US2218824A - Valve mechanism - Google Patents

Description

VALVE MECHANI SM INVENTORS ATTOR N EYS Oct 22, 1940 J. J. KUPKA r A1. 2,218,824

`VALVE MECHANISM Filed Nov. 12, 193s 3 Sheets-Sheetv 2 ...IMT

ATTRNEYS 'A -Oct, 22, 1940-` J. J. KUPKA Er A1.

VALVE MECHANISM Filed NOV. 12, 1936 5 Sheets-Sheet 5 Patented on. 22.1940

UNITED STATES z,21s,s24 VALVE MEcnANrsM JohnJ. Kupka, New Brunswick,v N. J., Gordon T. Wilson, Bnifalo, N. Y.-

Application November 12, 1936, Serial No. 110,516

4 Claims.

The present invention relates to locomotive l steam engines and more particularly to the valve operating mechanism for same, and has for its primary object the provision of an improved valve mechanism by which to increase the operating efllciency of the engine.

In the conventional type of locomotive now in common use the steam engine fory same includes a reciprocating slide or piston valve controlling the inlet and exhaust ports of the engine, the

valve having a total lineal travel considerably in excess of the actual travel required to move the valve relative to the ports, the added travel being required to provide a portion of the cycle in which the valve comes to rest and begins its reverse action movement. Such operation is required in order that the valve, in its Aoperation relativeto the steam ports, maybe moved at a rate of travel commensurate with the time allotted for the entrance and exhaust of the steam to or from the power cylinder.

In view of the above a more specic object is to provide, in a locomotive valve mechanism, means for accelerating and decelerating the reciprocating motion of the engines valve so as to permit the entrance and exhaust of the pressure steam at the critical instants required to afford a high degree of eiilciencylin power output.

Another object is to provide an accelerator valve mechanism. for locomotive steam engines and the like which in operation functions to materially reduce the total travel of the engine valve, effecting thereby an appreciable reduction in the size and wear of the moving parts particularly the valve and housing for same,

consequently providing a valve operating mechanism capable of extended uninterrupted service by partially obviating the necessity for the usual 50 necton with the accompanying drawings which form part of the application.

In the drawings: f Fig. 1 is a side elevational view of the engin mechanism of a typical locomotive incorporat- 55 ing therein the valveaccelerator mechanism, portions ofthe apparatusr being shown in central section.

Fig. 2 is an enlarged detail view of the valve accelerator mechanism, being a longitudinal sectional view thru same.

Fig. 3 is a transverse section taken kon line 3-3 of Fig. 2.

Fig. 4 is a horizontal section taken on line 4 4 of Fig. 3.

Fig. 5 is a fragmentary perspective view of the 10 main elements of the accelerator mechanism; and

Figs. 6 and'l are diagrammatic views of the valve accelerator mechanism shown in two positions assumed during the cycle of operation.

By reference to Fig. l it `will be apparent that the engine valve accelerator mechanism is illustrated as being adapted to the conventional type of locomotive steam engine comprising a power cylinder 8 in which is slidably carried a drive 20 piston 9 having a pistonrod I0 extending therefrom. The piston rod I0 at its opposite end. is secured to a cross head II` slidably carried for reciprocating movement von guide bars I2, the latter being xed to a guide bar yoke or frame 25 I3. To the cross head II is flexibly connected a main drive rod I4, -the opposite end of which is connected to a crank pin. carried-on the driving wheel I5 of the locomotive for driving the same. The power cylinder 8 and its associated 30 piston 9 are of the conventional double action type, being adaptedl to impart power to the driving wheels during either direction o! travel. Steam from the locomotive boiler is introduced at high pressure to theA engine thru a supply pipe 35 I6,.the discharge of the steam to the cylinder 8 being controlled by a piston valve Il. In View of the double action of the power cylinder8 the valve I1 comprises two spools I8 functioning, during their sliding action, to open and close entrance ports I9 communicating with the respective ends ofthe power cylinder 8. The actionof either spool I8 of the valve I1 relative to the respective entrance ports I9 serves to first admit steam into the power cylinder by be- 'ing disposed to one side of the port I9, and

thereafter to permit the exhaust of the steam thru the respective exhaust ports 28 by being disposed toward the -opposite side of the entrance port I9 after a suitable period for the ex- 50 pansion of the steam in imparting power to the piston 9. l

In the conventional type of locomotive engine ay combination lever 2l is provided for actuation of the valve I1,'the lever 2I being flexibly cou- 55 pled at one end to the cross head II by a union link 22. Actuation of the valve I1, in the conventional type of valve mechanism in common use, is eiIected thru the combination lever 2I to a valve stem 23 extending from the valve I1, the valve stem 23 being, in this instance, flexibly connected to the lever 2I. The combination lever 2| in actuating the valve I1, is fulcrumed at 24 on an end of a radius bar 25, the opposite end of which is flexibly secured to a block 28. The block 28 is adjustably retained in a rocker link 21, the position of the block 28 therein being moved to the desired setting by operation of a lifting link 28 connected thereto, the lifting link being actuated by an arm 28 carried on a reversing shaft 30 from which extends a reversing arm 3i.

The rocker link 21 is swingably carried on the frame I3 and is actuated in a rocking motion by an eccentric rod 32 flexibly coupled 'therewith and actuated at its free end by association with an eccentric pin on the driving wheel I5. By adjusting the block 26 to various positions within the rocker link 21 the power of the engine is varied, the adjustment being effected by operation of the lever 3I. The block 26 being positioned toward one end of the rocker link 21 serves to actuate the locomotive in the forward direction, the block 26 being positioned toward the opposite end of the rocker link 21 serving to reverse the direction of the locomotive.

The association and cooperation of the various elements comprising the steam engine particularly the connection of the combination lever 2I to the-valve stern 23, thus far described, being of the conventional type, are well known to those skilled in the art. that the valve I1 being so operated must be reciprccated an appreciable distance during a cycle of operation of the engine so that each of the spools I8 thereof are moved to and from registry with its entrance port I9 at a travel commensurate with the required perfomance of the engine. That is, the spool I8 in moving to open the port I9 must travel at a speed so that the port I9 is opened or closed in a minimum of time. This prerequisite necessitates an excessive travel of the' valve I1 so that ample time is afforded for reversing the travel of same, which is accomplished by moving the spools I8 apprecably beyond their normal path of travel until the reverse action is attained. To obviate this objection, specifically by reducing the required travel of the valve I1, the accelerator mechanism 34 is provided.

A detailed description of the valve accelerator mechanism 34 now follows during which attention is particularly directed to Figs. 2, 3 and 4. The numeral 35 indicates an accelerator cam flexibly connected at one end to the combination lever 2i, the oscillation of the latter serving to imparta reciprocating action ,tothe cam 35. The cam 35 is slidably carried onavslide plate 36 in conjunction with a guide frame-.31 fixedly secured to the frame I3. The cam 35 comprises a substantially flat intermediate area 38r terminating at each end in inclined portions 33 and 48. A rocker lever 4I of substantially T-shape valve stem 23. The arms 42 are provided with` rollers the latter being in contact with the cam surface of the accelerator cam 35. 'I'he It is to be noted, however,

rocker lever 4I is mounted for rocking movement on a shaft 43 fixed to the guide frame 31.

In considering the operation of the entire valve mechanism with reference to the actuation of the valve I1 a clearer understanding of same will be had by observing the functioning of the accelerator lever 4I in cooperation with the combination lever 2i. Movement of lever 2i, as previously described, serves to actuate the accelerator cam 35 in a reciprocating action, the extent of the travel being variable by adjustment` of the block 26 in the rocker link 21. The accelerator mechanism 34 serves primarily to accelerate the travel of the valve I1 during opening of same and correspondingly to accelerate the travel of same during closing relative to the respective ports I8. By reference to Fig. l it may be assumed that the spool I3 is being moved to open the port I8, the opening being accomplished in a short interval of time. At the start of operation, the rocker lever 4I is disposed in central position having both of its rollers 45 in contact with the respective inclines 33 and 40. As the accelerator cam 35 is slid in one direction'the rocker lever 4I immediately assumes an angular position as'illustrated in Fig. 6 so that'the spool yI8 is rapidly moved beyond the port I8 to admit steam therethrough. The cam 35 continues to slide as the pressure steam is admitted in the power cylinder 8 during which the cam is disposed substantially as shown in Fig. '1. By comparison with the showing in Fig. 6, it will be noted that the rocker lever 4I has maintained its angular position from winch it will be apparent that the valve I1 is heid in full open position during this cycle. Upon slid- Y of the engine by minimizing the time required l to open and close the controlling valve. In that the valve of the improved mechanism may accomplish its function during a shorter travel the power required to overcome the inertia is minimized thereby effecting a reduction in the wear of the associated mechanism.

The co-reiation of the accelerator mechanism 34 to the combination lever 2I as illustrated in Fig. 1 permits of arranging the valve I1 in close association with the power cylinder 8 without reducing the effective stroke of the valve, in that the accelerator cam 35 is coupled to the combination lever 2| beyond the connection of the radius bar 25 thereto thus reducing tol a minimum the objectionable clearance space between the power cylinder and the piston valve. The invention also makes it possible to increase the effect of the rocker link 21 on the cam 48 by arranging the connection to the rocker link 21 thru the radius bar 25 so as to be intermediate the ends of the combination lever 2 I.

In the preferred embodiment of the inventionv illustrated in the drawings the conventional typev of valve actuating mechanism is employed to operate the slidable-cam 35 of the accelerator mechanism 34, in that same permits of incorporating the invention with the locomotive mechanisms now in common use. It will, however, beappar ent thatthe invention may be adapted for use in combination with other types of actuating mechanisms without departing from the spirit of the invention, the mechanism including suitable means for controlling the power of the engine by synchronous movementof the fulcrum 24 of the combination lever 2| so as to vary the stroke of the cam 35.

It is to be understood that this -improvement is capable of extended application and is not conned to the exact showing of the drawings nor to the precise construction described and, therefore, such changes and modifications may be made therein as do not affect the spirit of the invention Y nor exceed the scope thereof as expressed in the appended claims.

What is claimed as new is:

1.- Valve operating mechanism for pressure actuated engines including a power cylinder and a piston slidable therein, comprising in combination therewith a slide valve for control or pressure to or from said piston, a rockable lever fulcrumed on said engine and comprising opposed arms extending from said fulcrum and a valve arm depending from said lever and connected to said valve for actuating same, a slidable flat cam having synclined portions for engagement with said opposed arms, and means operable by movement of said piston for reciprocating said cam, and comprising a combination lever flexibly connected respectively to said piston and said cam.

2. In a locomotive engine including a steam actuated power cylinder having a piston slidable therein and a valve for control of steam to or from said cylinder, valve operating mechanism comprising a combination lever connected to said piston, a rocker link oscillated by travel of said locomotive, a block adjustably carried in said rocker link, a radius bar carried on said block and forming a fulcrum for said combination lever, a rockable lever fulcrumed on said engine, a slidable-at cam actuable by said combination lever for oscillating said rocking lever whereby to slide said valve at varying rates of travel in control of steam to or from said power cylinder.

3. In a pressure actuated engine having a power vcylinder and power piston slidably mounted therein, a slide valve controlling the inlet and outlet ports of said power cylinder, said valve including a cylinder having outlet and inlet ports formed in the walls thereof and a valve element slidable in said cylinder and registerable with said ports whereby they can be opened or closed by varying the position of said element, the mechanism for operating said slide valve comprising a at sliding member having a synclined cam face formed on one surface thereof, means for imparting reciprocating movement to said sliding member comprising a lever system associated with said power piston and said member, and a T-shaped rider element engaging with the cam surface on said sliding member and reciprocably actuating the Valve element in said slide valve.

4. In a pressure actuated engine having a power cylinder and power piston slidably mounted therein, a slide valve controlling the inlet and outlet ports of said power cylinder, said valve including a cylinder having inlet and outlet ports formed in the walls thereof and a valve element slidable in said cylinder and registerable with said ports whereby they can be opened or closed by varying the position of said element, the mechanism for operating said slide valve comprising a iiat sliding member having a synclined cam face formed on one surface thereof, means for imparting reciprocating movement to said sliding member comprising a lever system associated with said power piston and said member, whereby the movement of said member is directly and arithmetically proportional to the movement of said power piston during the entire cycle of oscillation of the latter, and a T-shaped rider element engaging with the cam surface on said sliding member and reciprocably actuating the valve element in said slide valve, the movement of said valve element during actuationof the power piston being characterized in that the movement of the valve element is always other than directly and authentically proportional to the movement of the power piston, and that during a portion of the cycle of movement of the power piston, the valve element is maintained substantially stationary.

JOHN J. KUPKA. GORDON T. WILSON.

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