US410288A - Releasing attachment for automatic air-brakes - Google Patents

Description

(No Model.)

7 'E. J. LEWIS.

RELEASING ATTACHMENT FOR AUTOMATIC AIR BRAKES. No. 410,288

Patented Sept VIZ/77 \v I J n, PETERS, PhnlwLithngmphcr. Wanhinglnn. o.c

UNITED STATES ELLSWORTH J. LEWIS,

PATENT OFFICE;

0F wAREENTon, OHIO.

SPECIFICATION forming part of Letters Patent No. 410,288, dated September 3, 1889.

Application filed June 20, 1889x To all whom it may concern:

Be it known that I, ELLSWORTH J. Lnw s, a citizen of the United States, residing at VVarrenton, in the county of Jefferson and State of Ohio, have invented or discovered certain new and useful Improvements in Releasing Attachments for Automatic Air- Brakes, of which improvement the following is a specification.

My invention relates to means for facilitat ing and insuring the prompt release of brakeshoes from the wheels whenever required af ter being set, and, is more particularly designed for application in connection with what is ordinarily known as the Westinghouse quick-acting triple valve, in the operation of which air is discharged from the main air or train pipe, aswell as from the auxiliary reservoir, into the brake-cylinder in effecting the application of the brakesfo'r emergency stops. In brake apparatus of this type it has been found in practice that by reason of a considerable proportion of the volume of air used in making an emergency stop being admitted to the brake-cylinder directly from the train-pipe the volume of air taken from the auxiliary reservoir will sometimes be insufficient to reduce the pressure therein to such a degree as will admit of the return of the piston of the triple valve, by the restoration of pressure in the brake-pipe, to the position in which it effects the opening of the exhaustpassage for air from the brake-cylinder, and the piston is therefore liable to stick that is, to be held in position for retaining the brake'shoes in contact with the Wheels by the pressure remaining in the auxiliary reservoir after the application of the brakes.

The object of my invention is to provide a simple and effective appliance for automatically effecting a rapid and immediate reduction of pressure in the auxiliary reservoir coincidently with and through the'action of the restoration of pressure in the main air or brake pipe, which is made by the engineer for the purpose of releasing the brakes, thereby instituting such preponderance of pressure on the side of the triple-valve piston which is open to the brake-pipe as will insure the return of the piston to position for opening Serial No. 314,922. (No man.)

the exhaust from the brake-cylinder, and the consequent release of the brakes. To this end my invention, generally stated, consists in the combination, with a triple valve, of a supplemental-valve mechanism actuated by pressure from the brake-pipe 'and governing a dischargepassage from the auxiliary reservoir to the atmosphere.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure 1 is a longitudinal central section through a triple valve, illustrating an application of my invention; Fig. 2, a transverse section through the same at the line a: w of Fig. 1; Fig. 3, a plan or top view of the abutment-chamber; ;Fig. 4, a similar View of a portion of the drain-cup of the triple valve with the abutsment-charnber removed, and Fig. 5 a central section through the relief-valve chamber with 1 the relief-valve removed.

My invention is herein exemplified as applied in connection with a quick-acting triple valve for automatic brake mechanisms, which accords in construction and operation with that set forth in Letters Patent of the United States No. 376,837, granted and issued to George WVestinghouse, J r., underdate of J anuary 24, 1888, and, not constituting in and of itself part of my present invention, need not be herein at length described. In the practice of my invention I provide a chamber which is fitted with a movable sides thereof with the main air or brake pipe and with a supplemental reservoir, respectively, a small charging groove or passage be in g formed past or through the abutment for the supply of air under pressure from the brake-pipe to the supplemental reservoir.

passes freely through ,a discharge-valve, controlling a port or series of ports leadin g from the abutment-chamber to the atmosfitted a disk, which bears against the oppoend of the abutment-stem bears against a reabntment, and communicates on opposite.

The abutment is fixed upon a stem which phere, and through a chamber in which is lief-valve, which opens outwardly from the. piston-chamber and controls a discharge-pas sage opening into said chamber and leading site side of the discharge-valve. The outer from the triple-valve-piston chamber at a point therein so located that the opening of the discharge-passage will be covered and closed by the triple-valve piston when in the position which it occupies during the periods in which the brakes are off or released. The discharge and relief valves are provided with springs, which act in conjunction with the pressure upon said valves to hold them normally to their seats.

Under the above construction, which may be located in any convenient position relatively to the triple valve proper, air under pressure passes from the brake pipe through the charging-passage into the supplemental reservoir,'and fills the same at a pressure therein equal to that in the brake-pipe. Then a reduction of pressure is made in the brakepipe to efiect an application of the brakes, air escapes from the supplemental reservoir through the charging-passage, reducing the pressure in the supplemental reservoir in an equal degree, the discharge and relief valves remaining in their normal position of closu re.

Upon the restoration of pressure in the brakepipe to release the brakes the increased pressure upon the inner side of the abutment moves the same outwardly, thereby unseatin g the reliefvalve and admitting air from the ordinary auxiliary reservoir through the passage leading from the triple-valve chamber to the chamber above the dischargeyalve, whereupon the air thus admitted, if of greater pressure than that in the brake-pipe, unseats the discharge-valve by its preponderance of pressure upon the disk above the latter and escapes into the atmosphere, thereby imme diately reducing the pressure in the auxiliary reservoir below that in the brake-pipe, and thus effecting a preponderance of the latter pressure upon the triple-valve piston, by which the same is returned to release position and the brakes released. The discharge and relief valves are then closed by their springs, a closing pressure from the brake-pipe being also exerted upon the discharge-valve, and

- the parts are in readiness for the next succeeding operation.

Referring to the drawings, 1 have illustrated my improvement as connected directly with the casing of the triple valve, by which a simple and compact construction is attained and pipe-connections wholly dispensed with. The cap or drain-cup 19 of the triple valve is surrounded by an annular supplemental reservoir 82, which is preferably formed integral with the drain-cup, and is suitably recessed to clear the bolts by which the draincup is secured to the triple-valve case 10. An abutment-chamber83, which is open at its inner end, is fitted into an opening on one side of the supplemental reservoir, and is secured thereto by bolts passing through a flange 84, which is formed around its top, being faced off truly on its inner side to make a tight joint with the adjacent surface of the reservoir 82. A movable abutment 84,which in this instance is in the form of a piston, but which may, if preferred, be a flexible diaphragm, is fitted, with a comparatively short range of movement, in the chamber 83, a small charging groove or passage 85 being formed in the Wall of the chamber, and extending from its open inner end to a point beyond the outer limit of the traverse of the piston. When a flexible diaphragm is employed, the charging-passage may be formed in the same in lieu of in the wall of the chamber. A port 86 is formed in the shell of the drain-cup 19 below the abutment-chamber, through which port and through the passage 85 air from the brake-pipe, which communicates by a passage 18 with the drain-cup, is supplied to the res ervoir 82 through the chamber 83 and through a port 83*,leading therefrom to the reservoir. A chamber 87 is formed in the abutmentchamber 83 adjacent to its outer end, and a series of ports 88, surrounding the chamber 87, communicate at their inner ends with an annular passage 89, leading into the abutmen tchamber 83, and at their outer ends are open' to the atmosphere.

A valve-chamber 90, closed at its'outer end by a removable cap 91, is formed upon the outer side of the head of the abutment-chamber 83, said valve-chamber communicating with the piston-chamber 87 by a port 91, Fig. 5, controlled by an outwardly-openin g relief-valve 92, and communicating above said valve with the piston-chamber 11 of the triple valve by a passage 93, which opens into the chamber 11 at a point in line with the triplevalve piston 12 when the latter stands in position, as shown in the drawings, to effect the release of the brakes-that is to say, when the slide-valve connected to the piston 12 opens the exhaust from the brake-cylinder.

The piston 84 is fixed upon a stem 9+1, which passes freely through a discharge-valve 95, controlling the dischargeepassage 89 and connected ports 88, and through a disk 96, which is fitted to traverse in the chamber 87 and bears against the outer side of the dischargevalve 95. The outer end of the piston-stem 94 abuts against the adjacent end of the stem 97 of the relief-valve 92, the portion of the stem 97 on the inner side of the valve being Winged or formed with lateral recesses, so as to afford passage for air from the chamber 90 to the chamber 87 through the port 91" when the valve 92 is unseated. A helical spring 98 bears against the relief-valve 92 and against IIO 410,288 r p 3 I the. port 86, passage 85, chamber 83, and port .83 into the supplemental reservoir 82, charging the same to a pressure equal to that in the brake-pipe and instituting an equilibrium of pressure on opposite sides of the movable abutment 84. The discharge-valve 95 is held to its seat by its spring 99 and by the pressure of the air admitted from the brake-pipe,

and the relief-valve 92 is likewise held seated by its spring 98. The reduction of pressure made in the brake-pipe and drain-cup in applying the brakes effects a corresponding reduction of pressure in the abutment-chamber 83 and supplemental reservoir 82, the air returning therefrom through the passage 85 and port 86 and maintaining the equilibrium of pressure on the opposite sides of the abutment 84. The inner end of the passage 93 is now uncovered by the outward movement of the triple-valve piston 12, and the auxiliary reservoir pressure on the inner side of said piston is transmitted through said passage to the chamber 90 of the relief-valve 92.

Upon the restoration of pressure in the brake-pipe and drain-cup, which is made by the engineer to release the brakes, the preponderance of pressure upon the inner side of the abutment 84 moves said abutment outwardly, as the increased pressure cannot gain access through the charging-passage 85 sufficiently fast to maintain the equilibrium of pressure on the abutment 84 by filling the chamber 83 and reservoir 82. In the outward movement of the abutment 84 its stem 94 unseats the relief-valve 92 and admits air from the passage 93 and valve-chamber 90 to the piston-chamber 8 7, whereupon, if the auxiliary reservoir pressure behind the piston 12 be greater than the brake-pipe pressure in the drain-cup acting on the opposite side of the piston, so that the return of the latter to eifect the release of the brakes is prevented, such higher pressure acting upon the disk 96 unseats the discharge-valve 95, and the excess of pressure is discharged into the atmosphere through the passage 89 and ports 88, thus instantly removing the resistance to the backward movement of the triple-valve piston 12, which is coincidently returned by the brakepipe pressure to releasing position, in which, through the slidevalve which it actuates, it opens the usual discharge-opening from the brake-cylinder to the atmosphere and eitects the release of the brakes.

It will be observed that the device is wholly automatic in its action, and while operative in all cases to relieve such excess of auxiliaryreservoir pressure as would hold or stick the triple-valve piston it does not involve any waste of air, as it discharges such excess only, the discharge-valve being closed by the pressure on its inner side as soon as such pressure, which will be the same as or slightly less than the brake-pipe pressure exceeds the auxiliary reservoir pressure, whic 1 resists the releasing movement of the triple-valve piston.

It will be further obvious that while the device is most desirably'applicable in direct connection with a triple valve, as shown,it may, if desired, be otherwise located relatively thereto, being provided with proper connections to the brake-pipe and to the triple-valvepiston chamber, respectively. I

I claim as my invention and desire to secure by Letters Patent 1. In an automatic brake mechanism,the combination, with a triple valve, of adischarge-passage for .air under pressure from an auxiliary reservoir to the atmosphere, and a supplemental-valve mechanism actuated by pressure from a brake-pipe and controlling said discharge-passage, substantially as set forth.

2. In an automatic brake mechanism, the combination, with a triple valve, of a mova-- ble abutment which is subject to variations of brake-pipe pressure on opposite sides, a relief-valve controlling a discharge-passage for air under pressure from an auxiliary reservoir to a discharge-valve, and located in position to be unseated by movement of the abutment, a discharge-valve controlling a passage for air from the relief-valve opening to the atmosphere, and a disk actuated by pressure delivered by the relief-valve and adapted to unseat the discharge-valve, substantially as set forth. 7

3. In an automatic brake mechanism, the combination, with a triple valve, of an abutment-chamber communicating at one end with a main air or brake pipe, asupplemental reservoir communicating with the opposite end of said chamber, an abutment fixed upon a stem and fitted to move in said chamber, a charging groove or passage establishing communication between opposite sides of the abutment, a relief-valve controlling a passage for air from an auxiliary reservoir to a discharge-valve, said relief-valve being located in position to be unseated by the movement of the abutment-stem, a discharge-valve controlling a passage from the relief-valve to the atmosphere, and a disk subject to pressure delivered by the relief valve and bearing against the discharge valve, substantially as set forth.

4. In an automatic brake mechanism, the combination, with a triple valve, of a supple mental reservoir adjoining and exterior to the drain-cup of the triple valve, an abutmentchamber closed at its outer end and fitting an opening in the supplemental reservoir, a port leading from thedrain-cup to the abut ment-chamber, a port leading from the abut ment-chamber to the supplemental reservoir, a valve-chamber and a disk-chamber located on the outer and inner ends of the head of the abutment-chamber, respectively, a reliefvalve controlling an opening or port from the valve-chamber to the piston-chamber, a piston fitted to Work in the abutment-chamber and having a stem which bears against the stem of the relief-valve, a discharge-valve fitting freely on the abutmentstem and con-'" IIO of its top, which abuts against the drain-cup casting, said openings being adapted to communicate with a triple-valve-piston chamber and With a supplemental reservoir, respectively, substantially as set forth.

In testimony whereof I have hereunto set my hand.

ELLSVORTH J. LEWIS.

Vitnesses:

J'. SNoWDEN BELL, W. B. CORWIN.

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