US1577665A - Starting valve for engines - Google Patents

Description

latentt-mil lidar. 23, 1926.

UNITED stares PATENT OFFICE.

WESTINGI-IOUSE ELECTRIC PENNSYLVANIA.

ANI) MANUFACTURING COMPANY, A CORPORATION OF i STARTING VALVE FORIENGINES.

Application Afiled October 30, 1920. Serial No. 420,664.

To LIZZ whom t may concern.'

Beit known that I, RICHARD E. B. WAKE- FIELD, a citizen of the United States, and

a resident of Philadelphia, in the county of' Philadelphia and State of Pennsylvania,

have invented a new and useful Improvement in Starting Valves for Engines, of which the followingvis a specification.

My invention relates to internal combustion engines and it has particular reference to air starting mechanisms for multi-cylinder internal combustion engines ofthe Diesel type.

An object of my invention is to provide an efficient starting mechanism for multicylinder internal combustion engines and more particularly for engines of the Diesel type in which air under pressure is used for starting the engine.

A further vobject of my invention is to provide an improved and efficient unit construction in an `air starting mechanism so constructed that ka multi-cylinder engine embodying any number of cylinders may be readily equipped with my improved starting device without modifying the design of the operating mechanism.

,A further object `of my invention is to produce an .air starting valve simple in operation, durable in construction and automatic in action. Y

These and other objects which will be made aparent throughout the following description are attained by means of apparatus r embodying the features of my invention herein described and illustrated in the accompanying drawing in which:

Figure 1 is a longitudinal sectional vie-w of a'valve structure applied to the head of an internal combustion engine and embodying a preferred form of my invention; Figure 2 is a detailed sectional view on the line II-II of Figure 1, and Figure 3 is a diagrammatic plan view, showing the appliengines, the design of the starting mecha-r vis constructed upon a cation of my invention to a multi-cylinder nism must be modified for any given number of engine cylinders. My improved device Y unit plan and is designed 1n such a manner that a multi-cylindere'ngine of any number of cylinders may be equipped with my air starting device by associating a unit valve with each engine cylinder, of the several cylinders from a single manifold and operating the valve movements from a single cam shaft. The reciprocating portions of the air valve are constantly in motion but are held out of Contact with the air admission valve stem' until air under pressure is admitted to the valve. The air acting vupon a reciprocable piston throws the reciprocating parts of the valve in contact with the air valve stem and permits theopenlng of the air valve to be controlled from the cam shaft. This provid-es an automatic operation of the air valves of a multicylinder engine which is controlled by the manipulation of a single valve supplying air `to the air manifold.

Referring to Jche drawing, 10 designates a cylinder head to which is'secured a closure plate 11 provided with a central opening 12. A cylindrical vvalve casing 13 is mounted upon and may be integral with the closure plate 11. The casing 13 has a iianged upper portion 14 which is securedlto a cooperating ilange 15 of an upper cylindrical plunger casing 16. Within the valve casing 13 a piston 17 is mounted to reciprocate. A

valve stem 18 rigidly connects the piston 17 with a valve 19 which is arranged to open inwardly into the engine cylinder. The valve 19 isnormally held closed by a spring 2O which is arranged to bear against the piston 17 and cover plate 11. The valve stem 18 projects through the piston 17 forming an abutment, the purpose of which will be hereinafter described.

Anl arcuate chamber 21 is formedbetween the flanged members 14 and 15, within which is mounted a disc 22. A 'stem 23 extends in slidable relation through the disc 22, and is splined to the disc 22 as by a key 24 to prevent relative rotation between the disc and the valve stem. The upper portion of the stem 23 is provided with a threaded portion 25 which operatively engages a threaded portion of a plunger 2G. The plunger 26 and stem 23 are normally held supplying air to the unit valves in an upper position by a spring 27, which bears against the disc 22 and plunger 26. The plunger 26 is provided at its uppermost end with a reduced portion 28 which er? 'be `actuated through a linlr 32 and cam 33,

the latter being 'secured to a cam shaft 34. The cam shaft 34 may extend the length of the engine and serve to operate the starting valves in all the cylinders by means of in.

dividual cams 33 secured thereto and adjusted to actuate the operating mechanism of the respective starting valves in proper timed relation. It may be preferable, however, to provide a separate cam shaft 34 for each cylinder.

Y fluid-tight relation Air is supplied to the casing 14 and chamber 21 from a manifold 35 which is disposed adjacent to the air valves of all of the engine cylindersandwhich is preferably provided with an air supply valve 36. The manifold 35 communicates with the valve casing 13 through a conduit 37 and with the arcuate chamber 21 through a conduit 38. Secured'to the disc 22-and extending within the chamber 21 is a flange or piston 39 which forms an integral part vof the disc 22. The flange 39 is constructed to oscillate in within the arcuate chamber 21 and is normally held near one end of the chamber 21 by means of a helical spring 40 which serves to press the flange 39 against a stop 41. Air may b-e supplied to the manifold 35 from any suitable source of compressed air through a conduit 42 and may be exhausted from the manifold 35 by turning the valve 36 to communicate with a conduit 43 which is open to the atmosphere.

Having described the arrangement of the device embodying myinvention, thevoperation thereof is as follows: Air under pressure is admittedby the manipulation of the valve 36 to the manifold 35 and thence to the casing 13 and to the arcuate chamber-21. The air acting on one side of the flange `39 overcomes the force of the lspring 40 and causes the disc 22 and with it the valve stem 23 to move through an angle determined by the length of the arcuate chamber 21. The angular movement of the stem 23 within the plunger 26 causes the stem 23 to be downwardly displaced to contact with the upper end of the stem 18 ofthe valve 19, in which position the reciprocating movements of the plunger are communicated to the air valve 19 so as to open and close the air valve in timed relation to the movement of the engine piston. It is to be understood that when the cam 33 is rotated a constant -reciprocation of the lever 29, plunger 26 and stem 23 is effected. It follows that when the engine is at rest, t-he lever 29 retains the plunger 26-and stem 23 in one or more of the engineV cylinders in their lower position. At the time air is admitted to the manifold,'the stem 23 is still further lowered by the rotation of the disc 22 in a manner described above. This results in the openingk of an air valve in the cylinder, or cylinders, in which the plunger 26 and stem 23 are at the time of starting held in a lowered position. Air is thus admitted to a cylinder in which the pistonV is in a position to be forced outwardly. As the engine turns over, other cylinders will in turn receive a charge of starting air in a similar manner. Vvhen the engine is in full operation, a turning ofthe single valve 36 to register with the exhaust 43 permits the spring 40 to return the flange 39 anddisc 22 to their normal position a's determined by the stop 41, thereby raising the plunger 26 and the stem 23 so that in their further 'reciprocation they will not contact with the valve stem 18. The spring 2O insuresv that the air valve 19 will be closed at all'times, except during those periods vin which' air is supplied to manifold 35.

My improved starting valve is especially advantageous in that it may be applied to multi-cylinder engines of any type without the use of complicated operating mechanisms exterior to the valve structure. This is made possible by providing for cachengine cylinder an.` individual and complete starting mechanism. `It follows that the failure of one valve to operate-inno way interfered'with the operation of the valves in the remaining cylinders. This construc-` tion has the further advantage inthe readiness with which any valve may be `removed for repair or replacement, such exchange of valves Vbeing readily accomplished without interfering with the starting mechanismof the remaining engine cylinders.

TWhile I .have shown my invention in but one form, it will'be obvious Ito those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications, without departing 'from the spirit thereof and I desire, therefore, that only such limitations shall be placed there-l upon as are imposed by the prior art Vor as specifically set fort-h inthe appended claims.

l/Vhat I claim is: i

1. An automatically extensible push rod for air valves comprising a stem provided with a screw, a. non-rotatable nut cooperating with the screw, an air motor adaptedto rotate the stem in one direction, and spring means to return the stemto its initial position.

2. In an air starting mechanism for internal combustion engines, a reciprocating plunger, means operatively connected to a moving engine part for reciprocating the plunger, an airvalve arranged to be opened and closed by the reciproeation of the plunger, and means for changing theI etfective length of the plunger, the plunger being so disposed with relation to the valve that when the ei'ective length of the plunger is increased the valve will be opened by the reciprocatio-n of the plunger, and When the A plunger is at its shortest effective length, the

valve will not be opened by the reciprocation of the plunger.

3. In an air starting mechanism for 1nternal combustion engines, a reciprocating plunger, means operatively connected to a moving engine part for reciprocating the lunOers. an air valve. arranoed to be ooened b l b and closed by the rcciprocation of the plunger, a casing `tor the valve, means for supplyng compressed air to the casing, and means for changing the effective length of the, plunger, said means comprising a pressure responsive device so arranged that when air is admitted to the valve casing the effective length of the plungervvill be greater, the plunger being so disposed With relation to the valve that When the effective length or the plunger is increased the valve Will be opened by the reciprocation of the plunger,

and when the plunger is at its shortest er"- fective length, the valve will not be opened by the reciprocation of the plunger.

4. An automatically eXtensible push rod for air valves comprising a stem provided with a screw and adapted to open the valve, a non-rotatable nut cooperating with the screw, an air motor adapted to rotate the stem in one direction, spring means to return the stem to its initial position, and spring' means opposing the valve-opening movement of said stem.

In testimony whereof, I have hereunto subscribed my name this 29th day of October, 1920.

RICHARD E. B. VVAKEFIELD.

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