US1084779A - Automatic fluid-brake. - Google Patents

Description

L, H. ALBBRS.

AUTOMATIC FLUID BRAKE.

APPLIOATION FILED JULY 22, 1913 1,084,779. Patented Jan. 20, 1914.

3 SHEETS-SHEET l.

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L. H. ALBERS.

AUTOMATIC FLUID BRAKE. APPLICATION FILED JULY 22, 1913.

FIG.E

Patented Jan. 20, 1914.

3 SHEETS-SHEET 2.

INVENTOR L. H. ALBERS.

AUTOMATIC FLUID BRAKE.

APPLICATION FILED JULY 22,1913. 1,084,779 Patented Jan. 20, 1914.

3 SHEETS-SHEET 3.

. WITNES INVENTOR 5 6&% d cm w shown my special cap as attached to one assa 'e-wa s and orts, thereb makin my a: v n

forming its required functions, in which:

valves,

piston?) operates is designated by the letter 7 the letter A; on the brake pipe side.

LOUIS H. ALBERS, OF ALBANY, NEW YORK.

AUTOMATIC FLUID-BRAKE.

Specification of Letters Patent.

atentcd Jan. .20, 191-1.

Application filed July 22, 1913. Serial No. 780,455.

I b all whom it may concern Be it known that I, Louis H. Animus, a citizen of the United States, residing at Albany, in the county of Albany and State of New York, have invented a certain new and useful Improvement. in Automatic Fluid-Brakes, of which the following is a specification.

The primary object of this invention is to effect certain important changes of a constructive nature over my former Patent No. 1,053,263, dated February 18, 1913, wherein I disclose andclaim an attachment cap for triple, control, and other air actuated valves applicable in the class of fluid brakes, and intended to prevent undesired quick action.

In this present invention my aim is to provide astructure. or attachment cap which is desi ned to be connected to and cooperate wit1 triple, control, and similar valves, in preventing undesired quick action, in which I dispense with the spring and slide valve incorporated in my said former patent, and accomplish the object sought after by means of adequately arranged pistons,

device simpler-in construction, and co nsequently ot' a lessened production cost over that type involved in my above referred to former patent.

I illustrate herewith by diagrammatical views three essential and well known posi tions assumed'by the mechanism in per- Figure 1 shows the relative attitudes of the respective coacting pistons and movable parts in what'is known as release position: Fig. 2 is a similar view showing the movable partsin service position: and Fig. 8 is a similar view with the movable parts in emergency position.

In the accompanying drawings I have type of triple or control valve involving the main piston 3, together with two slide one designated by the numeral 5 known as the main slide valve, and the other by the numeral 4 and known as the graduating valve, in which are the customary registering ports. The chamber in which the H, on the auxiliary reservoir side, and by The only alteration that will be necessary in the triple or control valve to which my improved cap will be applied, is the drillin; of a port g, one end of which terminates in the chamber H, and is opened or closed by the movement of said slide valve 5 the opposite end registering with a continuation, of more or less increased area, formed in the said attachment cap, and likewise designated therein by the same letter 1 In Fig". 1. which shows the combined mechanism in release position, air from brake pipeenters the valve body at port a, and flows simultaneously in four directions, viz: into.chan1ber A, which is the brake pipe side of piston 3, then through teed groove 41: into chamber H, which is in direct communication with the auxiliary reservoir or pressure chamber, not shown; through port a into chamber B, or top side of piston 1: from port a into port 6 and then into port a formed in the stem of piston 1, then to chamber G. or under side of said piston l, which side is always in direct communication with storage chamber or volume D a. into port 0, then into chambers E and F. which said chambers are always in direct communication with each other. amt positioned at the brake pipe side of piston 2. The port designatec {I connects the stem end of piston 1 with chamber G, which is on the auxiliary reservoir side of piston 2. This port 1 is cut oil from the atmosphere by the graduating valve 4, which is part of the main valve.when the main piston 3 is in release position. This being, accomplished by blanking port It in the main slide valve 5, which said port /b is in communication with port 9. This foregoing described construction insurcs one imrovement over m former )atent referred to, for if piston 2 he leaking past leather seat, or if stem of piston 1 be leaking past its seat, the air cannot escape to atmosphere and thereby cause a brake pipe leak. In the event of either seat leaking port 9 will be charged to brake pipe pressure. This will destroy the hold mg power of piston 2, as chamber G, always in communication with said port 9, will likewise be charged, thereby balancing pressures on both sides of piston 2.. the resisting function of piston 2 is not required so long as the main piston 3 is in release po sition, the p ossibility of a brake pipe leak is restricted to one graduating valve 4.

point, namely, pastthe Ports o, t, and exhaust cavity, and port a in slide valve 5, likewise registering ports '0, r, and s in main body 7 are all well known and familiar pars of modern equipments, they being here s 10WI1 merely for the purpose of aiding those skilled in the air brake art to readily follow the operation of my improved special attachment cap.

When a preliminary service brakepipe reduction is being made air from chamber A flows back into brake pipe, causing a drop in pressure on that side of main piston 3. This'reduction permits the air in chamber H, or auxiliary reservoir pressure, to move said piston 3 toward service position, which in so doing closes feed groove 0:, and also moves graduatingvalve 4 so that cavity connects ports h and n in slide valve 5. This connects port g and chamber G to atmosphere by way of port 0. Should istons 1 and-2 not be making a tight seal tie venting ofpressure from port g. and chamber (3 will instantly bring them into this position. Air in chambers B and a, volume D and ports a, o, and a, flows back into brake ipe.

. Fig. 2. shows the device in ull service position. If, when main piston 3 has reached the position above described, a still furt-her'service reduction is made, said piston 3 in advancing cannot travel past service position on account of holding power of piston 2. Said piston 2 obtains its power or force necessary to temporarily retard piston 3 by reason of the differential of' pressures acting on its opposite sides, chamber G being connected to atmosphere through port g, slide valve 5, graduating valve 4, and port 0 in valve body 7 while the air in chambers E and F is held at brake pipe pressure. This differential of pressures acting on opposite sides of piston 2 commences the instant piston 3 engages and moves slide valve 5, and. continues until said piston 3 moves back to service lap. \Vhen a service reduction is made in brake pipe pressure, the pressure on chamber H side of main piston 3 becoming greater than the pressure on brake pipe side or in chamber piston 3 is forced into service osition. .-In this position air in chamber H expands through port 4) in slide valve5 into brake cylinder, or application chamber through port r. If brake pipe reduction is stopped before pressures in chamber H and brake cylinder or application chamber equalizes, the pressure in chamber H will drop slightly below brake pipe and piston 3 will be moved back to service lap. This will cause graduating valve 4 to blank port g from atmosphere.

Fig. 3 shows the device in emergency position. l/Vhen brake is fully charged the pres sure in chamber B, which is the top side chamber C, are equal. However there is a differencein the areas of chambers B and C, proportionate with the space occupied by the stem of piston 1, which extends down through chamber '0. Since the'bottom of said stem is connected to and seats over port g, which said port is connected to atmosphere, piston 1 is not accurately balanced, but is held down on stem seat by means of gravity and also differences of areas exposed to air pressure.

In order to obtain the necessary differential' to overcome gravity, and likewise variable surface exposure to atmospheric pressure, the pressure in chamber B must necessarily be reduced below the pressure in chamber C. As this differential is not required during service application, proof piston 1 are reduced atthe same time.

If an emergency application is wanted it is necessary to lift piston stem -1 off its seat. At thispoint the function of volume D comes into service. An emergency application means a fast reduction, and the pressurein chamber B, being connected to brake pipe by large ports, falls'quicltly with the brake pipe pressure. As pressure in chamber B reduces faster than the pressure in chamber 0, which latter is directly connected to volume D, differential is built up on piston 1, owing to the pressure from volume D being trapped or delayed to a more or less degree by reason of the restricted area of port 6. Said port 1) is made proportional to size of volume D, and will permit pressure to flow from said volume back into brake pipe at a predetermined rate. r

As the rate of drop in chamber B exceeds rate of drop in chamber C, enough differential is obtained to overcome friction, gravity, and holding power of the stem of piston 1. This causes said piston 1 to automatically move upward, and two actions are accomplished thereby: First, port 1) is further restricted,.causing less air to flow further increasing differential on piston 1, and second, the stem of piston 1 is lifted off its seat, thereby connecting port g with chambers F and E, pressure from which will be vented to the atmosphere through said port g, also through slide .and graduating valves 5 and 4 respectively. By constructing port c smaller than ports 9, h, cavity is, and ports a and 0, it permits pressure in chambers E and F' to be vented quicker than port 6 can charge same, and as a consequence the holding power of piston 2 is destroyed by equalizing pressures on its opposite sides thereby balancing same. When this foregoing described action takes place, and main piston of piston 1, and the pressure on bottom side,

3, moving from some point between release from volume D to brake pipe, thereby vision is made so that pressure'on both sides and service, strikes the stem of piston 2, it encounters no retarding force, and quickly moves tot-emergency, pushing said piston :2 ahead of it. In this position port g i and g-hamber (-i are cut otl' from the atmosphere and connected to brake pipe through port a and chambers E and P If a service, or slower brake pipe reduction is made, port 1) is of ample capacity to permit pressure in, volume D escaping to brake pipe without obtaining enough dilferenlial to lift piston 1 oh its seat.

Port g in the cap portion 6 is of greater bore than its continuation in .main body This is necessary for the reason that when an emergency application is made, and piston 1 raises, chamber F in direct comuumication with chamber E, connects to port 9. As the portion of said port g in cap 6 is larger than the continuation in main body 7 pressure to a predetermined degree .is backed up into port g of said cap a and likewise in chamber G. This serves two purposes: It partially destroys the holding power of piston stem 1, thereby aiding pressure in chamber C to raise said piston l, and it partially destroys holding power of piston 2, by building up pressure in chamber G, thereby-balancing entirely, or nearly so, pressures on both sides of said piston 52.

Port 6 being made smaller than the portion of port (7 positioned in main body 7, chamber F E will not be. charged faster than portg of body 7 can relieve it.

There are two methods of balancing pressures on piston 2. Either by having both sides at atmospheric. pressure, or by building up pressure on both sides any where between atmospheric and maximum.

\Vhat I claim as my invention is:

1. An attachment cap for air valves positioned adjacent to the main piston; suitable chambers, passage-ways, and ports in said cap; a second piston in said cap provided with an apertured stem and operatable in one of said chambers; and a resistance piston in said cap positioned intermediateof the main piston and second piston held, when said second piston is seated, by a dit- 'i'erential of pressures created against itsoppositc sides to check the main piston at service position, and opratable, when the said second piston moves, by an equalization of pressures on its opposite sides to permit the 1 main piston moving to emergency position.

2. An attaelnnent cap for air valves positioned adjacent to the main piston; suitable chambers, passage-ways, and ports in said cap in communication with the brake-pipe and atmosphere; a gravity seated piston in said cap; and a retardant piston in said-cap positioned for reciprocal movement between the main piston and gravity seated piston.

.3. In an automatic fluid brake, a valve attaehmcnt or cap positioned adjacent. to the main piston; a second piston in said cap op-- eratable ina suitable chamber. said piston involving an apertured stem portion. both sides of said piston being subjected to brakepipe pressure; a resistance piston in said cap operatable in a suitable chamber intermediate of the main piston and second piston held, by a diflerential of pressures created against its opposite sides, to check the main piston at service position; a,nd means for creating a differential of pressures on opposite sides of said second piston whereby said piston is automatically moved, thereby equalizing pressures on both sides of the said resistance piston to permit themain piston moving to emergency position.

4. In an automatic fluid brake a valve attachment or cap positioned adjacent to the main piston, involving a second piston provided with an apcrtured stem portion; a third piston intermediate of the main piston and second piston, all three of Said pistons being operatablc in suitable chambers; and suitable passage-ways and ports connecting the several chambers, brake-pipe and atmosphere, whereby undesired quick action of the main piston is overcome by setting up a differential of pressures on opposite sides of said intermediate piston during a service application of the brakes.

In an automatic fluid brake a valve attachment or cap positioned adjacent to the main piston, involving a second piston provided with an apertured stem portion; a third )iston intermediate of the main piston an second piston, all three of said pistons being operatable in suitable chambers; and suitable ports and passage-ways connecting the several chambers,brake-pipe and atmosphere, whereby quick action of the main piston is permitted by destroying the differential of pressures created on opposite sides of said intermediate piston during an emergency application of the brakes.

61 In an air brake mechanism, a special cylinder cap or attachment positioned adjacent to the main piston of any distributing, triple, or control valve, involving a second piston operatable in a suitable chamber, said piston having an apertured stem portion; a passageway connecting the stem end of said second piston through said cap and main piston body with the main piston chamber, connection with the atmosphere being regulated by movement of the main piston; a third piston intermediate of the main piston and second piston carrying a projection adapted to be engaged by the main piston when it arrives in service position; a cham her on each side of said third piston, the chamber on one side bein supplied by brake-pipe pressure throng a restricted port and connected with the stem end of said second piston when the :latter is seated, and

with the said passage-way when the said scc- In testimony whereof, I aflix my sight 0nd p1st0n 1s unseated, and the chamber on tm'e 1n the presence of two \vltnesses.

the opposite side by a ort With the said first mentioned passage-W231; and a train brake LOUIS fxLBhlm 5 pipe connection leading to one side of the W itnesses r main piston and to opposite sides of the said H. WV. STEVENSON,

second piston. I A. H. CLARKE.

Q Copies of this patent, may b obtained for .flve cents each, by'addrssing ,the Commisuioner of .Patcms. v

Washington, D. O."

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