US2281818A - Railway locomotive piston valve inertia arrester - Google Patents

Description

May 5, 1942. c. G. ASH 2,281,818

RAILWAY LOCOMOTIVE PISTON VALVE INERTIA ARRESTER Filed Jan. 16, 1941 3 Sheets-Sheet l INVENTOR.

E. 31: 1 El... Ash

ATTORNEYS.

y 1942- c. G. ASH 2,281,818

RAILWAY LOCOMOTIVES PISTON VALVE INERTIA ARRESTER Filed Jan. 16, 1941 3 Shets-Sheet 2 FIG. 3.

FIG. 4.

INVENTOR.

C. ELI-'1 El. Ash

ATTORNEYS.

y 1942- c. s. ASH 2,281,818

RAILWAY LOCOMOTIVE PISTON-VALVE INERTIA ARRESTER Filed Jan. 16, 1941 F IG. 5.

3 Sheets-Sheet 3 INVENTOR.

Earl l3. Ash

ATTORNEYS.

Patented May 5, 1942 RAILWAY LOCOMOTIVE PISTON VALVE INERTIA ARRESTER Carl G. Ash, Pomona, Calif.

Application January 16, 1941, Serial No. 374,741

6 Claims. (Cl. 121-161) This invention relates to improvements in means for arresting the inertia of railway locomotive piston valves.

The'primary object of this invention is the provision of improved means for cushioning the shock of the steam control piston valve of railway locomotive driving equipment incident to stopping, starting and reversing of the piston valve whereby to do away with many of the troubles incident to present day locomotive rail- 1 way piston valve operation.-

It is well known to those skilled in the art relating to railway locomotive driving and operating mechanism that the shock incident to operation of piston valves occasions frequent failure 1 of parts of the valve gearing; causes excessive wear or the pins and bushings of the valve gear and other operating equipment; causes excessive trouble with the reverse gearing, and is a direct fault of many accidents to life and property. It

is the purpose of my invention to arrest the inertia of the piston valve with an improved cushioning arrangement at each end of the travel stroke or the valve, workingat short travel at highspeed, whereby the above mentioned deficiencies or conventional railway locomotive operation will be overcome; the locomotive action will be more efiicient and there will be a substantial saving in fuel and water consumption, by better control of cut oil at speeds.

Other objects and advantages of this invention will be apparent during the course of the following detailed description.

In the accompanying drawings, forming a part of this specification and wherein similar reference characters designate corresponding parts throughout the several views.

Figure 1 is a fragmentary view,-partly in section, showing the valve gearing and drive connections of a conventional steam railway locomotive, with my improved inertia arrester associated therewith.

Figure 2 is a cross sectional view taken thru a ,railway locomotive piston valvein association with the main piston. assembly of the locomotive, and showing my improved inertia arrester associated therewith, for a short travel of the piston valve, with the valve in forward position;

Figure 3 .is a view of parts similar to that shown in Figure 2, but with the piston valve in rear position, for short travel.

Figure 4 is a cross sectional view of the parts shown in Figure 2, but with the piston valve arranged ior full length travel, with the valve in forward position.

Figure 5 is a cross sectional view of the parts shown in Figure 4, but with the piston valve in position for full travel, and in rear position.

Figure 6 is a longitudinal cross sectional view taken thru the steam control piston valve and showing its association with improved inertia arrester pistons.

In the drawings, wherein for the purpose is shown only a preferred embodiment of the invention, the letter A may generally designate a railway locomotive which may include a main piston assembly B connected with means C to drive the wheels D of the locomotive. A piston steam control valve assembly E is provided in association with the main piston cylinder for control of steam with respect thereto, as is well known to those skilled in the art. In association with the piston valve E and the driving means C, there is provided valve gearing F of any approved type (Baker shown inthedrawings) In connection with the piston valve mechanism I associate my improved inertia arresting means G.

The main piston Ill of the piston assemblage- B operates within a cylinder II and is provided with a piston rod l2 connected with a convene tional cross head l3. The latter has connected therewith a connecting rod l4 forming part of the-drive means 0, which is connected to the main crank l5.

The body or piston valve of the piston valve assemblage E operates within a cylinder 2| having bushings or liners 22 and 23 within which the piston valve enlarged ends 24 and 25 of the piston valve, upon which there is admission and exhaust rings, respectively operate to control steam ports 21 and 28 respectively for operation of the main piston of the locomotive, in a manner which is purely conventional.

Thevalve gearing'F includes a valve rod 30 pivotally connected to a combination lever 3|; the latter in turn being connected with a valve stem cross head 32 which is connected by a suitable rod 33 with the piston valve body 20, in a manner to be subsequently described. The valve rod 30 is-pivotally connected with a bell crank 35 and Wm suitable reversing yokes 38v is connected with a gear reach rod 31; This bell crank tensions 60 and it upon the ends of the usual piston valve cylinder 2|. To accomplish this the cap plates at the ends of the usual piston valve cylinder are removed and the inertia piston cylin-' ders 50 and 6| are secured by means of studs or bolts 62 in the usual cap plate attaching bolt openings. ,The cylinder 6| may be referred to as the forward inertia arresting cylinder and it may have a cap plate 53 secured in place by bolts;

Referring at this time to a detailed descripv tion of the piston valve construction and assemblage, the valve body 20 is provided with enlarged ends 24 and 25 each having the piston valve admission and exhaust rings. The valve body itself ,is hollow. The valve stem piston rod 33 is extended thru suitable hubs 20a attached in spider-like manner to the enlarged ends of the piston body 2!). Suitable sleeves Hand 13 are provided upon the rear and fore ends of the valve stem piston rod 33, and on the extreme forward end of the latter, at the end of the sleeve 13 there is provided a cushioning-pr inertia arresting piston 15, which is relatively thin and externally provided with a piston ring thereon. The sleeve 12, whichis preferably of the same length as the sleeve 13 at its rear'end is similarly provided with a cushioning or piston valve inertia arresting piston head 16 of the same construction as the cushioning piston 15. An integral flange." on the rod 33 holds the valves 20, H and 16 in a definitely spaced rigid a.ssem-. bly, such as shown in Figure 6.

The piston valve 20 of course, operates only in the piston valve chamber cylinder 2| and controls the ports 21 and 28. On the other hand, the cushioning pistons 18 and respectively operate in the chambers of the inertia arrester. cushioning cylinders 60 and 6| respectively.

It is to be noted that the cylinders 60 and 6| provide cushioning compartments therein between the end plates 65 and 63 thereof and the cushioning pistons which operate respectively therein. Each cylinder 60 and 6| is, however, provided with a by-pass. These by-passes are indicated at 80 and 8| respectively for the cylinders 60 and BI, and they have conduits which I connect in the chamber of their respective cylinand in another position closes the line 81 fromthe reservoir 88 and opens the line 81 between the valve 89 and the by- pass valves 83 and 84 to an escape nozzle or opening 90 provided in the casing of the valve 89 so that air under pressure in the line 81 may be exhausted therefrom and allow valves 85 to'be unseated, thereby establishcommunication between outer ends of inertia cylinders and the exhaust passages K, allowing steam in cushioning end of inertia cylinder to pass to exhaust passage, when its locomotive is working at long valve travel, as at low speed, and

cushioning is not desired.

In conventional railway steam locomotive operation, it is customary through the valve gearins to provide for a long piston valve travel, such as when starting the locomotive with a heavy train, or when pulling the load of the train over heavy grades. provided when the locomotive approaches top speeds. .For short valve. travel of the piston valve 20 cushioning effects are provided by, the cushioning pistons 15 and 16, according to the length of the travel in their respective pistons,

but for long piston valve travel, since the cushioning pistons 15 -and I6 closelyapproach the end plates 63 and 65 respectively associated therewith, meansis provided to vent some of the compressed steam from the cushioning cylinders between the pistons 15 and 16 and the end plates into the spaces between the cushioning pistons and the piston valve 20 as relief or protection. To that ends the liner of each-of the cushioning cylinders and 6|. is provided with a plurality of ducts ||I|| adjacent the end plates 63 and 65 and extending a short distance therefrom and terminating short of the position which the at the end of the short valve travel, but extending sufiiciently far so that the end thereof will be uncovered at the end of the cushioning piston in long valve travel for permitting escape of compressed steam between the cushioning pisders at opposite sides of the over-all path of I travel of the respective cushioning pistons operating therein.

The respective by-passes and8| are provided therein with by- pass valves 83 and 84 respectively, the valve heads 85 of which are nor- A compressed air line 81 communicates with both of the by-pass valves and upon application of pressure the air piston is forced downward tons and their respective cushioning cylinder heads while locomotive is worked at long travel. The short valve travel of these cushioning pistons is well shown in Figures 2 and 3 of the drawings, and long valve travel of these cushioning pistons is shown in Figures 4 and 5 of drawings.

In order to compensate'for pressure differentials at the opposite sides of each of the cushioning pistons, their respective cylinder liners are also provided with vent ducts |0|- .at the inner ends of their movements, to permit of by-passing exhaust steam pressure under conditions of short and longvalve travel in a manner which will be mally maintained open by means of springs 86. I

and springs 86 will be compressed, as will be apparent from Figure 2 of the drawings, and close the valves 85 upon their seats in the casing of the respective by-pass valves in order to close off communication of each of the by-passlines 80 and 8|, so that there is no connection between the chamber portions of the inertia arrester cylinders at opposite-sides of the cushioning pistons respectively operating therein.

- The compressed air line 81 receives its air from a suitable tank 88, and a control valve 89 may be positionedin the line .81, under control of the engineer. This valve 89 has a valve head provided with three ways therein. Two of them may communicate opposite sides of the line 81,

thereby cushioning piston valve 20'.

apparent from the foregoing description.

In Figure 2 of the drawings where the parts are set for a short valve travel of the cushioning pistons, the forward cushioning piston 15 has reached its forward limit of movement and the steam between this piston 15 and the end plate 63 has been compressed several ratios above ex-I haust steam pressures in exhaust steam passages Also trapped compressed exhaust steam in cylinder 5| will assist in starting valve 20 in opposite direction, since the valve 85 is closed. The operation of the other cushioning piston 16 is exactly the reverse, as shown in Figures 2 and 3.

For a long valve travel of the cushioning pistons, as shown in Figure 4, the cushioning piston 15 operates against little or no steam pressure between-piston and the end plate 53, for no buffing is necessary at slow speeds,- with long travel.

Also, a short valve travel is.

Since at long travel and slow speeds the inertia is nil. Any steam compressed in this space by reason of long valve travel operation, if the valves 85 should not be open will be permitted to escape to the rear side of the piston 15,since the ports I will be uncovered as piston nears the extremity of forward movement of the piston 15, as shown in Figure 4. The piston 16 of course,

operates in a position opposite to the piston 15 with respect to the vent control ports I00 and IN. As shown in Figures 4 and 5, the by-pass valves are preferably open for long piston valve travel.

From the foregoing, it is apparent that it is in the last half of the piston valve travel, while the piston valve is operating at short travel, at high speeds that the cushioning is desirous and needed to arrest the inertia of the heavy piston valve, and the compressed exhauststeam that cushions the piston valve will assist in starting the piston valve in the reverse direction thereby relieving the valve gears of heavy pressure during the power thrusts that start the piston valve from standing position when the conventional type of piston valve is used; 1

The advantages resulting from the improved arrangement of impact cushioning means at each end of the piston valve chamber will be apparent to those who are familiar with locomotive piston valve operation. 1 Incident to gear reversing, the impact upon the reverse gearing is many times the force of the impact of the piston valve. When this force strikes the reversing motor, the reverse gearing has caught up with its work and is at rest, so that it receives the full force of the impact, before the piston, now moving, can actuate the necessary valves and parts to admit air to the air cylinder of the reverse gears. The air piston of the reversing gearing has moved against the air in the opposite end of the cylinder with such speed and power that the air is compressed, allowing point where -the machinery is placed in reverse motion while the locomotiveis running forward. This is a dangerous condition and is entirely eliminated with the improved inertia arresting means of this invention.

As a further means of pointing out the importance of the present invention, we may take a conventional locomotive having an eighty-four inch diameter driving wheel. It is not unusual for such a locomotive to run at speeds of 120 miles per hour. This means revolutions per second of the driver wheel. The .valves of the locomotive must admit steam to each end of the steam cylinder ofthe locomotive,

and exhaust steam from each end one time for each revolution of the drive wheel. This means four admissions and four exhausts for each revolution of the drive wheel and eight revolutions per second totals thirty-two admissions and thirty-two exhausts per second. The wear and tear upon the partsoccasioned by starting, stopping and reversing the piston valveunder such conditions is apparent, and the desirability of cushioning the force J sulting from the inertia arrester of the present invention is correspondingly apparent. In addition to the advantages above enumerated, the cushioning arrangement of the present invention provides for cushioning the piston valve; enabling the compressed steam that cush ions the piston valve to assist in the reversing direction after being stopped; prevents the reversing of the valve gears when the locomotive is the air reverse piston to continue to :the i that there are eight running at high speeds at short cut-oils; caused by inertia of heavy piston valves enables the engineer to operate the locomotive at the proper cut-off without danger of the valve gears being reversed; enables the piston valve to be maintained in a proper plane, thus eliminating frequent reboring operations of valve chamber bushings; eliminates excessive locomotive vibration at high speeds; improves riding quality of the locomotives, and does away with impacts delivered to cross-heads, thereby reducing maintenance cost.

Various changes in the shape, size and arrangement of parts may be made to the form of invention herein shown and described, without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. In a piston valve inertia arrester for'railway steam locomotive operating equipment, the

combination of a piston valve, a piston valve cyland the improvement reinder therefor, a cushioning piston connected with the piston valv a-cushioning piston cylinder within which the cushioning piston; operates, means for by-passing exhaust steam in the "ushioning cylinder from one side of the cushioning piston therein to the other side at each end of the stroke movement of the cushioning piston, and means for adjusting the cushioning pressure.

2. In a piston valve steam control assemblage for the operating-equipment of railway steam locomotives, the combination of a piston valve,

a piston valve' chambencushioning pistons secured rigidly with the piston valve in spaced relation at each end thereof, cushioning piston cylinders within which each of the cushioning pistonsoperates, by-passes .connected with each of the cushioning cylinders, each by-pass being connected for by-passing pressure from one side of the cushioning piston in the cushioning cylinder to the opposite side of that particular cushioning piston, control valves in each of said lay-passes, and means for opening or closing said valves to permitof lay-passing pressures when not needed. i

3. In a ,piston valve stea-mcontrol assemblage for the operating equipment of railway steam locomotives, the combination of a piston valve, a piston valve chamber, cushioning pistons secured rigidly with the piston valve in spaced relation at each end thereof, cushioning piston cylinders within which pistons operates, by-passes connected with each of the cushioning cylinders, each by-pass being connectedfor by-passing pressure from one side of the cushioning piston in the cushioning cylinder to the opposite side of that particular cushioning piston, control valves in each of said by-passes, andmeans for opening or closing said valves to permit of by-passing pressures when not needed and other means formed in the cushioning piston cylinders for by-passing cushioning pressure from one side of the cushioning ing steam control chamber in which the cushioning piston operates, a by-pass connected with the cushioning each of the cushioning ports, a cushioning piston connected with the piston valve, a cushioning piston piston chamber, for by-passiiig and admitting exhaust steam pressures from the cushioningend of the cushion'piston chamber when cushioning is not needed, and other by-pass ducts in the cushioning piston chamber disposed at the compression end of the cushioning piston chamber and adapted tobeuncovered for passing pressures from one sideof the cushioning piston to the other side thereof in said chamber as the cushioning piston approaches the extremities of its movement at long valve travel when cushioning is not needed.

5; In a piston valve inertia arrester for railway steam locomotive operating equipment, the combination ,of a piston valve, a piston valve cylinder therefor, a cushioning piston connected with the piston valve, a cushioning piston cylinaasns a 4 v I .der within which the c oiling piston operates,

means for by-passing res from one side of the cushioning piston to-the other side of the cushioning piston, within said cushioning pistoncylinder, and valve means for controlling said by-pass.

6. In a piston valve inertia arrester for railway steam locomotive operating equipment, the combination of a piston valve, a piston valve cylinder theretor, a cushioning piston connected with the piston valve, a cushioning piston cylinder within which the cushioning piston operates,

means for by-passing pressures from one side of the cushioning piston to the other side of the cushioning piston within said cushioning piston cylinder, valve means for controlling said bypass, and means cooperating with said valve means for entirely releasing pressure from said cushioning piston cylinder at each side of the cushioning piston valve.

CARLG; ASH.

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