US1196496A - Valve-actuating means for engines. - Google Patents

Description

w. E. VER PLANCK.

VALVE ACTUATING MEANS FOR ENGINES.

APPLICATION FILED JAN- 3, I913.

1,15% Patented Aug. 29, 1916.

Inventor-z William EMer'PlancK His oqttorn e3.

lid

WILLIAM EVERETT VEJR. PLANCK, 0F ERIE, PENNSYLVANIA, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

VALVE-ACTUATING MEANS FOR ENGINES.

Specification of Letters Patent.

Patented An". 29, 191L 13.

Application filed January 3, 1913; Serial No. 739,967.

an internal combustion engine. In one type of such engine with which I am fannhar each cylinder is provided with two oppositely moving trunk pistons, the lower one being connected to the main shaft by a single connecting rod, and the upper one to the shaft by a pair of relatively long rods situated at the sides of the cylinder and pivoted at the top to a cross-head attached v thereto. Pure air is compressed between the pistons on their inward stroke to a tempera ture above the igniting temperature of the fuel, in this case crude oil. Fuel is admitted to the working cylinder by an injector or pulverizer at or about the inner dead center position of the cranks. In the common constructions of such engines the opening and closing of the fuel valve in the pulverizer is controlled by a horizontal cam shaft which is driven by the main shaft through suitable gearing.

I have discovered that an engine of this character can be greatly simplified and the cost of manufacture materially reduced by dispensing with said cam shaft and its driving mechanism, and substituting therefor a means actuated by one of the connecting rods for actuating the valve. As the main crark approaches the inner dead center re gion of the pistons the connecting rods have very little lengthwise movement but a very considerable angular movenient. I utilize this latter fact and so position the valve cam that it is given a suitable movement at approximately the time the rod crosses the inner dead center region of the piston, thereby insuring the opening of the fuel valve at just the portion of the stroke to give the best results, permitting said valve to close promptly after the fuel charge is injected. The cam for actuating the fuel valve may be carried'by the parts moved directly by a side rod or the cam may be mounted on the valve actuator or lifter and be engaged and -moved by a roller carried by the parts moved by said side rod. -One very important feature of m improved construction resides in the fact that the cam or roller, as the case may be, at the time of actuation of the fuel valve is moved in a substantially straight line Which is tangential or nearly so to the orbital path of the actuating pivot onthe side rod.

In the accompanying drawing which is illustrative of my invention, Figure l is a longitudinal section of an engine fitted with my nnproved valve operating means; Fig.-

2' is an enlarged detail view of the same, and Fig. 3 is'"a'slightly modified arrangement wherein they'alve cam is mounted on its lifter. i

5 indicates an engine cylinder of any suitable corlstruction and located therein are pistons 6 and 7, which move in opposite directions. The upper end of the cylinder is provided with a slotted guide 8 for the cross head 9, which is connected by member 10 with the piston pin of the upper piston.

The cross head 9 is connected by a pair of side rods 11, of which one is shown, to the crank 12 of the main shaft 13. The lower piston is connected by a single connecting rod 14 to the crank 15 on the main shaft, the cranks 12 and 15 may be displaced by 180 or by any other definite amount as desired. Fuel is admitted to the engine by the pulverizer or injector 16 and the products of. combustion pass out of the exhaust ports 17. Fresh air is admitted to the cylinder by the ports 18, the ports 17 and 18 being controlled by the upper and lower pistons respectively.

Referring to Fig. 2, 19 indicates the needle valve of the pulverizer, which con trols the admission of fuel to the cylinder. Fuel is admitted to the pulvcrizer through the opening 20, and compressed air for in jecting the fuel against the compression pressure is admitted through the opening 21. The details of construction of the pulverizer are immaterial in so far as this present invention is concerned. The needle valve is normally held on its seatby the coiled compression spring 22 and is. opened by a lifter or actuator made in the form of a bell crank lever. The upwardly extend ing arm of the lever is forked to embrace the valve 19 and resting on the lever is a disk, 23, having a spherical surfaced seat to receive the washer 24, the latter engaging a shoulder on the valve stem. The lower arm 25 of the bell crank lever is provided with an anti-friction roller 26, that is engaged by the cam 27. This cam has imparted to it an orbital motion indicated by the broken and dotted line 28. The cam is so shaped as to gradually open the valve when moved in the direction indicated by the full line arrow and to close rather suddenly after the desired amount of fuel has been admitted to the cylinder. This cam is carried by a projection 29 formed on or secured to the member 30. The cam can be adjusted on the projection by turning the screw 31. The period of opening and closing of the needle valve can thus be madeto occur earlier or later. The engine shown is of the two-cycle type and the cam 27 makes one orbital IHOVBIXlEnhfOI each revolution of the main shaft.

The means for imparting the orbital movement to the cam will now be described.

30 indicates an arm or member that is connected by'the pivot 32 with the side rod 11. This pivot also has an orbital move ment as indicated by the broken and dotted line 33, Fig. 1. The orbit of this pivot is substantially elliptical. From Fig. 1 it will be seen that during the period the cam 27 is engaging the roller 26 the direction of movement of the member 30 and the cam is substantially tangential to the lower part of the orbit described by the pivot 32 in passing through the inner dead center region of the pistons and cranks. As a re sult of this the movement of the cam is very nearly in a straight line. This feature is more clearly shown by the broken. dotted line 28 of Fig. 2. To the member is at- "tached the member 34 by the swinging pivot 35. The upper end of the member 34 is provided with a fixed pivot carried by some portion of the engine frame. The pivots and 36 are so related to the pivot 32 and to the pivots of the swinging side rod 11 that the cam 27 is given considerable movement in the direction of the arrow, with very little change in its position toward or away from the pivot 36. In other words, the direction of movement of the member 30 during the active portion of its stroke is substantially tangential to the path of movement of the pivot 32. In practice I prefer to open the fuel valve just before the pistons reach their inner dead center position and close it some time after. In some cases the valve will close as much as 30 after said dead center.

In Fig. 3 is shown a slight modification wherein the cam 27 is mounted on the lower arm 25 of the bell crank lever which actuates the fuel valve 19, while the anti-friction roller 26 is mounted on the projection 29 of the'member 30. p The distance between the dotted line 37 and the point of the cam indicates the extent of movement of the arm 25 due to the action of the cam.

By reason of my improved construction it will be seen that I have been able to dis pense with the cam shaft commonly employed with these engines and its bearings together with the driving connection, and also to simplify and reduce the cost of manufacture of the engine as a whole.

My improved arrangement may be situated outside of the main engine casing but I prefer, however, to place it inside of said casing where the parts are subject to the splash lubrication and hence the wear will be slight. By arranging the parts as described, the cost of erecting or taking down the engine is reduced to a minimum. Further by so arranging the parts that the path of movement of the cam is substantially in a straight line and tangential to the path described by the pivot the effect of wear in the joints on the timing of the fuel valve is not magnified as would be the 'case with other arrangements.

As a specific illustration of my invention I have-described the valve cam as being actuated by one of the side rods, but under certain conditions it can be actuated by the main connecting rod. In the case of an ordinary twocycle engine having a single connecting rod'said rod would be utilized to actuate the valve.

In accordance with the provisions of the patent statutes, 1 have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative and. that the invention can be carried out by other means.

What I claim as new and desire to secure by Letterslatcnt of the United States, is:

1.' In an engine, the combination of a cylinder, a piston located iherein, a crank shaft, a swinging connecting rod between the piston and the shaft, a valve, a cam for actuating it, a pair of pivotally connected members which carry said cam and more it to actuate the valve, and pivots for said members, one of which is fixed and the other supported and moved by the connecting rod. In an engine, the combination of a cylinder, a piston located therein, a crank shaft. a wringing connecting rod between the piston and the shaft, a valve, means for biasing it to closed position, a. valve lifter, an actuating means which is moved by the connecting rod, and a cam which is intcrposed between the lifter and the actuatil-ig means, and through which movement is transmitted from the one to the other to open the valve against the biasing means.

In an engine, the combination of a cylinder, a piston located therein, a crankshaft, a rod which connects the piston to the crank-shaft, a Valve in the cylinder Wall, a cam for actuating the valve, and means pivotally attached to the rod for moving the cam to first open the valve and then release it as said rod passes over the inner dead center region of the piston.

In an engine, the combination of a cylinder, a piston located therein, a crankshaft, a rod pivotally connected to the piston and the shaft, a valve in the cylinder Wall, means for closing it, a suitably-shaped actu ator for first opening and then releasing the valve, and means actuated by the connecting rod and pivoted on a stationary part of the engine for bodily moving the actuator over an orbital path to positively open the valve and then permit the closing means to close it.

5, In an engine the combination of a cylinder, a piston located therein, a crankshaft, a rod pivotally connected to the piston and the shaft, a valve, a means for closing it, a suitably shaped cam for first opening therein, a crank-shaft, main and side rods pivotally connected to the pistons and the shaft, a valve, a cam for actuating it, a pair of pivotally connected members for moving the cam, and a pivot for one of said members that is carried by one of the side connecting rods.

7. In an engine, the combination of a cylinder, oppositely moving pistons located therein, a crank-shaft, main and side rods pivotally connected to the pistons and the shaft, a valve, a cam for actuating it, a pair of pivotally connected members which move the cam, means for adjusting the cam to change the timing of the valve, and pivots for said members, one of which is fixed and the other supported and moved by one ofthe side rods.

8. In an engine, the combination of a cylinder, oppositely moving pistons located therein, a pulverizer for introducing fuel into the cylinder between the pistons, a controlling valve therefor, a crank-shaft, swing ing rods connecting the pistons and shaft, a

lifter for the valve, pivotally connected members, a pivot attaching one of the members to, a rod, and a device carried by the memberswhichacts on the lifter when one of said members is moving in a direction substantiallytangential to the orbital path of one of its pivots.

In witness whereof, I have hereunto set my hand this 31st day of December, 1912.

. WILLIAM EVERETT VER PLANCK.

Witnesses:

DORMAN WEAVER, .I. W. HUGHES.

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