US1942369A - Auxiliary distributing valve for locomotives - Google Patents

Description

Jan. 2, 1934. H, TI DQUGHTY 1,942,369

AUXILIARY DISTRIBUTING VALVE FOR LOCOMOTIVES Filed Nov. 2, 1928 2 Sheets-Sheet l Il R n QQ LLI- hm N \m l* "W H-I--J-H TJ l N l l-'fw w N x 1 Gx ,I xg 1 Ml l Q Q y l LQ l\ $111-1: 1 51" N l y [H+-+44 wl @J *X Q Il i M nl Q o mon JanrZ, 1934. H. T. DouGHTY AUXILIARY DISTRIBUTING VALVE FOR LOCOMOTIVES 2 Sheets-Sheet 2 Filed Nov. 2, 1928 Patented Jan. 2, 1934 UNITED STATES AUXEBLIARY DISTRIBUTENG VALVE FOR LOCOMOTEVES 6 Claims.

This invention relates to a reciprocating steam engine and particularly to a novel valve structure for such an engine. As is well known, the steam is supplied to the steam chest or valve chamber in such an engine and it is distributed to the cylinder by the steam valve, which is usually of the reciprocating type. When a locomotive of the reciprocating steam engine type is pulling a train a great force is necessary when 10 the engine starts in order to start the train. In order to secure this force and particularly on account of the fact that the steam inlet on one cylinder or one side of the locomotive may be closed, it is necessary to have the valve set to give a long cut-off. As is also well known, the driving rod connections to the driving wheels are quartered, or one is set ninety (90) degrees ahead of the other to prevent the cylinders of the locomotive from stopping on a dead center.

When starting, therefore, the driving rod be at a disadvantageous angle,

Numerous tests have shown that a simple locomotive will operate with greatest eiiciency when running with the valve gear hooked up or with a cut-off of from twenty-five (25) to iifty (.50) 4percent of the stroke. lt is also known that a minimum cut-off of approximately eighty (80) percent of the piston stroke is necessary to satisfactorily start a capacity train at all times and with a two (2) cylinder locomotive cut-offs up to ninety (90) percent are used. The train resistance or necessary pull at starting decreases rapidly until a speed or three (3) to ve (5) miles an hour is reached, at which time it slightly increases as the speed is increased. The majority of locomotives are operated ineiiiciently because the long cut-oit which is necessary at starting is maintained long after the need for it is past. This is particularly true of switching locomotives due to the fact that they are constantly starting and stopping and the engineers are'too busy and do not have the proper equipment to check the cut-oit. When the long cut-off is thus used, the steam is not used expansively and is exhausted to the atmosphere at high temperatures and pressures. This exhaust steam represents a large amount of coal and water expended from which no return is had. It is evidentv that the ideal use of the steam would be one in which the expansive properties were efficiently used at all times and a locomotive so using the steam would start as quickly and haul at the same o-r faster speed the same tonnage handled by a similar locomotive using the inefcient long cut-off.

It is an object of this invention, therefore, 4to provide a valve mechanism which Will give the necessary long cutmoff for the steam when the engine is starting and moving at slow speeds, but which will decrease the cut-off as the speed oi the locomotive increases.

It is a further object of the invention to provide a locomotive having an auxiliary` steam valve in addition to the main valve, which auxiliary valve distributes steam to the cylinder and y is constructed and arranged to vary the cut-off at different speeds.

t is more specically an object of the invention to provide a valve mechanism for a locomotive comprising in addition to the main valve an auxiliary vaive for distributing steam to the cylinder, having sections fixed in relation to the valve rod and having a section movable in relation to the valve rod for varying the lap 0I" the valve and thus varying the cut-oil.

It is also an object of the invention to provide a valve mechanism for a locomotive which will automatically vary the cut-on 01 the steam distributed to the cylinders in accordance with the speed of the locomotive.

These and other objects and advantages of the invention will be fully set forth in the following description made in connection with the accompanying drawings in which like reference characters refer to the same parts throughout the different views, and in which,

Fig. 1 is a central vertical longitudinal section through the cylinder and valve members of a locomotive showing the invention. y

Fig. 2 is a view in end elevation of the parts shown in Fig. l, the same being shown on a smaller scale;

Fig. 3 is a vertical section through the auxiliary valve and bushings shown on an enlarged scale;

Fig. 4 is a view in side elevation of a cylinder 95 and valve chamber of a locomotive showing a modiiication; and f Fig. 5 is a view in end elevation of the parts shown in Fig. 4.

Fig. 6 is a vertical section similar to Fig. 4 showing the auxiliary valve just at the beginning of the cut-01T position when the same is moving at high speeds.

Fig. '7 is a view similar to Fig. 4 showing the auxiliary valve just about to cut oi with the parts `v105 in position `as when moving at slow speeds.

Referring to the drawings, the cylinder saddle l0 of a locomotive is shown to which is connected, as usual, the steam pipe l1. The saddle 10 is bored to form the steam cylinder 12 having fitted there- 110 in the bushing 13, in which moves the usual piston 14, equipped with the customary rings 15, which piston is secured to the piston rod 16. Said piston rod is shown as having a tapered portion extending through piston 15 with a shoulder forming collar 16a at one side of the piston, and a nut 1'7 threaded on the rod 16 at the other side of the piston. Steam is distributed to the ends of cylinder 12 through the ports or steam pase sages 18. These ports lead to the valve chamber 19 also formed in the cylinder saddle, which is provided with the bushings 20, which bushings have the ports or openings 29a therein connecting with the ports or passages 18. The valve chamber is closed at its ends by the heads 21. Steam is supplied to the valve chamber 19 at the central portion thereof between bushings 20, said steam being supplied by the pipe 11. A distributing valve 22 of the reciprocating` type moves in the bushings 20, having the steam and port controlling end portions 22a in which are tted the usual rings 23. Said valve 22 is connected to the reciprocating valve rod 24, extending through one of the heads 2l, which will be reciprocated in the usual manner by the valve gear of the locomotive. The steam from the cylinder 12 is exhausted alternately through the ports 13 and into the passages 19a, which connect with suitable exhaust ports in the cylinder saddle leading as usual to the exhaust nozzle.

In accordance with the present invention a valve casing 25 is provided which in the embodiment of the invention illustrated in Fig. 1 is disposed above the valve chamber 19. Casing 25 has the bushings 26 tted therein and connects at its central portion with the central portion of chamber 19 through the conduit 27. Casing 25 is closed at its end by the heads 23. The bushings 26 have the ports or openings 26a therein communicating with the annular ports or passages 25a, which are connected by conduits 29 to the passages 18 of steam chamber or casing 19. For a reason to be later explained, the conduits 29 connect the passages 25o. at one end of casing 25 to the passages 18, at the opposite end oi' chamber 19. The opposite ends of the chamber within casing 25 are connected by a by-pass conduit 30, which preferably is provided with a vent pipe 31 leading to the atmosphere. An auxiliary valve described generally as 32 is disposed in the bushings 26 and reciprocates therein, said valve being connected to a valve rod 33 passing through one of the heads 23, which head is shown as provided with a packing member 34 compreming the packing 35 about the rod 33. The outer end of rod 33 is pivotally connected to one end of a link 36, pivotally connected at its other end to the upper end of a lever 37, which lever is pivoted intermediate its ends at 38 to an upwardly and outwardly extending bracket 39 carried on one of the heads 21. The lower end of lever 37 is pivotally connected to one end of a link 40, pivotally connected at its other end to a bracket 41 secured tothe valve rod 24 in any suitable manner, as by the pin connection 42. From the described structure it will be seen that upon reciprocation of rod 24, rod 33 will be reciprocated but in a reverse direction to rod 24. Itis for this reason that the conduits 29 lead to opposite ends of casings 25 and 19. The valve 32 comprises a pair of end sections 43 secured to the tapered portions 33a of rod 33 by the nuts 44. These sections 43 are provided with valve rings 45 and reciprocate in the bushings 26 to control the passage of steam through the ports 26a. The inner ends of sections 43 are bored to receive reduced end portions 46a of a movable section 46, forming part of valve 32. Member 46 has larger portions 46h forming a shoulder with portions 46c, which portions 46h are equipped with the rings 47. Portions 46D are connected by hollow sleeve portion 46c surrounded and spaced from valve rod 33. Portions 46a are bored at their centers to receive reduced central portions 43a of members 43, said portions 43a being equipped with small rings 48 engaging portions 46a. Portions 46a also carry small rings 49 engaging the inner wall of the bores in members 43. Portions 465 are provided with relief ports or passages 46d extending from the opening in sleeve 46c to the space between members 43 and portions 46a adjacent the bushings 26. Members 43 are also provided with throttling ports or passages 43h extending from their outer ends to the inner bored portions thereof which receive portions 46a.

With the described structure it will be seen that when valve 22 is reciprocated the valve 32 will also be reciprocated in the opposite direction. With such a main valve as shown at 22, if we assume a two (2) cylinder simple locomotive with cylinders twenty-two (22) inches in diameter and thirty (30) inches long, driving wheels fty-ve (55) inches in diameter and steam pressure of one hundred and eighty (130) pounds with a maximum valve travel of seven 1.

(7) inches, one (1) inch steam lap and one-sixteenth (le) inch lead, the valve would have a maximum cut-or in full gear of slightly more than ninety percent and according to the usual formula, such a locomotive would develop a tractive force of about iorty thousand four hundred (40,490) pounds. If the same valve travel and lead were maintained but the steam lap increased to two (2) inches, the maximum cut-oit would be reduced to about sixty-six and four-tenths percent (6614-o 0). The boiler pressure could thus be Vraised to two hundred (200) pounds and if an auxiliary supply of steam to the cylinders were provided for starting purposes,

the locomotive would be computed to have tractive force of about forty thousand nine hundred (40,900) pounds. The main valve shown in Fig. 1 is designed to have a two (2) inch lap and thus to cut off at about sixty-six and four-tenths percent (66%%) of the stroke. Assuming this ngure, the distance indicated as Y in Fig. 3'would be three-fourth (SAL) of an inch, and the distance Z one-fourth (1/4) of an inch. It will be seen that the distance Y can be increasedv by a further movement of the central portion46c of valve 32 to the left as shown in Fig. 3 to one (1) inch. The lever 37 has its long arm twice the length of the short arm so that a ratio of movement oi two to one is given between valves 22 and 32. The valve 22 having a stteam lap of 5.

two (2) inches and a lead of one-sixteenth (14g) inch, with a rigid auxiliary valve `of the same type as the main valve, the auxiliary valve would have a lap of one (l) inch vand a lead of onethirtysecond (g1g) of an inch. Both valves, under such conditions, would have the same cutoff of about sixty-six and four-tenths percent (664o o) 22 is moving forwards or to the right, as shown in Fig. l, and has just closed the rear port 20a, the auxiliary valve at this time is moved back,- ward. When the valve rod 33 moves backward or to the left, in Fig. 1, the section 43 moves relatively to the section 46c at the right hand end of the valve and the opening Z is closed. This Assuming now that the main valve iso gives the auxiliary valve a steam lap of onehalf (1/2) inch or the amount required for a ninety percent (90%) cut-oi. In other words, the section 46c will not be moved until opening Z at the right is closed. This obviously will delay the movement and therefore the cut-01T made by the left hand end of section 46c. The lap at `the left hand end obviously has been reduced to one-half inch, and the cut-off will be delayed until substantially 90% of the stroke has been made. The Valve 32, therefore, will not cut off the steam at the port 26a at the end of the valve that makes the cut-off untilninetypercent (90%) of the stroke of piston 14 has taken place and the auxiliary valve will thus deliver steam to the cylinder after the main valve has closed the port 20a. It is obvious that the same action will take place at both ends of the cylinder and valve. With the structure described, therefore, when the engine is starting or moving at slow speeds, functions so that the main valve cuts ofi at about sixty-six and four-tenths percent (S-0%) of the stroke, while the auxiliary valve cuts off at a much greater percent of the stroke. A long cut off is thus obtained at starting or at slow speeds. In Fig. 7 the auxiliary valve is shown with the parts in the positions they occupy when the locomotive is moving at slow speeds and the valve is in position just beginning the cutting off in the casing 26 at the right of said ligure, said valve moving to the left as seen in said figure. After the locomotive has started and begins to pick up speed, the supply of steam by the auxiliary valve is cut down in three ways. Any one of these three ways operating alone would greatly reduce the steam supply by the auxiliary valve and the combination of all three will permit only a negligible amount of steam to be supplied by the auxiliary valve when the locomotive is moving at medium or high speeds. The iirst way that the steam supply is reduced is by the engineer hooking up his engine or valve as is customarily done. Hooking up the valve reduces the length of the valve travel and the valve travel of the auxiliary valve is reduced proportionately to that of the main valve. This causes a shorter cut off. The second way in which the steam .supplied by the auxiliary valve is reduced is by wire drawing of the steam through the comparatively small ports 26a. As the motion of valve 32 becomes rapid there is relatively small time for the steam togo through these ports and the well known wire drawing action takes place. The third way in which the supply of steam by the auxiliary valve is reduced is by the action of movable section 46 of valve 32. The ends 46a of section 46 form with the bores in members 43 dash pots which tend to retard the movement of section 46. The ports 43h, it will be seen, form regulating or throttling ports for these dash pots and are so proportioned that they allow the movement of section 46 to close the openings Z only at the slowest movements of the valve. The by-pass pipe 30 is also proportioned to get this result. It is evident, therefore, that as the speed increases, all of the air will not escape from the dash pots through the ports 43h, and the by-pass 30, and the openings Z, therefore, will not be entirely closed and the movable or floating section 46 will cushion on the air in the dash pots. At each reciprocation air flows into holes 43D as their outer ends move against the air and this presses on portion 46a. This action is the same at both ends and the section 46a is thus held central. Increasing the dimension of openings Z increases the steam lap of4 the valve v32 and this shortens the cut-off. It is obvious that with section 46c moving with section 43, so that there is no relative motion between the sections, that section 46c Will make the cut-oit sooner. In Fig. 6 the auxiliary valve is shown with the parts in the positions they occupy when the locomotive is moving at high speeds and the valve is in position just about to -cut oii the port 26a shown at the right in casing 26 the valve moving to the left. At medium or high speeds, therefore, the end sections 4S necessarily maintain their travel in direct relation to the main valve, while the floating valve section 46 will have practically no travel due to the action of the dash pots. The lap of valve 32 at the end making the cut-oil? is thus greater at the higher speeds and the cut-ofi is reduced. The section 46c will, at high speeds, be approximately central, so that there is about three-quarters of an inch lap at each end of the valve and the cutoff at each end thus takes place much sooner. The relief ports 46d are provided to allow parts 4Gb and 43 to come together at slow speeds. These ports permit any air trapped between section 46 and section 43 to be by-passed or relieved. The by-pass 3i) maintains an equal pressure at each end of the auxiliary valve and this by-pass preferably is vented to the atmosphere in order to keep the temperature and pressure at the ends of casing 25 near that of the atmosphere. This prevents any contact of hot steam and oil in the ends of casing 25, which might result in a deposit of carbon. It will be seen that pounding of the movable section 46 at high speeds is prevented by the air in the dash pots and, any pounding of this section at slow speed can be controlled by the ports 46d. The auxiliary valve 32 Will be lubricated by the oil carried over with the steam from the main steam `chest 19 but additional lubrication could, of course, be provided if necessary.

The auxiliary valve casing 25 of course, be placed in different positions. In Fig. 4 the same is shown as a casing 50 disposed below the main valve casing 19. The auxiliary valve rod 33 is pivctally connected to a lever 51 pivoted at its lower end to a bracket 52 projecting from the cylinder saddle and pivotally connected at its upper end to the main valve rod 24. The by-pass conduit 53 is shown connecting the ends of auxiliary valve casing 50, having a vent 54 to the atmosphere. With the construction shown in Fig. 4 both valve rods are moved simultaneously in the same direction so that reversal of the conduits or passages from casing 50 to the cylinder is unnecessary. The passages can open directly from the casing 50 into the cylinder 55. The structure shown in Figs. 4 and 5 could, of course,

be used where the device was applied to a new j.

locomotive and both casings could be cast directly in the cylinder saddle. The operation of the structure shown in Figs. 4 and 5 is, of course, the saine as already described in Figs. 1 and 3.

From the above description it is seen that applicant has provided a very simple and eicient valve structure for a locomotive or other reciprocating steam engine, which will automatically vary the lap of the valves and the cut-oi so that the engine will Work at an ecient cut-off at all times. g

As stated, the device is automatic and the engineer does not have to take time to regulate or adjust the valve mechanism. The device can be installed in new engines or locomotives and can be applied as an attachment to locomotives alisc CJD

ready in` use. The present structure can be applied to a locomotive at comparatively small cost and requires no further cost for maintenance. Its operation results'in a great saving or" fuel and the use of less Water, so that the cost of the device is saved many times over. It is apparent that the structure will have a high degree of utility for the purpose intended.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts Without departing from the scope of applicants invention, which, generally stated, consists in a device capable of carrying out the objects above set forth, such as shown and described and dened in the appended claims.

What is claimed is:

l. An auxiliary valvefor a steam engine having in combination with the main valve and main valve casing having ports leading to the steam engine cylinder, an auxiliary valve casing, an auxiliary valve movable in said casing, a valve rod for said auxiliary valve reciprocated in synchronism with said main valve, said auxiliary valve comprising end sections secured to and movable with said valve rod and a central section movable longitudinally relatively to said rod and end sections, said auxiliary valve having ports leading to said engine cylinder controlled by said auxiliary valve, the movement of said central movable section varying the action oi said auxiliary valve relatively to said ports and means permitting movement of said movable sections at slow speeds ci" said engine and retarding movement thereof at high speeds.

2. An auxiliary valve for 4a steam engine having in combination with a main valve and main valve casing having ports leading to the engine cylinder, an auxiliary valve casing, an auxiliary valve movable therein, means for moving said auxiliary valve in synchronism with said main valve, ports and passages extending from said auxiliary casing to said engine cylinder controlled by said auxiliary valve, said auxiliary valve having relatively longitudinally movable parts for varying the lap of said valve relatively to said last mentioned ports and for varying its point of cut oli as the speed of the engine increases, and means for cushioning said relatively movable parts in their movements.

3. An auxiliary valve for a steam engine having in combination with a main valve and main valve casing having ports leading to the engine cylindei', an auxiliary valve casing, an auxiliary valve movable therein, means for moving said auxiliar valve in synchronism with said main valve, ports leading from said auxiliary valve casing to said engine cylinder, said auxiliary valve comprising relatively longitudinally movable sections for controlling the eiiective length or said valve, said auxiliary valve having spaced portions co-operating respectively with said ports, means for supplying steam to said auxiliary casing between the end portions of said valve, one of said sections fitting in the other to orm a dash pot, and ports 'for said dash pot for controlling the action of said sections.

4. An auxiliary valve for a steam engine having in combination With the main valve and main valve casing having ports leading to the steam engine cylinder; a cylindrical auxiliary valve casing, a cylindrical auxiliary valve in said casing, a valve rod for said auxiliary valve reciprocating in synchronism with said main valve, said auxiliary valve having end sections fixed to said valve rod and engaging the Wall of said auxiliary casing and having a movable section movable longitudinally of said valve rod having spaced end portions engaging the Wall of said auxiliary casing and having telescoping relation respectively with said end sections to have relative longitudinal movement with said end sections in the reciprocation of said auxiliary valve in the operation of said engine to vary the lap oi said valve, said telescoping parts iorining dash pots to retard the relative movement of said end portions and said end sections at high speeds.

5. An auxiliary valve for a steam engine having in combination with the main valve and main valve casing having ports leading to the steam engine cylinder, a cylindrical auxiliary valve in said casing, a valve rod for said auxiliary valve reciprocating. in synchronism With said main valve, said auxiliary valve having end sections fixed to said valve rod and engaging the wall o said auxiliary casing and having a movable section movable longitudinally of said valve rod having spaced end portions engaging the Wall of said auxiliary casing and having telescoping relation respectively with said end sections to have relative longitudinal movement with said end sections in the reciprocation of said auxiliary valve in the operation of said engine to vary the lap of said valve, said telescoping parts forming an annular groove adjacent the Wall oi said auxiliary casing, said movable section having a bore forming a space around said valve rod and having ports in 'said end portions extending from said latter space to said rst mentioned space at the wall of said valve.

6. An auxiliary valve for a steam engine having in combination With the main valve and main valve casing, having ports leading to the steam engine cylinder, an auxiliary valve casing, an auxiliary valve movable in said casing, a valve rod for said auxiliary valve reciprocating in synchronism with said main valve, said auxiliary valve comprising end sections secured to and movabie 'with said valve rod and a central section movable longitudinally relatively to said rod and end sections, said auxiliary valve having ports leading to said engine cylinder controlled by said auxiliary valve, the movement of said central movable section varying the action of said auxiliary valve relatively to said ports, and

means carried by said auxiliary valve Within said 1 auxiliary casing for permitting iull relative inove-- ment of said end sections and central sections at slow speeds and retarding the relative movement thereof at high speeds.

I-ARTWELL T. DOUGHTY.

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