US1943703A - Locomotive auxiliary port controlling mechanism - Google Patents

Description

4 Sheets-Sheet l H. J. TlTUS LOCOMOTIVE' AUXILIARY PORT CONTROLLING MECHANISM Filed Aug. 28, 1930 Jan. 16, 1934.

Jan. 16, 1934- H. J. Trrus 1,943,703

I LOCOMQTIVE AUXILIARY PORT CONTROLLING MECHANISM Filed Aug. 28, 1930 4 Sheets-Sheet 2 Q Al ww Jan. 16, 1934. H. J. TlTUS LOCOMOTIVE AUXILIARY PORT CONTROLLING MECHANISM Filed Aug. 28. 1930 4 Sheets-Sheet 3 A TTRNE Y5 a mm H. J. TITUS Jan. 16, 1934.

LOCOMOTIVE AUXILIARY PORT CONTROLLING MECHANISM Filed Aug. 28, 1930 4 Sheets-Sheet 4 l atentecl Jan. 16,

UNITED STATES Application August 28, 1930. Serial No. 478,534

15 Claims.

This invention relatesto a controlling mecha nism for the auxiliary or starting passages or ports of a limited cut-off locomotive.

One of the primary objects of the invention is to improve the operation and effectiveness of auxiliary or starting ports in a limited cut-ofi locomotive. I

Another important object of the invention involves increasing the efiiciency of a locomotive '10 having starting steam ports, particularly with respect to steam consumption.

I In addition, the invention has in view the elimination of certain difficulties which are encoun- IvII tered in the operation of the types or arrangement of starting ports at present in use.

More "specifically the invention provides for positively controlled opening of the starting ports between certain points in the cycle of operation II of each cylinder and for positively controlled closing of such ports at all points in the cycle at which admission of steam therethrough is unnecessary or undesirable The foregoing is not only advantageous in preventing wastage of steam In and the building up of undesirable pressure conditions at certain points in the cycle of operation, but also in permitting the use of relatively large and, consequently, more eiiective, auxiliary or starting ports. 7 Finally, the invention contemplates the provision of means, actuated'by movements of the locomotive reverse gear, for reversing the operation of the auxiliary port controlling mechanism such manner as to render such ports fully operative and effective either for forward or for 3'5 reverse operation of the locomotive.

How the foregoing objects and advantages together with others which will appear to those skilled in the art are obtained will be apparent I from a consideration of thefollowing description taken with the accompanying drawings in which I Fig. 1 is aside view of the forward portion of a locomotive to which the apparatus of the present invention has been applied, various of the locomotive parts being omitted for the sake of clarity in the drawings:

Fig. 2 includes portions of the cylinders and "associated valve mechanisms of a two cylinder limited cut-01f locomotive having starting ports, the two cylinders being arranged diagrammatically with respect to each other and being shown in vertical section, with certain of the auxiliary port controllingelements and connections diagraminatically indicated; II

Figs. 3,4 and 5 are views similar to Fig. '2 illustrating the pistons and valves at 'diiiere'nt points in the cycle of operation; I I

Fig. 6 is a diagrammatic layout of the various connections employed in the controlling meciia- N nism with portions of the cylinders and the asm sociated auxiliary port controlling valves shown in full lines and with the control reversing mechanism shown in elevation from one side and any; larger scale than the cylinders and controlling valves; I I I Fig. 7 is a sectional view of one of the controlling valves for the auxiliary ports; I I

Fig. 8 is an edge view of the reversingvalve or commutator, portions thereof being broken. away and shown in section on the line 8-8 of Fig. 6;

Fig. 9 is a fragmentary sectional view of the reversing valve taken on the line 9-9 of Fig. 6 illustrating certain passages therein not included in Fig. 8; and I I I I I Fig. 10 is a view similar to Fig. 6 showing the device in position for reverse operation. 1n this figure as in Fig. 6 the controlreversing mecha: nism is shown 'on a larger scale than the cylinders and controlling valves. I I

In the drawings, the controlling mechanism of the present invention is illustrated, by way of example, as applied to a two cylinder limited eutofi locomotive. I I I v I In Fig. 1 the boiler of the locomotivein indicated by the reference character 10 while driving wheels thereof are indicated at '11. The cylinders are indicated at 12 and 13 in Figs. i to 6 inclusive and the steam chests are designated by I the numerals 14 and 15. Pistons l6 and Hand 60 valves 18 and 19 are arranged to reciprocate within the cylinders 12 and 13 and th e valve chests 1e and 15, respectively, the valves here shown being of the inside admission type.

I Each cylinder and its associated valve chest provided with main steam supply passages'20 and 21 at the head and crank ends (indicated by the letters H and C) and with head and crank end auxiliary steam passages 22 and 23 arranged substantially in the usual relation with respect to the main steam supply passages. I I

Each one of the auxiliary steam supply Ipassages extends through and is controlled by 'a valve device 24 (diagrammatically indicated in Figs. 2 to 5 inclusive and shown in section in Fig.7). By reference to Fig. 7, it will be apparent that the valve 24 includes a body portion 25 housing a valve 26 which, in closed position (indicated in dot and dash lines), blocks off the passage 27 through which auxiliary steam is conducted by the passage or conduit 23, the direction of flow being as indicated by the arrows. The actuation of this valve to closed position is effected by means of some fluid pressure such, for example, as steam admitted through the passage 28 to the chamber 29 behind the piston-like portion 30 of the valve 26 which is adapted to work or reciprocate Within the chamber 29. On the other hand actuation of the valve 26 to open position is effected by admission of steam through the auxiliary passage 23 in the passage 27 from where the steam may enter the chamber or cavity 31 at the left-hand end of the valve 26 all as indicated in Fig. 7. The pressure on this end of the valve, of course, moves the valve to the right and opens the passage 27 and thus permits a flow of steam therethrough.

The fluid for closing the valves 24 is preferably supplied through pipes or conduits which communicate with ports in the steam chests of the cylinders. The manner in which these con nections are made will be apparent from a consideration of Figs. 2 to 5 inclusive and in considering these figures, it should be borne in mind that the connections diagrammatically indicated are those employed for forward running or operation of the locomotive, the following and leading cylinders in such forward operation being indicated by the reference letters F and L, respectively.

Referring now to Figs. 2 to 5 inclusive, each valve chest is provided with control ports 32 and 33 located adjacent the points of communication of the starting steam passages 22 and 23 and con- "trolled by the main valves 18 and 19. For forward operation of the locomotive the ports 32 and 33 of the leading cylinder are connected with the control valves 24 associated with the starting passages for the following cylinder, the connection being f om the head end port 32 to the head end valve 24 and from the crank end port 33 to the crank end valve 24. The ports 32 and 33 of the following cylinder are cormected, respectively, to the valves 24 at the crank and head ends of the leading cylinder.

The foregoing connections, must, of course, be reversed or inverted for rearward operation of the locomotive, it being noted that the cylinder 13 becomes the following instead of the leading cylinder while the cylinder 12 becomes the leading instead of the following cylinder during reverse operation. The mechanism employed for accomplishing the necessary inversion of the various connections can best be understood from a consideration of Figs. 6, 3 and 9. In these figures, a commutator or valve device V is illustrated, the same comprising stationary and movable elements 34 and 35, respectively. The reversing device V is illustrated in Fig. 6 as occupying the position necessary to make suitable connections for forward operation of the locomotive. These connections include suitable pipes or conduits which are interconnected through various passages in the valve V and may be followed out or traced to best advantage by reference to Fig. 5, bearing in mind the above description or" the diagrammatic connections applied to Figs. 2 to 5 inclusive. The valve device V shown in Figs. 6, 3 and 9 is omitted from Figs. 2-5 to avoid confusion. The port 32 at the head end of the chest 14 is coupled by means of the pipe 36 with the port 3'7 in the stationary portion 34 of the valve V, the latter communi ating, in turn, with the arcuate passage 38 in the valve member 35. With the valve in the position illustrated in this figure, the passage or cavity 38 also communicates with the port 39 in the valve member 34 which, in turn, is coupled with the passage of the control valve 24 at the crank end of the cylinder 13 by means of the conduit 40. The control port 33 at the crank end of the valve chest 14 is connected to the control valve 24 at the head end of cylinder 13 by means of connections similar to those just described, i. e., by means of conduit 41, port 42, cavity 43, port 44 and the connection 45.

The port 32 at the head end of valve chest 15 is coupled with the control valve 24 at the head end of cylinder 12 by the following connections: pipe 4", port 47, cavity 43, port 49 and pipe 50. The control port 33 at the crank end of valve chest 15 is coupled in a similar manner to valve 24 at the crank end of cylinder 12, i. e., through connections and passages 51, 52, 53, 54 and 55.

To effect the inversion of these connections necessary for reverse operation of the locomotive, the movable portion of the valve V is rotated in a clockwise direction (as viewed in Figure 6) by means of the link or shaft 56 which is connected to the lug 5'? of the valve member 35, the amount of movem: at being sufficient to bring the cavity 43 into registry with the ports 42 and 39. The position of the valve V for reverse operation is sh wn in Fig. 10.

The link 56 may be actuated by connection thereof to some suitable part of the locomotive reversing mechanism as illustrated in Fig. 1. This arrangement may include (see Fig. 1) a connection with the arm 58 through which the locomotive reverse gear reach rod 59 suitably actuates the valve gear. This connection is preferably effected by means of a pin 60 extended through an arcuate opening 61 in the crank or lever 58.

By reference, again, to Fig. 10 i will be seen that with the valve device V in reversed position, the auxiliary port controlling connections are reversed or inverted as follows:

Pipe 41 is coupled with the connection through. port 42, passage 43 and port 39. Conduits 36 and are coupled toge her by means of port 37, passage 38, port 44 and the cross passage 62 which is provided in the valve member 34 to connect the arcuate cavities 33 and 66, the latter registering with port 63 which communicates, in turn, with the port 44. The other connections are similarly altered, i. e., pipes and 51 are coupled together through port 49, cavity 53 port 52. The connection 46 now communicates with connection thru port 47, cross passage 64, port 65, arcuate passage 67 and port 54.

With the connections reversed it will be seen that the control port 32 at the head end of valve chest 14 is coupled with control valve 24 at the head end of the cylinder 13 while the control port 33 of the chest 14 is coupled with the other valve 24 of cylinder 13. On the other hand communication is established between the control port 32 at the head end of valve chest 15 and the control valve 24 at the crank end of cylinder 12, while the port 33 of valve chest 15 is put in communication with the control valve 24 at the head end of cylinder 12.

In considering the operation of the controlling a tive, the. c'ut -oi'f being at approximately 40 In Figure 2 the piston 161 of the following cylinder (for forward operation of the locomotive) is shown in mid-position moving to the left as indicated by the arrow. With this cylinder so bes'itioned, it will be, seen that the valve l'8 has already closed on themain port 20 so that if the cylinder 12 is to be effective in startingthe locomotive, steam must be admit through the auxiliary port or starting passage 22'; It will also be seen from inspection of this figureth'at the starting passage 22 is uncoveredand opened for admission of steam from the; chest. Steam may, therefore, enter the passage 22a'ndpa'ss therethrough intothe cylinder after it has opened the valve 24' associated therewith. The auxiliary steam is free to open thisvalve 24 at this particular point in the cycle of operation in view of the'fabt that the control passage for this valve communicates with the port 32 at the head end of the leading cylinder which, is closed off by the valve 19. In the absence of the admission of steam into the port 32, the steam entering the passage 22 is free to open the valve 24 and per-' mit a suitable flow into the cylinder 12 behind the piston. The admission through this port may continue up to the point of release through the main passage 20 at which time (see Fig. 3) the valve 18 covers the starting port and thus cuts off the auxiliary supply.

, With the piston position of Fig. 2 no steam may enter. the auxiliary passage 23 in view of the fact that the valve 18 covers the auxiliary port. In addition, it should be notedthat no steam may enter eithe'r cine of the, auxiliary passages of the leading cylinder. Admission to the passage' 22 is prevented by. virtue of the fact that the valve 19 has closed. the port associated therewith while admission of steam through the passage 231s prevented by virtue of the fact that the controlport 32 of the following cylinder is open for the admission of steam with the result thatthe valve 24 associated with the passage 23 v of the leading cylinder is positively retained in itslclosed position. a v 2 renewing thecycle now to the'point illustrated in Fig. 3, i. e., with the piston of the fellowing cylinder at the point of release it will be observed to begin with that admission of steam behind the piston in cylinder 12 is prevented by the valve 18. This, of course, prevents wastage of steam through the main port 20 upon release by the valve 18 for purposes of exhaust. Furtherat this point in the cycle of operation, with the main port 21 of the leading cylinder open or uncovered, admission of auxiliary steam is not necessary through any of the auxiliary or starting' passages. The valve 24 in the starting passage 23 of the following cylinder is positively closedby admission of steam through the port 33 of, the leading cylinder which is now uncovered. Thevalve's. 24 of the passages 22 and 23 of the leading cylinder are also positively closed by the admission of fluid pressure through the control ports 32 and 33 of the following cylinder.

In Fig. 4 the piston of the fdllowing cylinder is illustrated at the point of cut-off on the return stroke and, it will be noted that, at this point, the'valve 19 of the leadingrcylinder has closed the port 3350 that admission of steam tothe': auxiliary passage 23 of the following cylinder will open the valve associated thereand permit a' flow of steam into the cylinb n iid the; ist ni g I w l. i d. bifo nd, fioin iiisbctlo'fi'o'f Fig. 4, that aftfiispeifit the remaining three auxiliary passages are closed either by virtue of the position of the main valves or by virtue of theadmission of steam through the control passages. ,7

V In Fig. 5 the piston 16 of the following cylinder 12 is shown at the pointof release on the return stroke and it will be observed that, at this point, theauxiliary passage 23 of the following cylinder is just being closed by the valve 18 and that the action of both of the main valves and the control ports and passages prevents admission of steam through any of the other three starting passages.

From the foregoing consideration of Figs. 2 to 5 inclusive, it will be apparent that the auxil iary ports or passages are opened between the points of cut-off and release during each stroke in the cycle and that the starting or auxiliary ports are positively maintained closed during the remainder of each stroke. While the foregoing description deals more particularly with the following cylinder, it will be apparent that the same condition is produced inthe operation of the leading cylinder. Furthermore, the manner in which the controlling mechanism for the starting ports functions during reverse operation of the locomotive is quite obvious bearing in mind that for reverse operation the cylinders change from the leading to the following position with respect to each other.

The foregoing control mechanism is particularly advantageous because it permits the use of relatively large auxiliary or starting ports with the result that rapid and effective starting is provided. At the same time, even with relatively largev auxiliary passages, wastage of steam. is reduced to a minimum and undesirable increases of pressure at various points in the cycle are completely eliminated.

In addition to the foregoing, it might be noted that the controlling mechaniism of the present invention, particularly the auxiliary passage control valves, operate to eliminate substantially all admission of steam through the auxiliary passages after the locomotive has started and is running at speed. This condition is brought about by virtue of the fact that the points in the cycle between which the valves 24 would open at starting (between the points of cut-off and release) define only a small portion of each stroke in the cycle, while the portion of the cycle during lit which steam may enter the control ports 32 and.

33to effect a closing of the valves is relatively large or great in duration. Under these circum-- stances when the locomotive has gained a little speed, the time during which an effort is ex-,

erted toropen the valves 24 is too short to eifect or produce opening movement of the valves.

. lit;

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positive control of the starting ports to provide opening thereof between the pointsof cutoff and'release and closing thereof during the remainder of each stroke. Furthermore, the invention is characterized by the provision of start; ing port control mechanism the operation of."

which, is efiected at least in part by v interconj nection 'of thelcylinders'and valve mechanisms off the engine. This novel'type of control may; of

course, be modified Without departing from the spirit of the invention In general, therefore, it will be seen, that the invention contemplates the attainment of much more complete and flexible control of auxiliary or starting ports, by utilizing not only the valve mechanism of one cylinder to control the ports of that cylinder but also the valve mechanism of another cylinder in combination therewith.

I claim:

1. In a limited cut-off locomotive; the combination of a pair of cylinders; a valve chest associated with each cylinder having main ports and passages; a main distribution valve in each chest; a starting steam passage for each end of each cylinder; a fluid pressure operated control valve device in each passage; and a control mechanism for said valve devices including means for actuating the devices to open the passages between the points of cut-off and release of the' corresponding main ports and means for actuating the devices to close the passages between the points of release and cut-on of the corresponding main ports, the means last mentioned including a control port for each end of each chest and passages connecting said control ports and said control valve devices, the passages for the control ports in one chest being connected, respectively, with the control valve devices at the corresponding ends or" the opposite cylinder,

and the passages for the control ports in the other chest being connected, respectively, to the control valve devices at the opposite ends of the opposite cyinder.

2. In a limited cut-off locomotive; the combination of a pair of cylinders; a valve chest asso ciated with each cylinder having main ports and passages; a main distribution valve in each chest; means for reversing the operation of the main distribution valves to provide for reverse operation of the locomotive; a starting steam passage for each end of each cylinder; a fluid pressure operated control valve device in each passage; a control mechanism for said valve devices including means for actuating the devices to open the passages between the points of cut-off and release of the corresponding main ports, and means for actuating the devices to close the passages between the points or" release and cut ofi of the corresponding main parts, the means last mentioned including a control port for each end of each chest, and passages connecting said control ports and said control valve devices, the passages for the control ports in one chest being connected, respectively, with the control valve devices at the corresponding ends of the opposite cylinder, and the passages for the control ports in the other chest being connected, respectively, to the control valve devices at the opposite ends of the opposite cylinder; and means for reversing the connections between the control ports and said valve devices for reverse operation of the locomotive.

3. In a limited cut-on locomotive; the combination of a pair of cylinders; a valve chest associated with each cylinder having main ports and passages; a main distribution valve in each chest; means for reversing the operation of the main distribution valves to provide for reverse operation of the locomotive; a starting steam passage for each end of each cylinder; a fluid pressure operated control valve device in each passage; a control mechanism for said valve devices including means for actuating the devices to open the passages between the points of cut-ofif and release of the corresponding main ports, and means for actuating the devices to close the passages between the points of release and cut-off of the corresponding main ports, the means last mentioned including a control port for each end of each chest, and passages connecting said control ports and said control valve devices, the passages for the control ports in one chest being connected, respectively, with the control valve devices at the corresponding ends of the opposite cylinder, and the passages for the control ports in the other chest being connected, respectively, to the control valve devices at the opposite ends of the opposite cylinder; and means for reversing the connections between the control ports and said valve devices for reverse operation of the 10- comotive, the means last mentioned being connected with the means for reversing the main distribution valves to provide for joint reversal of both reversing means.

4:. In a limited cut-off fluid pressure operated engine, the combination of a cylinder, a pressure fluid chest for said cylinder, a main distribution valve in said chest, a starting passage communicating with said chest and said cylinder and being in part controlled by said main distribution valve, a second cylinder, a pressure-fluid chest for the second cylinder, a main distribution valve in the chest for the second cylinder, and means for controlling admission of fluid through said starting passage including a valve device with actuating means therefor operatively associated with the main distribution valve in the chest for the second cylinder.

5. In a limited cut-off locomotive, a cylinder, a steam chest associated with said cylinder and having main ports and passages, main distribution valve means for controlling said ports and passages; a second cylinder, a steam chest for the second cylinder having main ports and passsages, main distribution valve means for controlling the ports and passages of the chest for the second cylinder, an auxiliary or starting passage connecting the first cylinder and its associated chest and in part controlled by the main distribution valve means of the first cylinder, and control means for the auxiliary passage operated by the distribution valve means of the second cylinder.

6. In a limited cut-off locomotive, a cylinder, a steam chest associated with said cylinder and having main ports and passages, main distribution valve means for said main ports'and passages, a second cylinder, a steam chest associated with the second cylinder and having main ports and passages, main distribution valve means for,

atively coupled with the main distribution valve.

means for the second cylinder.

'7. In a limited cut-off locomotive, a cylinder, a steam chest associated with said cylinder and having main ports and passages, main distribution valve means for said main ports and passages, a second cylinder, a steam chest associated with the second cylinder and having main ports and passages, main distribution valve means for inder, the auxiliary passa'ge'being of later cut-off than a main steam port of said first cylinder, and controlmeans for said auxiliary passage including a valve,'a fluid pressure operated motor device associated therewith, and a passage connecting said motor device with the steam chest of the second cylinder and communicating therewith through a port subject to control by the distribution valve means of the said second cylinder.

'8. In a limited cut-off locomotive, a cylinder, a

steam chest associated with said cylinder and having m'ain ports and passages, main distribution valve means for said main ports and passages, a second cylinder, a steam chest associated connecting the first cylinder and its associated steam chest and being subject to controlby the main distribution valve means for the first cylinder, the auxiliary passage being of later cut-ofi' than a'main steam port of said first cylinder, and control means for said auxiliary passage including a valve, a fluid pressure operated motor device associated therewith, and a passage connecting said motor device with the steam chest of the second cylinder and communicating therewith through a port subject to control by the distribution valve means of the said second cylinder, the port last mentioned being of later cut-off than a main admission port of the second cylinder.

9. In a limited cut-oir locomotive, the combination of leading and following cylinders, steam chests associated with the cylinders and having main ports and passages, main distribution valve means associated with said chests for controlling said main ports and passages, a starting passage for each end of each cylinder, each starting passage being connected with the chest associated with the cylinder into which the passage dis charges and being of later cut-on than the main port at the corresponding end of the particular cylinder, a valve device in each starting passage, a fluid pressure operated motor device for closing each valve device, and a passage for each motor device extended therefrom and connected with the steam chest of another cylinder through a control port subject to control by the main distribution valve means in the chest of said other cylinder, the arrangement further being characterized by the location of the control ports for the motor devices of a leading cylinder toward opposite ends of the steam chest of a following cylinder and the location of the control ports for the motor devices of a following cylinder toward the corresponding ends of the steam chest of a leading cylinder.

10. In a limited cut-ofi locomotive, a cylinder, a steam chest associated with said cylinder having main ports and passages, main distribution valve means for said chest, a second cylinder, a steam chest associated with the second cylinder and having main ports and passages, main distribution valve means for the chest of the second cylinder, means for reversing the operation of operated valve device for said starting passage,

a pair of fluid pressure connections each having a port communicating with the steam chest of the second cylinder for control by the main distribution valve means therein, and means for selectively connecting said valve device for the starting passage with either one of said fluid pressure connections, whereby to provide for forward or reverse operation of the starting passage.

11. In a limited cut-off locomotive, a cylinder,

a steam chest associated with said cylinder having main ports and passages, main distribution valve means for said chest, a second cylinder, a steam chest associated with the second cylinder and having main ports and passages, main distribution valve means for the chest of the second cylinder, means for reversing the operation of the main distribution valve means to provide ,for reverse operation of the locomotive, a starting steam passage for one cylinder connected with its associated steam chest and being of later cutofi than a main port thereof, a fluid pressure operated valve device for said starting passage, a pair of fluid pressure connections each having a port communicating with the steam chest of the second cylinder for control by the main distribution valve means therein,.and means for selectively connecting said valve device for the starting passage with either one of said fluid pressure connections, whereby to provide for forward or reverse operation of the starting passage, said means for selectively connecting the starting passage valve device with either of said fluid pressure connections and said means for reversing the operation of the main distribution valve means being coupled together for related operation so as to provide for conjoint reversal of the main distribution valve means and the starting passage.

12. In a limited cut-off locomotive, a cylinder, a steam chest associated therewith having main ports and passages, a main distribution valve in said chest, a starting steam passage connecting said chest and said cylinder, a control valve in said starting steam passage with fluid pressure means for actuating it, a second cylinder, a steam chest associated with the second cylinder and having main ports and passages, a main distribution valve in the chest for the second cylinder, means for opening said control valve between the points of cut-ofl" and release of the first cylinder, and means for closing said control valve between the points of release and cut-oil of the first cylinder, the means last mentioned including a passage connecting the fluid pressure actuating means for said control valve with the steam chest for the second cylinder at a point to provide control of said passage by the main distribution valve in the chest of said second cylinder.

13. In a limited cut-oiT locomotive, a cylinder, a steam chest associated therewith having main ports and passages, a main distribution valve in said chest, a starting steam passage connecting said chest and said cylinder, a control valve in said starting steam passage with fluid pressure means for actuating it, a second cylinder, a steam chest associated with the second cylinder and having main ports and passages, a main distribution valve in the chest for the second cylinder, fluid pressure means operated by steam pressure in the starting steam passage for opening the control valve therein, and means for closing said control valve between the points of release and cut-ofl of the first cylinder, the means last mentioned including a passage connecting the fiuid pressure actuating means for said control valve with the steam chest for the second cylinder at a point to provide control of said passage by the main distribution valve in the chest of said second cylinder.

14. In a limited cut-01f locomotive; a cylinder; a valve chest associated with said cylinder and having main ports and passages; a main distribution valve in said chest; a starting steam passage for each end of said cylinder connected with the corresponding ends of said chest; a second cylinder; a valve chest associated with the second cylinder and having main ports and passages; a main distribution valve in the chest for the secand cylinder; a starting steam passage for each end of the second cylinder connected with the corresponding ends of the chest for the second cylinder; a fluid pressure operated control valve device in each starting passage; and a control mechanism for said valve devices including means for actuating the devices to open the passages between the points of cut-off and release of the corresponding main ports and means for actuating the devices to close the passages between the points of release and cut-off of the corresponding main ports, the means last mentioned including a control port for each end of each chest and passages connecting said control ports and said control valve devices, the passages for the control ports in the chest for the first cylinder being connected, respectively, with the control valve devices at the corresponding ends of the second cylinder, and the passages for the control ports in the chest for the second cylinder being connected, respectively, to the control valve devices at the opposite ends of the first cylinder.

15. In a limited cut-off locomotive, a cylinder, a steam chest associated with the cylinder and having main ports and passages, a main distribution valve in said chest, a starting steam passage for one end of said cylinder connected with said chest and being of later cut-off than the main port at the corresponding end of the chest, a second cylinder, a steam chest for the second cylinder, a main distribution valve in the chest for the second cylinder, a control valve in said starting steam passage, means for opening said valve between the points of cut-off and release of said main port, a fluid pressure device for closing said valve, and a passage connecting said device with the steam chest for the second cylinder at a point to provide control of said passage by the main distribution valve in the chest of said second cylinder.

HUBERT J. TITUS.

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