US1901571A - Steam engine - Google Patents

Description

March 14, 1933. H. s. VINCENT 1,901,

STEAM ENGINE I Filed Aug. 6', 1927 2 Sheets-Sheet l g-nvemtoz March 14, 1933. a VINCEN 1,901,571 I STEAM ENGINE 'Filed Aug. 6, 1927 Z SheetS-Sheet 2 mvgmoa ATTORNEYS Patented Mar. 14, 1933 I UNITED s'r-Ares PATENT. OFFICE EABBY 8. VINCENTQOF BIDGEWOOD, NEW JERSEY, ASSIGNOB 1'0 FRANKLIN BAIi-WAY SUPPLY comm, OF NEW YORK, N. Y A CORPORATION OF DELAWARE s'rnm ENGINE Application filed August 6, 1927. lerial No. 211,051.

lmake conveniently possible, especially with a poppet-type valve, an early cut-off of steam without loss of power in starting and at slow speeds. With this object in view the invention is particularly useful in loco- 1 motives and will be hereinafter shown and described as applied to a'locomotive valve similar to the Lentz poppet type.

More specifically my invention contemplates the attainment, in a poppet valve.

with its advantage of quick movement to full open and closed positions, of early cutofi of the main portion of the steam supply,

along with an extended cut-off of a limited portion thereof which in starting and at slow speeds gives the effect of a late cut-ofi'.

Another object of the invention is to provide mechanism to attain the foregoing advantages, which shall be positive in operation, simple in construction, and readily applicable to existing poppet-valveequipment. How I attain the foregoing, together with such other objects and advantages as are incident to my invention or will occur to those following description taken together with the accompanying drawings, in which:

Figure 1 illustrates in longitudinal vertical section the upper portion of a cylinder and a steam chest mounted thereon, the latter having positioned therein the valve mechanism embodying the present invention, with certain cam parts exaggerated in their proportions for purposes of illustration; and v Figure 2 is an enlarged view of the cam mechanism shown in. Fig. 1, indicating the true proportions of the cam and the operation thereof.

It will be understood that the mechanism shown is for admission of the steam to the cylinder 2, the exhaust valves being in a separate chamber of the'chest 3, to one side of the admission valves, and exhausting through outlets indicated at i, at, but the exhaust valve mechanism is not shown since skilled in the art, will appear from the it forms no part of the present invention. At 212 and 36 I have indicated a cylinder lubrication pipe and a cam chamber drain.

As shown in Fi 1, steam is admitted to the chamber 5 'of the chest 3 through inlet 6. Near the ends of the chamber are annular valve members 7, 8, one for each end of the cylinder, each valve having edges or flanges 9, 10, adapted to seat, respectively on the annular valve seats 11, 12. These ring-like valves 7, 8, are supported, as by webs 13.

and collars 14, on reciprocable rods or shafts 15 and 16, respectively, and held as against endwise movement on said rods by shoulders 17, and rings and lock nuts 18 and 19. Since the diameter ofthe flange 9, of each valve, is greater than the diameter of its flange 10, the steam pressure in chamber 5 will tend to hold the Waive-in seated position, the position shown at the right of Figure 1. The steam, having access also .to the spring chambers 20, 20, will act on the outer ends of valve-stems 15, 16, tending further to hold the valves in closed position. To insure the proper closing of the valve, particularly, when the steam is oil, a spring 21 is inserted in each chamber 20, such spring bearing on the outer side of ring 18', the compression thereof being adjustable by means of a screw 22 and locknut 23. I

When a valve is open the steam passes The shaft is rotated back'and forth by any suitable crank or arm (not shown) connected to the usual valve motion mechanism of the locomotive. The valve rods or stems 15,1h, bear, through the intermediation of rollers 29, 30, on the outer surface or periphery of the stepped cam member 26, and are mov able longitudinally in bushings 31. When the portion 32 of the cams surfaCe'I,(whi -ch is farthest from its axis) engages'feither roiler,-- A

the respective rod is forced".ioutwardsjaiid',

, valve will be adjacent the portion 33 of the to cams surface (which is nearest its axis) cut-01f occurs when the rollers 29, 30 'envalve 7 will be wide open. 'When the piston f th str ke,

is this period the roller 30 is on the portion 33 the valve is opened wide giving free admis- 33, the actual diflerence,'in practice, being sion of the steam to the respective cylinder about .OLof an inch.

end. At such time the roller of the opposite be such that at high speeds the effective The operation, in brief, will now be seen and the corresponding valve will be closed. gage the respective cam surfaces 34a, 34b,

Assuming, now, that the piston 2a in cylwhile at starting, and when the engine is I inder 2 is at theleft end and is about to running at slow speeds the slight opening.

move to the right, and that the valve motion at the valves, caused by the cam surfaces of the locomotive is set to give a cut-off of 34a and 346, will be sufiicient to ro'vide the 50%. The roller 29 will be bearing on the necessary power, providing, in e ect, an exportion 32 of th urfa of the cam and tended cut-off up to any desired percentage for example 7 5 or 80 per cent.

has moved to the center of it stroke, i. .e. It will t e e a y y pr v 50%, the cam will have been. turned to the ment, a short limited cut-oil may be used right until the roller is in'engagement with with a poppet admission valve, while at the intermediate cam surface 34a. This is the same time obtaining, in eflect, a long the point of normal cut-ofi; at running c t-oil for starting and slow-speed running; speeds, but-it-will be seen that the valve 7 l o that the device is simple, positive in is till rack d op n, and for tartin or operation, and inexpensive to construct; and

slow running, steam will enter the cylinder that the improved cam construction may be through the crack and build up a pressure eadily applied to existing suflicient to move the locomotive. During ms of valve equipment. What I claim is of the cams surface, and valve 8 remains I Valve m nism of the character closed. As the piston moves farther to the described, a p pp v lve, a stem pr, right, the cam will turn until, for example and an oscillatory actuating ca n engaging at 75% of stroke, the roller 29 is on the porthe Stem, Sald havlhg lts ehgaglhg {io 33 f th cams surface d valve 7 face constructed -w1th three stepped portions poppet or other 0 ill b t d U f th movement at respectively different distances from the roller of valve 8 will. bear on surface 34?) axis, one of which Portions holds the of the cam, opening the valve slightly, which Valve in full p PQ during a P i will cause preadmission of steam to' the of the m Osclnatloh, the next of Whlch right hand end of the cylinder which escapes Portions holds the va -p t y p 35 through the right hand exhaust valve (not a thehexh succeeqlmg P P the h S -Shown) While i exhaust Valve is Open, oscillation, and the-third of which portions and cushions the piston when such exhaust Permlts complete 9 ohthe Valve valve closes. As the cammoves farther to thanext succeedlhg P01131011 of the cams the right, roller 30 will engage portion 32 osclnatloni of the cams surface and valve 8 will be open In F p Valve Steam admlsslon mach wide, at whicfi time the piston is at the right anism o the character described, a valve, a hand end'of cylinder 2 and ready for the reseat therefor, and a cam havmg a Stepped turn stroke to the left. The entire operation Surface with a Portion adapted to hold Said.

is then reversed, main cut-off for the right Valve from its an adjaicent portion hand end' occurring when roller 30 engages adapted to Permlt only a Partlal movement tion 33 of the cams surface.

For clarity of illustration only,

. ed in Fig. 1, the crack at valve s hown correspondingly greater than it is in actfial practice. and 346 only slightly higher than surface surface 346, at which time the piston, in the example given, has travelled half way to the left, and complete closure of valve "8 occurring when the roller 30 again rides on por- It will thus be seen that astepped orinterrupted movement of the valve mechanism, corresponding to the steps of the actuating cam, is obtained'. i

. The foregoing operation of the valves with regard to themovement of the cam will i Fig. 2.

the cam surfaces or steps 34a and 346 are exaggerat- 7 being Fig. 2 shows surfaces 34a of the valve toward its seat, and a portion adjacent said second-mentioned ortion adapted to permit seating of the va ve.

"3. In limited cut-off steam en 'ne mech-' anism of the character described aving cylinder and piston, valve means, and a triplestepped actuating means therefor constructed to control said valve means by stepped movements, said stepped actuating means including means adapted to produce a momentarily substantially fixed valve opening v v of relatively small area during partial movebe particularly :clear from inspection 'of ment of the piston, whereby to provide an controlling means including means adapted to hold said valve in open position, means ada ted to permit only a partial movement of t e valve toward closure of-said port, J means for holding the valve at an intermediate constant opening during artial movement of the piston and means a a ted to permit movement of the valve to y closesaidport. r 10 5. In a steam engine having a cylinder and piston, a valve a movable cam devicefor actuating said valve, said cam device v including means for holding said valve in open position during a portion of the piston 15 stroke and cam movement, means step d from said first-mentioned means for hol mg said valve 0 n at. a constant lift during a further portion of the piston stroke and cam fmovement, and means stepped from said so second-mentioned means for fully closing said valve durin a still further portion of the piston stro e and cam movement.

In testimony whereof I have hereunto signed'my name.

- as HARRY -s. VINCENT.

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