US402418A - Air-brake - Google Patents

Description

(No Model.) s sheetssheet 1. T. S. E. DIXON.

AIR BRAKE.

'Patented Apr. 30, 1889.

Ill/ll v voirs and their connections.

' ITED .STATES "PATENT FFIC.

TIAIERON S. E. DIXON, OF HYDE PARK, ILLINOIS.

AIR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 402,418, Vdated April 30, 1889.

Y Y Application filed February 18, 1889. Serial No. 300,253. (No model.) Y

To all whom) iv' 77u03/ concern.-

Beit known that I, THERON S. E. D1xoN,'a citizen ,of the United States of America, residing at Hyde Park, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Air-Brakes, of which the following is a speciiication.

Referring to the accompanying drawings, in which similar reference-letters indicate the same or corresponding parts, Figure 1 is an axial section of the valve-casing and its contained apparatus, taken in line x x of Fig. 2. Fig. 2 is a transverse section of the same, taken in line y y of Fig. 1. Fig. 3 is a partial section of the main and supplementary valves, taken in line z z of Fig. 2. Fig. 4 is a plan view of the main valve. Fig. 5 is a plan view of the supplementary valve. Fig. 6, is an axial section` illustrating the application of the principle withoutV the aid of a supplementary piston. Fig. 7 is a section in line y y of Fig. 1. Fig. 8 is a section showing a modification. Fig. 9 is a partialplan of the two main reser Fig. 10 is anarrangement of the same introducing certain improvements; and Fig. 11 is a cross-section of the waycock or engineers valve, showing a section of the ports and passages connected therewith.

In the following specification I shall use the term governing-valve device as meaning.

that device, whatever may be its construction, which is interposed between the air of the train-pipe and that of the auxiliary reservoir and operated by varying the pressure in the train-pipe to admit `air from the auxiliary reservoir to the brake-cylinder anddischarge it from the brake-cylinder to the atmosphere; the term local exhaust or local discharge as meaning a discharge of air under each car from the train-pipe to the brake-cylinder or the atmosphere (as the case maybe) by means of alocal vent provided for such purpose, and

` shall speak of the governing-valve device as moving outward or inward, according as it moves from or toward the auxiliaryreservoir and as beirg at the Yservice (or emergency) port when its main valve is in position to open said port, 'and it will be understood that I regard a flexible diaphragm or diaphragms as the known equivalent of a piston or pistons for the purpose of actuating the valves herex inafter mentioned. A

' This invention relates to the cla-ss of socalled automatic air-brakes, and,while con taining certain features useful in all brakes of that class, it is, in its main principles, an improvement upon the air-brakes patented to me May l, 1888, No. 382,032, and September 18, 1888, No. 389,643.

The paramount objects of my present invention are, iirst, to enable the engineer to grade the brake-pressure up and down at will while the brakes are set; second, to prevent shock between the cars in the application of the service-stop third, to enable the auxiliary reservoirs to be quickly refilled, and, fourth,

to eect with certaintya quick release of the embodiment in a variety of forms, so as to accomplish said obj ects independentlyby dif ferent structures or conjointly by oneand'the same structure. Among these novel features are, first, the employment of two exhaust ports or passages, through which air may be vented from the brake-cylinder to the atmosphere at different positions of the governing` valve device; secondly, making one of said exhaust ports or passages of large size, for a quick release of the brakes, and the other of small size, to slowly bleed off the air from the brake-cylinder in grading the brake-pressure down; thirdly, providing means for locally exhausting from the train-pipe in the act of moving the governing-valve device to open the service-port and closing such exhaust upon the open ing of the service-port; fourthly, providing means for locally exhausting from the train-pipe at two different positions of the governingvalve devicenamely, at one posiin the claims ap-y functions, and modes of operation capable of IOC tion for service-stop purposes and at another position for emergency-stop purposes iifthly, making said Alocal exhausts of different capacities, so as to amply exhaust in applying the emergency-stop, but only partially in applying the service-stop; sixthly, providing an ample passage for quickly refilling the auxiliary reservoir from the train-pipe controlled by a valve which normally holds such passage nearly closed, but opens the same upon an increase of pressure 1n the train-pipe for refilling the reservoirs, and, seventhly, providing a secondary main reservoir for use only in quickly releasing the brakes, or when the ordinary main reservoir is too much depleted for goed service.

The means for preventing shock at the service-stop, quickly refilling the auxiliary reservoirs, and grading the brake-pressure up and down at will .are so readily and easily embodied conjointly in one structure by a simple modification of the governing device described and shown in my patent of September 18, 1888, No. 389,643, that I shall herein treat that form as the preferable form of embodiment, and, for the purpose of facilitating comparison with said patent, I adopt in the accompanying drawings the same system of reference-letters so far as it may be applicable.

Thus D indicates the valve-casing; cl', the point at which the main train-pipe d is connected to said casing; F, the main piston; F, the supplementarypiston; E, the main valve; E', the supplementary valve; F3, the supplementary-piston stem; F4, the main-piston stem; F2, the interior chamber in the main piston; L, the spring-stem, and L the spring thereof, arranged in the outer part of the valve-casing; G, the passage leading from the interior of the valve-casing at the inner end of the governing-valve pistons to the brakecylinder; G', the brake-cylinder exhaust-port; g, the channel in the main valve, which at the proper time puts the passage G into communication with the port G to release the brakes; I-I, (shown in dotted lines,) the air-passage leading around said pistons from the trainpipe end to the auxiliary-reservoir end of the valve-casing; E2, the spring which presses the main valve against its seat; E3, the spring which presses the supplementary valve to its seat; e., the service -port 'or grading-port through the main valve; e', the emergencyport through the main valve; f, the packingring of the main piston; l, the valve controlled by the movement of the stem L for opening the local discharge; 2, the port covered and uncovered by the movement of the valve l; 3, the chamber into which said port leads; 4, the valve for controlling the discharge from chamber 3 to the atmosphere; 5, the port from chamber 3 to the atmosphere, and G the piston which closes valve l over port 5 when the air reaches the proper degree of pressure in the brake-cylinder.

The auxiliary reservoir is connected tothe valve-easing at the point marked (Z3, and this I term the inner end ofthe casing, and the opposite extremity the outer end. I employ a spring to perform the same function as the spring K of my former patent; but as it also performs important additional functions I have designated it as K to indicate at the same time its similitude and its difference. Bushings d2 are applied to the interior surfaces of the valve-casing where they are swept by the movements of the valves or pistons. As shown in Fig. l, the governingvalve device, consisting of the pistons F F and valves E E', with their accessories, is at the inner end of its traverse, with the passage G g G open and the brakes consequently released.

In my former patent the force of spring K was exerted against the supplementary valve in an inward direction only, thereby tending to move said valve back and close the service-port e of the main valve Whenever in the act of grading or making a service-stop the pressure in the auxiliary reservoir became reduced to or nearly to that remaining in the train-pipe. Inmy present invention, also, I use a spring force acting in the same direction upon the supplementary valve for the same purpose; but I also employ a spring force acting in the opposite direction upon said valve to perform other and very important functions.

For convenience, simplicity, and cheapness of construction I prefer to lodge both functions in one and the same spring, K and that is readily accomplished, for example, in the following manner: Attach to the inner end of the valve E (or to a spider connected therewith) a box or frame, k, having an opening through its inner end. Place a movable annular plate, k', within the box or frame, so as to rest upon the valve E, (or spider.) Reduce the diameter of the piston-stem F3. Pass the reduced portion through the plate k and attach to its inner end a plate, k2, and arrange the spring K between the plates 7a 7a2, as shown in Fig. 1. The spring should be so proportioned and adjusted as normally to hold the supplementary valve in an intermediate position between the inner and the outer limits of its traverse on the main valve, and, if a supplementary-valve piston is employed, to hold the latter in a like intermediate position between the limits of its independent traverse, as clearly indicated in Fig. l, and this intermediate position I term the normal position of the supplementary valve. By slightly increasing the air-pressure in the train-pipe the supplementary valve will be moved inward from its normal position against the resistance of the spring K', and, on the other hand, by slightly reducing lthe train-pipe pressure said valve will be moved outward from its normal position against the resistance of the same spring, in beth cases without necessarily moving the mai .n valve. This si mplc expedient-namely,

IOO

IIO

two valves.. oneof which, when` moved in either direction from its normal position with relation to-'the other, tends automatically to return to such normal positionenables me bythe mere arrangement of the air ports and passages to give my apparatus the ability to perform all three of the important functions of grading the brakefpressure up and down at will while the brakes are set, preventing shock in the application of the service-stop, and refilling the auxiliary reservoirs quickly Without danger of reflux in applying the Y brakes.

Ihe arrangement of the ports and passagfesfor grading the brake-pressure up andl down at will is as follows: `In one planeV or section line (see Figs. 2 and 3) a port, h, is cut through the main valve, a very small port, h', through the supplementary valve, and an elongated port, h2, through the main valve ini the -relative positions .substantially as shown. In another plane or section line (see Figs. l and 2) asmall port, g', is cut through the mainvalve into the exhaust-channel g thereof, and a passage, g2, is bored into the outer end'of the supplementary valve and plugged, having minute holes gs at its extremities in line with the ports e g of the main valve and at the `same distance apart. An open chanthe supplementary valve.

nel, likethe channel g, may be substituted for the passage g2; butI prefer the bored passage, because it produces less'frictionl on The supplementary valve may be made so ,short as to` uncover-the porte when moved outward and the port h when moved inward from' its nornow desires to apply his brakes for a servicestop, or to slacken the speed of thetrain, he vents the requisite quantity of air to bring the main piston F down upon the spring-stem L without displacing the latter. In this movement thel supplementary valve first moves outward from its norm al position, bring with the passage G and venting auxiliary.

reservoir air into the brake-cylinder. As

soon as the air-pressure becomes nearly equalized betweenthe auxiliary4 reservoir and train-pipe the spring K. returns the supplementary valve to its intermediateor, normal position with respect to the main valve, shut,-

ting off further access of air to the brake-cyl` inder and holding the pressure in the latter and allow the air to leak slowly from the brakecylinder tothe atmosphere. The same inward movement of the supplementary valve which thus brings the ports e g into communication also brings the ports and passages I rI h h2 into *communication with each other and allows air to pass slowly through them from the train-pipe side to the auxiliary-reservoir side of the controlling-piston, and thus again equalize the pressure upon it, whereupon the spring K returns the supplementary valve to its normal position and stops the es cape of air from the brake-cylinder. The engineer is thus enabled to grade his brake,- pressure up and down at will,while the brakes are set by merely venting fromv or into the train-pipe at the locomotive a small ,quantity of lair insufficient to disturb the main valve. In either vcase the operative port is opened at the will of the engineer, and almost immediately closed automatically, kby the equalization of pressure between the auxiliary res ervoir and train-pipe; but the engineer can hold it open' as long as he pleases by continuing slowly to vent the air at the locomotive from or to the train-pipe. Hence he can increase or decrease the brake-pressure to any degree that he may deem necessary under any conditions of service, and in reducing such pressure he is not obliged, as' heretofore, to waste the air already contained in the brakecylinder and draw upon the auxiliary reservoirs to supply its place. p

Another important advantage is secured by the same construction. ing-port has necessarily been made small, because, being wide open when the governingvalve device is at the inner end of its traverse, the reflux of air from the auxiliary reservoir would interfere with the movement of the gov,- erning-valve to set the brakes if the port were of large capacity. The smallerits capacity, however, the longer will it take to iill the reservoirs; but it is often very important to re- IOO IIO

Heretofore the rellill them quickly in order to get the necessary n moved inward from' its normal position will f uncover and open said port. When the govl erning-valve is at the inner end of its traverse, with the brakes released, the refilling-passage H h will therefore be but slightly' open, (j ust far enough to prevent ordinary leakage of the train-pipe from disturbing the valves;) but if the engineer increases the train-pipe pressure for the purpose of refilling his auxiliary reservoirs the supplementary valve immediately moves inward, openin g the rctillin gpassage wide open and rapidly charging the reservoirs, and then returns automatically to its normal position. The initial decrease of the train pipe pressure in the act of applying the brakes instantly closes the supplementary valve over the port 7L and entirely prevents redux of air from the reservoirs. It is obvious that the supplementary valve may be arranged to normally hold the port 7L entirely closed; but I prefervto leave it slightly open to counteract the eifects of train-pipe leakage, as above-indicated.

With the valves heretofore in use it has been necessary to suddenly vent four or five pounds of air from the train-pipe in order to insure the closing of the reiillingpassage preparatory to the movement of the main valve to set the brakes; but by my improvement this sudden initial venting is no longer necessary, because the ventingof a much smaller quantity of air will preliminarily eiteet with certainty the movement of the sensitive supplementary valve to close the refilling-passage.

The arrangement of the ports andpassages for preventing shockin the application of the service-stop is as follows: h3 is a transverse channel or bored passage in the supplementary valve, extending from section-line y y to section-line z e, (see Figs. 2, 4, and 5,) as shown in dotted lines in Fig. 5, and so arranged that when the main valve is at the inner end of its traverse and the supplementary valve is moved outward from its normal position one end of this passage or channel will communicate with the port g, (of the main valve,) leading to the exhaust G', while the other end will communicate with the refilling-port 7l, (of the main valve,) leading to the passage H, thus allowing air to slowly vent from the train-pipe to the atmosphere through the passages and ports H h h3 g g G.

The operation is as follows: The governing-valve device being in its normal position at the inner end of its traverse,with the brakes released, the engineer vents a small quantity of air from the train-pipe at the locomotive to apply the service stop. This moves the supplementary valve outward without disturbing the main valve, and thus opens the slow vent or leak from the train-pipe to the atmosphere through the ports and passages H h h3 g g G', as above described. The pressure now decreases in the train-pipe in consequence of the local discharge thus eitected until the superior pressure of the auxiliary reservoir moves the main valve outward, which movement instantly disconnects the port h from the passage H, and thus closes the local discharge, leaving the main valve at the serviceport. Air now vents from the auxiliary reservoir to the brakecylinder to set the brakes, and as soon as the pressure equalizes between the train-pipe and said reservoir the supplementary valve returns to its normal po sition, cutting oit communication from the reservoir to the lJrake-cylinder and 4holding the air-pressure in the latter. It will be observed that in order to initiate this operation it is only necessary for the engineer to open the way-cock for a moment, so as to allow a pound or two of air to vent from the train pipe to start the supplementary valve outward, whereupon he closes the way-cock and the governing-valves throughout the train take care of themselves, each in rapid succession opening the local vent until the main valve moves and then instantly closing it. Their action in this respect is not only auto matic, but wonderfully self -regulating, for each local discharge along the train adapts itself exactly to the degree of pressurereduction necessary to move its own main valve. Thus if in one car the main valve will move outward at a reduction of four pounds of pressure in the train-pipe the local discharge will reduce the pressure four pounds and no more at that valve. It in another car the main valve through a difference in its friction should stick slightly and require a reduction of eight pounds of pressure to move it, the local discharge at that point will reduce the pressure eight pounds and no more.V Hence the moving of each main valve is absolutely assured and the instant it moves the local discharge is closed, thus preventing all waste of train-pipe air. l-Ieretofore in applying the service-stop in long trains it has always required a considerable discharge of air (ordinarily at least eight pounds) at thc locomotive in order to operate the valves at the rear end of the train; but with my improvement the wave of pressure-reduction, initiated by a small and transient discharge at the l0- comotive and passing back through the train, is both accelerated and re-enforced at each local discharge, so that it reaches the rear end of thc train not only quicker than heretofore, but with undiminished power, assuring the prompt and effective operation of every governing-valve throughout the train. In no case, however, will the emergency-stop be accidentally applied, because the arrival of the main valve at the-service-port instantly .closes the local discharge and arrests the out ward movement of the governing-valve device at that point. It will be observed that the main valves are all moved directly by the local discharge in their vicinity. Hence by making the local discharge passage quite small, so as to act comparatively slowly, a considerable number of consecutive cars will be always locally discharging at the same moment, and as a result their main valves will move almost simultaneously, thus preventing IIO shock between the cars in the application of the service-stop. When the service-port has oncebeen opened, the engineer can keep it open aslong as he pleases by continuing a very slow vent of air at the locomotive, and thus increase his brake-pressure to any degree required, taking care not to vent fast enough or long enough to apply the einergency-stop, or by venting a little air into his train-pipe from the main reservoir he can move the supplementary valve inward beyond its normal position and open the leak from the'brake-cylinder to the atmosphere, thus reducing his brake-pressure to any degree required; as already hereinabove explained. The two movements of the supplementary valve-onc outward and the other inward from its normal position in respect to the main valve-thus enable him to apply his service-stop with a minimum expenditure of air and with absolute certainty and to grade his brake-pressure up and down at will without the damaging shock heretofore experienced between the cars upon the application of such stop.

In arranging the several-valve-ports I prefer to so adjust the port 7i with relationto the port h2 that when the main valve is atthe service-port and the supplementary valveis at its intermediate Vor normal positionl the communication between the ports h h2 will be nearly but not quite closed, so as to. leave a small leak through them to prevent any disturbance of the valves by the ordinary leakage from'the train-pipe; but they maybe adjusted to hold the passage closed at such 4 time if the constructeil shall prefer to do so.

My invention thus comprises, as an independent improvement, two exhaust-passages from the brake-cylinder to the atmosphereone an ample passage for releasing the brakes quickly and the other a restricted passage for slowly reducing their pressure without necessarily releasing thein-both of said passages being opened at the will of the engineer independently of eachother by increasing more or lessthe air-pressure in his train-pipe. It also comprises, as another independent improvement, an exhaust-passage from the trainpipe to the atmosph ere, opened by a reduction of train-pipe pressure preliminarily to the application of the service-stop and closed by the movement of the governing-valve device to apply such stop; and it comprises, as a third independent improvement, the employment of an ainpleArefllling-passage controlled by a valve which normally holds said passage nearly closed, but opens the saine upon an increase of pressure in the train-pipe for reiilling the auxiliary reservoirs. vThese new principles are capable of easy application without the aid of a supplementary piston-for example, las shown in Fig. 6. Here both valves are moved by the stem F4 of the main piston F .in such manner as to allow a limited degree of lost motion to the main valve, but not to the supplementary valve. The box or frame 7c is coniiectedto the main valve in any suitable manner-for example, by means of an' arm, 7c3, provided with a pin which works in a transverse open slot in the valve. rllie spider (shown at 7a4) is preferably arranged at the top of the box or frame and fastened thereto. Shoulders 't' t" are provided upon the stein Fl-the former to strike tlie outer eiid and the latter to strike the inner end of the main valve as the piston moves inward and outward. By the difference in the pressure of the springs E2 E3, or in any other available manner, the friction of themaiii valve against its seat is made considerably greater than that of the supplementary valve upon its seat, so that the latter m ayinove freely and easily without moving the former. Both in the structure of Fig. 6 and in that of Fig. l the force of the spring K is so adjusted that when under compression it will be able to move the supplementary valve Without necessarily moving the main valve. The ports are preferably arranged as already described. If preferred,

however, the ordinary Westinghouse leak or refilling-port I may be employed for reiilling the auxiliary reservoirs when the main valve is at the end of its traverse and for preventing the ordinary leakage of the trainpipe from disturbing .the valves, and a small supplement-ary leak or by-pass, I may be cut vinto the wall of the casing in such position to "perform the same functions when the main valve is at the service-port, being so arranged `as to be closed when the supplementary valve is drawn outward, nearly closed when said valve is at its intermediate or normal position,`and open when said valve is forced inward, but`always closedwhen the main valve local discharge under each car. The V'main valve then moves to the service-port and closes the local discharge. Equalization then closes the service-port, and thereafter the brake-pressure may be graded up and down at the will of the engineer, precisely as al ready described.

The structure shown in Fig. 6 has the merit of greater simplicity Jthan that'shown in Fig. I but I prefer the latter because it makes the friction kof the main valve and its controllingpiston entirely independent of Athat of the supplementary valve and its controlling-piston, and thereby enables ine to obtain nonsensitiveness where it is desirable inthe one valve and -great sensitiveness where it is equally desirable in vthe other, whereas iii the form shown in Fig. 6 the unavoidable friction of the packing-ring f detracts somewhat from the relative sensitiveness of. the supplementary valve. In either case the reroo IIO

lthe train-pipe at the locomotive movestlie 'supplementary valve outward and opens the quired non-sensitiveness of the main valve enables me to considerably enlarge its exhaust-channel g, and thereby secure an ample exhaust for the purpose of a very quick release of the brakes when necessary.

I retain in this application no claim upon the specific feature of the by-pass I', the same being divided out of this application to form the subject-mattei' of a separat-e divisional application.

In the forms hereinabove described the local exhaust from the train-pipe in applying the service-stop is effected by the movement of one valve and closed by the movement f another. Diiferent outlet-passages are provided in the casing D for the local exhausts in applying the service-stop and emergencystop, and the valve which controls the local exhaust at the service-port is arranged at the inner end of the governing-valve device and adapted to discharge train-pipe air to the atmosphere instead of discharging it into the brake-cylinder. These things, however, are all immaterial to the principle involved in this part of my invention, which may be readily applied in other ways-for example, as shown in Fig. 8.

To save duplicating drawings unnecessarily, I here represent only the parts which act at the outer end of the governing-valve device; but I place the drawing in such relation to Fig. '7 that the action of the entire structure will be readily understood. IIere, as before, a spring-stem, L, (now made in tubular form,) with its strong spring L', is employed to arrest the outward movement of the governing-valve device at the servicestop and to control the valve l, which opens a local exhaust through passage 2, in the application of the emergency-stop. In addition to this stem, however, I employ a supplementary stem, L2, movable outward against the resistance of a light spring, L3, and carrying between arms Z Z. a valve, Z2. Ports -7 r are cut through valves l Z2. lVhen the governing-valve device is at the service-stop, the arm l rests against the spring-stem L. W'hen at the inner end of its traverse, the arm may rest against stops Z3; or, if preferred, the stops may be omitted and the stem L2 made integral with the governing-valve piston or piston-stem.

Upon a slight reduction of train-pipe pressure the governing-valve device, moving outward, carries port r to port r and establishes a slow local exhaust through said ports, which brings the governing-valve device to the service-port and closes the local exhaust. The venting of a large amount of air from the train-pipe at the locomotive for the application of an emergency-stop causes the governing-valve device to carry both valves l Z2 outward beyond the passage 2, and thus open an ample local exhaust.

Here the local exhaust for service-stop purposes is both opened and closed by one and the same valve, acting in connection with a single exhaust-passage, with the same effect and upon the same general principle as when the main valveE and supplementary valve. E are employed for such purpose, as hereinabove described. Indeed, the single valve l2 could readily perform both functions Without the aid of valve 1 were it not for the fact that the air-pressure over the large exhaustport 2 would detract unduly from its sensitiveness.

Coming now to the fourth important feature of my invention, in order to effect a quick release of the brakes it is in all automatic air-brakes necessary for the engineer to suddenly and strongly increase the airpressure in his train-pipe, so as to insure the prompt movement of all the governing-valves to the inner end of their traverse. When, however, the auxiliary reservoirs contain a strong air-pressure and the main reservoir O has become depleted, it has always been necessary to resort to the air-pump O2 to increase the air-pressure in the main reservoir and train-pipe sufeiently to move the governingvalve device inward to the end of its traverse, and this operation takes considerable time and renders a quick release impossible. I now provide, as shown in Fig. 9, a secondary main reservoir, O', filled from the air-pump through the primary main reservoir O, or otherwise, and connected to the train-pipe by a separate passage, o, controlled by a cock. The primary main reservoir O is also connected, as heretofore, to the train-pipe by a passage, o', controlled by' the way-cock and provided with a reducing-valve, o2. A checkvalve, o3, should be interposed between the secondary main reservoir O and the source of its air-supply to prevent equalization from the secondary to the primary main reservoir when the latter is open to the train-pipe. The two main reservoirs will be preliminarily filled to the same degree of pressure; but the provision of two separate outlet-passages independently controlled enables the engineer to vent the contents of either at will into the train-pipe. In venting from the primary reservoir O into the train-pipe the checkvalve o3 prevents any air from being drawn from the secondary reservoir, and the reducing-valve o2 limits the attainable pressure in the train-pipe.

The primary reservoir O is to be employed for ordinary service purposes, as usual, the secondary reservoir O being reserved, with its maximum pressure undiminished, for use in quickly releasing the brakes and as a substitute for the primary or service reservoir O when the contents of the latter become at any time too greatly depleted. By this arrangement the engineer is provided, under all circumstances, with an ample air-supply for any purpose required, and can never be caught without the means rea-dy at hand for an almost instantaneous release of his brakes. Separate cocks may be provided for controlling the passages o o; hut I prefer to control both of them by a single way-cock havin g ports IOO IIO

which successively open said passages to the train-pipe at diferentpositions of the controlling-cock. Asa simple means for accomplishing this, I have shown in Fig. l1 a way-cock, P,

provided with a through-port, p, and valvesurfaces 19'192, as shown, and arranged with relation to the train-pipe cl, open air-vent Q, and passages o o as indicated, whereby all communication may be cut off, as represented in the drawings, or by turning the cock to succesv sive positions the reservoirs may be succesreadily place his way-cock in such a positionthat the air will vent through it in a thin stream, and therefore as slowly as he may desire, for service-stop or grading purposes.

Certainadvantages may be gained by substituting for the arrangement shown in Fig. -9 the arrangement represented in Fig. 10. Here the pipe 04, which leads from the airpump 02, runs both to the primary reservoir O and the secondary reservoir O', a controlling-cock, 05, being inserted in it between the pump and the secondary reservoir, and a reducing-valve, 06, between the pump and the primary reservoir. The two reservoirs are connected, as before, by a pipe, 07, provided with a check-valve, o3, and the passages o o and reducing-valve o2 in the latter are all retained.` With the reducing-valves set at twenty pounds, the engineer can provide an instantly-available force of, say, one hundred pounds in reservoir O for quickly releasing the brakes, while using normally only a maximum of sixty pounds in his train-pipe. In drawing air from reservoir O to the trainpipe the check-valve o3 will prevent any depletion of the secondary reservoir; but in drawing from the latter to the train-pipe the check-valve will open and feed from both reservoirs after equalization. The cock o5 is opened to ll thesecondary reservoir and l then closed to retain its pressure.

Turning now to other features of invention, in my patents of May l, 1888, No. 382,032, and September l8, 1888, No. 389,643, I described means for opening a local discharge from the train-pipe to the atmosphere in applying the emergency-stop, and also of closing the same by the action 'of the increasing air-pressure in vthe brake-cylinder -upon a piston or 'diaphragm thatcontrolled the valve of the outlet-port, illustrating in both of said patents an air chamber or space behind said piston and in communication with the passage by which air is vented from the auxiliary reservoir to the brake-cylinder in the act of setting the brakes. With this local discharge from the train-pipe it is desirable to hold the out` let-port open until a considerable air-pressure is attained in Vthe brake-cylinder and `then to close'it positively and hold it closed; hence it is desirable to hold down the air-pressure in the space behind said Vpiston to as low a de-` from the auxiliary reservoir through the passage G to the brake-cylinder will. tend, like an injector, to draw air from the space J and force it into the brake-cylinder till the pressure in the latter becomes nearly equal to that of the reservoir, after which the decreasing force of the air rushing through the passage G will allow the air-pressure to pass back through the passage J to the space J and close the outlet-valve. This object will measurably be accomplished by extending the passage .I into the side of the passage G atright angles with theV latter or in a direction in- 'clined toward the brake-cylinder; but for the best results I prefer to apply a bent nozzle, j, to the end ofthe passage J, so that it will project into the passage G and incline toward the brake-cylinder, and to slightly reduce the diameter of the passage G at the end of said nozzle by means of a bushing, j', as shown in Fig. l.- This arrangement is completely effective to hold the outlet-valve open as long as is desirable and then to close it and hold it closed. .Y

At times water is liable to collect in the 'lower recesses of the valve-casing D, and a cock or plug has heretofore been applied for the purpose of enabling it to be occasionally IOO drawn off. By extending a Vtube or passage,

M, from the lower portion of such recesses to the passage d, which leads from the train-pipe into the valve-casing, and providing it with a nozzle, m, similar to that shown at j', the rush of air from the train-pipe to the local-discharge port in the act of applying the emergencyvstop will draw up said water and force it through the outlet-port to the atmosphere,

thus dispensing with the aid of a separate plug for such purpose. Y In effecting the local discharge during the `application of the emergency-stop it is de- I sirable that no 'obstruction be oifered to the passage of the air through the valve-casing while on its way from the train-pipe to the outlet-port. Heretofore the stemL and mechanism connected therewith stood directly in IIO IIS

the path of such air-current and tended more or less to divide and obstruct the iiow thereof. I n'ow enlarge the stem L at this point,

so that it fills upV the space between the walls of the casing, and cut a port or passage, N, through it in such position that when the main valve E is at the emergency-port and the port 2 uncovered by the valve l the port or passage N will extend straight across from the end of the train-.pipe d to the open port 2, thereby affording a perfectly unobstructed pat-h for the escape of the train-pipe air. The end of the port or passage N nextto the train-pipe should be expanded or enlarged, so as always to be in communication therewith, and an opening, n, should be made from said port or passage N to the air-space` at the outer end oi the piston F, in order that the air-communication from the trailipipe to the governing-valve piston or pistons may always be open. In Fig. l a rubber dust-shield, s, of tubular form at its inner end and at at its outer end, is represented as applied to the outer end of the outlet-port 5 to prevent access of dust to the face of valves 4 and l. The spring force ot' the rubber holds its flattened end normally closed, but allows it to open under the force of air issuing from said outlet-port.

, Itis obvious that the refilling-passage Il, instead of being made entirely within the wall of the casing D, may be arranged in the form of a pipe extending outside of said casing and communicating therewith at the proper poin ts.

Having thus described my invention, what l claim as new, and desire to secure by Letters Patent, is

1. In a Huid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, and brake-cylinder with two exhaust ports or passages from the brake-cylinder to the atmosphere controlled by a governingvalve device provided with means for opening and closing either of said ports or passages at different times, at the will of the engineer, by varying the air-pressure in the train-pipe, substantially as described.

2. In a fluid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, and brake-cylinder with two exhaust ports or passages of different size from the brake-cylinder to the atmosphere, controlled by a governing-valve device provided with means for opening and closing either of said ports or passages at different times, at the will of the engineer, by varying the air-pressure in the train-pipe, substantially as described.

3. In a duid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, and brake-cylinder with an exhaust port or passage from the brake-cylinder to the atmosphere and a governing-valve device, so provided with ports as to adapt it to open said port or passage upon an increase of trainpipe air-pressure and to close it automatically by the equalization of pressure between the train-pipe and the auxiliary reservoir, substantially as described.

4. In a Huid-pressure brake mechanism, the combination of the train-pipe, brake-cylinder, and auxiliary reservoir with both a main and a second or supplelnental exhaust port or passage from the brake-cylinder to the atmosphere, the latter of which is controlled by a valve which is operated by varying the pressure in the train-pipe and which is opened against an opposing spring force, substantially as described.

5. In a fluid-pressure brake mechanism, the combination of a train-pipe, auxiliary reservoir, and brake-cylinder with two exhaust ports or passages from the brake-cylinder to the atmosphere and two valves of different s ensitiveness operated by varying the pressure in the train-pipe to control the discharge of air from the brake-cylinder to the atmosphere through said ports or passages, substantially as described.

b'. In a fluid-pressure brake mechanism, the combination of a train-pipe, auxiliary reservoir, and brake-cylinder with two exhaust ports or passages of different size from the brake-cylinder to the atmosphere, and amain valve whicl1,while holding the service-port open, holds the larger of said ports lor passages closed, and a supplementary valve which, while the main valve holds the'service-port open, is capable, by an independent movement, of opening and closing the smaller of said ports or passages, substantially as described.

7. In a duid-pressure brake mechanism, the combination ot' the train-pipe, auxiliary reservoir, and brake cylinder with two exhaust ports or passages of different size from the brake-cylinder to t-he atmosphere, a non-sensitive valve operated by varying the pressure in the train-pipe to govern the larger of said ports or passages, and a sensitive valve operated by varying the pressure in the trainpipe to govern the smaller of said ports or passages, substantially as described.

S. In a fluid-pressure brake mechanism, the combination of a train-pipe, auxiliary reservoir, and brake-cylinder with two exhaust ports or passages from the brake-cylinder to the atmosphere and a governing-valve device operated by varying the pressure in the train-pipe and adapted to open said ports 0r passages separately at different positions in its movement, substantially as described.

9. In a fluid-pressure brake mechanism, the combination of a train-pipe, auxiliary reservoir, and brake-cylinder with an ample exhaust port or passage from the brake-cylinder to the atmosphere for quickly releasing the brakes, a valve operated byvarying the pressure in the train-pipe and adapted to open said port or passage upon arrival at the inner end of its traverse, arestricted exhaust port or passage from the brake-cylinder to the atmosphere for slowly grading down' the brake-pressure, and a valve operated by varying the pressure in the train-pipe adapted to open and close said restricted port or passage, at the will of the engineer, when the governingvalve device is at the service-port, substantially as described.

10. In a duid-pressure brake mechanism, the combination of a train-pipe, auxiliary reservoir, and. brake-cylinder with a governingvalve device having a main valve and supplementary valve operated by varying the pressure in the train-pipe, and with an exhaust port or passage from the brake-cylinder to the atmosphere and an equalizing port or passage from the train-pipe to the auxiliary reservoir, said governing-Valve device being adapted to open both of said ports or pas- IOO IIO

sages when the main valve is at the serviceport and the supplementary valvehas be'en moved inwardindependently of the main valve, substantially as described.

1,1. In a duid-pressure brake mechanism, the combination of a train-pipe and auxiliary reservoir with a governing-valve device having a main valve and supplementary valveo'perated byvarying the pressure Ain the ,trainpipe,an equalizingport or passage from the trainpipe to the auxiliary reservoir, arranged and adapted to Vbe open when the main valve is .at the service-port and the Vsupplementary valve is moved inward to the extent of its limited independent movement, and aspring acting outwardly to close o`r nearly close said port or passage when the pressure has substantially equalized between the train-pipe and the auxiliary reservoir, substantially as described. Y

, 12. In aluid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, and brake-cylinder with an ample exhaustport ,or passage from the brake-cylinder to the atmosphere, a refilling port or passage from the train-pipe to the auxiliary re'servoir, and a valve device which opens said ports or passages when the governing-valve is at the inner extremity of its traverse, and

with a restricted exhaust port or passage from `th e brake-cylinder to the atmosphere, an equalizing port or passage from the train-pipe to the auxiliary reservoir, and a valve device which opens and closes said last-named ports or passages when the governing-valve is at the service-port, substantiallyV as described. y 13. In a fluid-pressure brake mechanism, the combination ofthe train-pipe, auxiliary reservoir, and brake-cylinder with a port or passage for locallyexhausting from thetrainpipe, and with a governing valve device adapted to open said port or passage upon a preliminary reduction of train-pipey pressure and close it by the movement of the governing-valve device to open the service-port, substantially as described. p

1-1. ln a huid-pressure brake mechanism,

. the combinationofthe train-pipe, auxiliary reservoir, brakefcylinder, and governingvalve device with a `port or passage for locally exhausting ,from the train-pipe, which is opened by the movement of a supplementary valve upon a preliminaryreduction of train-pipe pressure and closed by the movement of the governing-valve device to open the service-port, substantially as described.

15. ln a fluid-pressurebrake mechanism,

V the combination of the train-pipe and auxil- -tially as described.

-iary reservoir with a valved port or passage for locally exhausting from the train-pipe and a piston and valve operated by the' reduction of train-pipe pressure thus produced to close the local exhaust, substantially' as de-` scribed.

'1'7. In a fluid-pressurebrake mechanism,

vthecombination of the train-pipe and auxiliary reservoir, with two ports or passages of `dilferent size for locally exhausting fromthe trainpipe and a4 governing valve device adapted toppensaid portsV or passagesat'different positions in its "movement, substan- 18; ln a fluid-pressure brake mechanism, the combination of a train-pipe'and auxiliary reservoir with a main valve controlled by varying the pressure in the'train-pipe and a supplementary valve having a play in both directions from its `normal position with respect to the main valve, substantially as described. 4

19. In a duid-pressure brake mechanism, the combination of the train-pipe and auxiliary reservoirY with two valves, one of which has with relation to the vother ,a normal position, from'which it can be moved in two directions and tends to return automatieallyto such normal position when relieved from the moving force', substantially as described.

20. ln a fluid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, and mainvalve with a supplementary valve held in normal position with relationto the main valve by the action of opposite spring forces and 'capable of being moved in both directions from said normal viary reservoir with a port or passage for refilling said reservoir from said pipe, anda piston or valve which normally holds'said port or passage restrictedto the dimensions 'of a small equalizing port or passage, b ut opens the same wide open when the train-pipe pressure is increased 'for the purpose of refilling said reservoir, substantially as described.

23. In a huid-pressure brake mechanism, the combination of the train-pipe and auxiliary reservoir with a port or passagefor refilling said reservoir from said pipe, apiston or valve for controlling said port or passage, and a spring acting outwardly againstsaid piston or valve, and thereby causing it to hold said port or passage normallyrestricted to the dimensionsof a small equalizing port or passage, but allowing it to yield and open IOO IIO

the same wide open when the train-pipe presuure is increased for the purpose of reiilling said reservoir, substantially as described.

24. In a fluid-pressure brake mechanism, the combination of the train-pipe and auxiliary reservoir with a port or passage for normally maintaining communication between them, and a piston or valve subject to the outward pressure of a spring for controlling said port or passage and operated by varying the relative pressures of the train-pipe and auxiliary reservoir, the whole being adapted to hold said port or passage restricted to the dimensions of a small equalizing port or passage when the pressures in the train-pipe and auxiliary reservoir are substantially equal to open said port or passage wide open when the train-pipe pressure is slightly increased above that of the auxiliary reservoir and to completely close said port or passage when the train-pipe pressure is slightly reduced below that of the auxiliary reservoir, substantially as described.

25. In a Huid-pressure brake mechanism, the combination ot" the train-pipe, auxiliary reservoir, brake cylinder, and governingvalve device with au equalizing port or passage which eiects communication between the train-pipe and auxiliary reservoir when the main valve is at the service-port and the supplementary valve is holding said serviceport closed, substantially as described.

26. In a fluid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, brake-cylinder, and governing-valve device with two equalizing ports or passages from the train-pipe to the auxiliary reservoir, one of which is adapted to come into action when the governing-valve device is in its normal position and the other when the main valve is at the service-port and the supplementary valve is holding the latter closed, substantially as described.

27. In a Huid-pressure brake mechanism, the combination of the brake-cylinders, auxiliary reservoirs, controlling-valve devices, and the train-pipe with two main compressed-air reservoirs controlled by a cock or cocks for the admission of Huid-pressure into the train-pipe from either of said reservoirs at the will of the engineer, substantially as described.

28. In a fluid-pressure brake mechanism, the combination of the brake-cylinders, auxiliary reservoirs, controlling-valve devices, and the train-pipe with two main compressed-air reservoirs, and with a controlling cock or valve which, at dilt'erent positions of its movements, successively puts them into communication with the train-pipe, substantially as described.

29. In a fluid-pressure brake 1n echanism the combination of the brake-cylinders, auxiliary reservoirs, controlling-valve devices, and the train-pipe with two main compressed-air reservoirs, and with a controlling cock or valve provided with two ports, one of which when open discharges the contents of one main reservoir into the train-pipe and the other of which when open discharges the contents of the other main reservoir into the train-pipe, substantially as described.

30. In a ii uid-pressure brake mechanism, the combination of the brake-cylinders, auxiliary reservoirs, controlling-valve devices, and the train-pipe with two main compressed-air'reservoirs and a controlling cock or cocks, and with separate passages leading from said reservoirs to said cock or cocks, one of which passages is provided with a reducing-valve and the other is without a reducing-valve, substantially as described.

3l. In a fluid-pressure brake mechanism, the combination of a train-pipe, two main reservoirs,an air-pump, and a controlling cock or valve with two passages, 0 o', a reducing-valve, and a check-valve, o, substantially as described.

32. In a Huid-pressure brake mechanism, the combination of the brake-cylinders, auxiliary reservoirs, controlling-valve devices, and the train-pipe, two main compressed air reservoirs, and passages 0 o Q with a way-cock,P, provided with a through-port, p, and valvesurfaces p p2, adapted to operate with relation to said passages substantially as described.

In a ii uid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, brake -cylinder, and governing-Valve device with two main reservoirs communicating with the train-pipe by independent passages, and with a way-cock, P, provided with a through-pomp, and valve-surfaces p p2, and having the edges of said valve surfaces rounded or beveled, as shown at c c', substaniially as described.

34. In a Huid-pressure brake mechanism, the combination of the train-pipe, auxiliary reservoir, brake-cylinder, and governingvalve device having a main valve and supplelnentary valve with an air port or passage, II, leading from the train-pipe to the face of the main valve, an exhaust-port, G', communicating with the face of the main valve, a main valve provided with two through-ports, which, when it is at its normal position, open into t-he passages H and G', respectively, and a supplementary valve which, when in its normal position with relation to the main valve, holds said through-ports out of communication with each other, butA provided with a recess or passage which, in case of an outward movement of the supplementary valve with relation to the main valve, puts said through-ports into communication with each other, substantially as described.

35. In a fluid-pressure brake mechanism, the open duct J, extending from an air-space behind the piston G to the passage G, which leads from the auxiliary reservoir to the brake-cylinder, and arranged to act as an ejector or siphon to reduce the air-pressure behind said piston while 'air is flowing violently from the auxiliary reservoir to the brake-cylinder, substantially as described.

IOO

IIO

scribed.

36. In a fluid-pressure brake mechanism, the combination of the chamber J', the open duct J, and nozzle j with the piston 6 and passage G, substantially as described.

37. Ina fluid-pressure brake mechanism, the combination of the chamber J', the piston 6, the open duct J, nozzle j, and passage G, having its diameter reduced at the end of the nozzle, substantially as described.

38. In a fluid-pressure brake mechanism having means for suddenly exhausting the train-pipe through a valved port, 2, in the act of applyingthe emergencystop, the enlarged stem L, provided with the ample transverse passage N, arranged to come in line with the train-pipeand port aforesaid and aord a direct and unobstructed exhaust-passage for the train-pipe air when the governing-valve is at the emergency-port, substantially as described.

39. In a fluid-pressure brake mechanism, the open duct M, extending from a lower recess of the valve-casing to an exhaust-passage, through which air is discharged at great velocity, and arranged to act in the manner of an ejector or siphon to draw up and discharge collected water, substantially7 as described.

40. In a fluid-pressure brake mechanism, the combination of the main valve E, having the ports c g g', with a supplementary valve, E', having the passage g2, substantially as de- 41. In a fluid-pressure brake mechanism, the combination of the main. valve E, having the ports e g g, with a supplementary valve, E', having the passage g2, and with a spring, K, substantially as described.

42. In a Huid-pressure brake mechanism, the combination of the main valve having an elongated exhaust-passage, g, with a supplementary valve having an elongated exhaustpassage, g2, substantially as described.

43. In a fluid-pressure brake mechanism, the

combination of a casing having the passages G G', and a main valve having the port-s e g g', and a supplementary valve having the port g2, substantially as described. 44. In a Huid-pressure brake mechanism, the combination of a casing having the passages G G', and a main valve having the ports e g g, and a supplemen tary valve having the port g2, and a spring, K', tending to hold the supplementary valve in a normal position with respect to the main valve, but allowing it to be moved' in both directions therefrom by the application of sufficient force, substantially as described.

45. In a fluid-pressure brake mechanism, the combination of a main valve having a surface-channelLg, in communication with the exhaust-port G, and a supplementary valve having an internal passage, g2, open at both ends to the face of the valve, substantially as described.

46. In a fluid-pressure brake mechanism, the combination of a casing having opposite passages, 2 d, through its walls, and a springstem, L, enlarged to till the casing between said passages and provided with a tapering. opening through it in the plane of said passages, the larger end of said opening being on the side toward the passage d and always in communication therewith, and with an airchamber at the outer end of the governingvalve device, substantially as described.

47. In atluid-pressure brake mechanism, the combination of the local outlet-port 5 with the elastic tubular dust-shield S, substantially as described.

48. In a huid-pressure brake mechanism, the combination of the two valves E E with the spring K, the spring-holding device k, attached to the main valve, and the plates k k2 at the ends of the spring and operated by the piston-stem to compress the spring in both directions, substantially as described.

49. In aluid-pressure brake mechanism, the combination of the two main reservoirs, an air-pump, a passage lead-ing from the airpump to one of said reservoirs, and a passage leading from the air-pump to the other of said reservoirs and provided with a reducing-valve, substantially as described.

50. In a duid-pressure brake mechanism', the combination of the two main reservoirs, airpump, train-pipe,waycock or en gineers valve,

'and passages leading from each of said reservoirs yto said cock or valve, with a passage leading from one to the other of said reser- IOO voirs and provided with a check-valve, whereby the turning of said cock or valve to one position will vent air from one only of said reservoirs to the train-pipe, and to another position will vent air from the other reservoir to the train-pipe until the pressure in the two reservoirs is equalized, and will then vent from both of said reservoirs to the train-pipe, substantially as described.

THERON S. E. DIXON.

, In presence of W. M. HILL, HARRY BITNER.

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