US1584363A - Method of operating brakes - Google Patents

Description

May 11 1926. 1,584,3(53

T. M. FRE-EBLE METHOD OF OPERATING BRAKES Filed March 25, 1925 msg v w o 3 g/X I INVENTOR Patented May 11, 1926,

srres THOMAS M. FREEBLE, OF ROCHESTER, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO r'rrur CARL SGI-IUSTER, F PITTSBURGH, PENNSYLVANIA.

METHOD OF GPERATING- BRAKES.

Application filed March 25, 1925. Serial No. 18,129.

The present invention relates to methods of operating brakes on'railway trains, and is particularly adapted-for use on trains of considerable length, such for example, as freight trains. v

The flexibility of control of a railway train by the use of air brakes is reduced as the length of the train is increased. This is largely due to the interval which elapses between the times of response of brakes at opposite ends of the train when the control valve in the engineers cab is set.

A particularly serious objection to the methods hitherto employed is illustrated in the case of a freight train approaching a warning signal which is actuated to indicate clear track just before the signal tower is reached. It frequently happens that the brakes are applied and the train speed is checked to a low rate before clear track is indicated. Under the present methods of operation it is necessary to completely stop the train before increasing the speed. The reason for this is that it is impossible to release the brakes on the rear of the train simultaneously with or before releasing the brakes at the head of the train. That is, under the present methods the brakes on the rear of the trainwould be still set when the head of the train is running free. It is obvious then, in the example cited, that an attempt to increase the speed of the train would result in pullingthe train apart. Because of this deficiency of the ordinary systems of brake control, much time is lost by needlessly stopping and starting long freight trains.

I provide a method of operation which permits long trains to be slowed to a low rate of speed and then brought back to running speed without the necessity of stopping and starting. This flexibility of control is obtained by releasing the brakes adjacent the rear of the train before releasing those adjacent the head end of the train. The releasing action travels sequentially from the rear of the train toward the front of the train at a rate depending upon the time taken to efiect a change of pressure in the train line. It will be understood that no attempt is made to apply the brakes in this manner because of the danger of rupturing the train, the brakes being applied sequentially from the front of the train toward the rear.

Figure 3 illustrates a method of valve connections which may be employed if a standard control valve is used.

Referring first to Flgure 1, there is shown an engine 2 provided with an air control valve 3 by which'the air pressure in a train line 4 or an auxiliary line 5 may be regulated. The air required for the op eration of the brakes is supplied to the control valve 3 by a line 6 from a storage tank 7 supplied by an air compressor 8.

The standard train line 4: is connected by I hose connections 9 to pipes 10 on the various cars 11. The pipes 10 serve the triple valves 12 connected to individual air tanks 13 on the cars 11. This is customary equipment on railway trains.

The auxiliary line 5 is likewise connected by hose connections 14: to auxiliary pipes 15 on the various cars 11. 15 and hoses 14L constitute an independent conduit running the length of the train. At the end of the train the hose 9 on the standard train pipe 10 is connected to the hose 14 on the auxiliary pipe 15 thereby forming a complete air system from the con trol valve 3 to the rear of the train and back to the control valve'3.

The control valve 3, as illustrated diagrammatically in Figure 2, is provided with a valve body 16 having a rotatably mounted plug 17 therein. The body 16 is illustrated as having an air inlet port 18 leading from the air line 6, a port 19 leading to the auxiliary line 5, a port 20 leading to the regu lar train line 4, and ports 21 and 21 leading to the atmosphere. The plug 17 may be turned to any desired position by a handle 22. The plug 17 is provided with a passage 23 which serves to interconnect the ports in the body 16.

If the train is long and it is desired to release the brakes, before a dead stop is reached, so that the train may get under way again, the handle 22 is turned to the position illustrated in Figure 2. Air from the tank 7 flowing through the passage 23 The auxiliary pipes in the valve, is admitted to the auxiliary train line 5 and increases the pressure in the standard train pipes 10 at the rear of the train. The triple valves 12 then operate and the brakes are released first at the rear of the train and the train closes up. Should steam then be admitted to the engine there is no danger of pulling the train apart for the rear cars are running free. Thus I provide a flexible method of operating air brakes on long trains. One of the distinct advantages of my method lies in the fact that the brakes may be applied and released in the usual manner if the train is short. That is, the handle 22 may be turned to the usual positions of lap, service, release and emergency, without using the auxiliary line 5.

Figure 3 illustrates a standard air control valve 24, bypassed by the auxiliary line 5 having a separate valve 25 conveniently placed therein. By this arrangement it is not necessary to have the special port 19 for the auxiliary line 5 shown in Figure 2 in the main control valve 245, since air may be admitted to the auxiliary line 5 through the separate valve 25 if it is desired to effect a release of brakes on the rear of the train prior to releasing those on the head end.

lVhile I have described my invention with reference to a particular embodiment, it will be understood that the invention is not limited thereto, but may be otherwise embodied within the scope of the following claims.

I claim:

1. The method of operating a brake system on a train which comprises releasing the brakes sequentially from the rear of the train toward the front of the train, substantially as described.

2. The method of operating an air brake system on a train which comprises supplying air progressively from the rear to the front of the train for the, release of the brakes, substantially as described.

3. The method of operating a brake system having a plurality of brake operating means and afiuid pressure line connecting said operating means which com-prises releasing the brakes by first supplying fluid under pressure to the brake operating means at the rear of the train and permitting sequential release of the brakes toward the front of the train by the increase of pressure toward the front of the train in the said fluid connecting line, substantially as clescribed. a

l. The method of operating a trainbrake system having a plurality of brake operating means responsive to a fluid pressure and a fluid pressure line connecting said operating means which comprisesregulating the pressure in the fluid pressure line to effect a sequential operation of the brake operating 7 means to release the brakes from the rear of the train toward the front of the train, a

substantially as described.

The method of operating a brake system on a train of coupled cars each having brakes and brake operating means which comprises applying the brakes sequentially from the front of the train toward the rear thereof to reduce the speed of the train and releasing the brakes sequentially from the rear of the train toward the front thereof to permit increasing the speed of the train, substantially as described.

6. The method of operating a brake sys I THOMAS M. FREEBLE.

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