, the cam and the lug acting alternately thereon andimeans whereby the pin actuates the valvejfand the ignition at diilerent'stages of its rotation.

Valve operating imechanism, including, in combination, a driving shaft and aniactuin; the riseof the see,

ating in alternately reciprocated and rotated tractionally thereby; a valve operating rod having a grooved portion, and an igni-- tion operating device, the latter bein in position for engagement with the pin W ien the pinregisters with the opening of the greove, and the former being actuated when it does not so register.

4. Valve operating mechanism, ir iuding, in combination, a valve operating re? and a pin arranged to actuate it, one of these parts having a groove and the other a tongue; an ignition operating device 1 gistoringwith the groove; and means to reei roeate and rotate the pin alternately, where y upon successive reciprocations it alternately registers with the groove, engaging the ignition device, and registers with the rod, actuating the rod,

5. Valve operating mechanism, including, in combination, a valve operating rod having a grooved end; an ignition device having a terminal adjacent to the groove; an actuate ing pin adapted to rise in the groove and make electrical contact, said pin being rotatable and adapted to lift the rod and iniss the 25 contact when not registering with the roove, a series of spokes projecting from t 1e pin; and a driving shaft having a lug thereon adapted to engage the spokes successively, and a cam adapted for raising and lowering the pin alternately with the action of said lug.

6. Valve operating mechanism, including, in combination, a valve operating rod and means to rotate the rod in successive quarter turns, said rod heing squared and there being a flat sprin having two prongs embracing the square rod, saidprongs being each twisted a quarter turn from the plane of the shank of the spring, and bearing fiatwise upon opposite sides of said s uared rod.

In testimony whereof I ereto aflix my signature, in presence of two Witnesses.

AMBROSE EVER'IS QREENE.

Witnesses:

G. W. KAUFMAN, I. F. SMITH.

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