US 869323 A
Description (OCR text may contain errors)
No. 869,323. PATENTED OCT. 29- 1907.
' R. P. NOLAN.
AUTOMATIC WARNING SIGNAL FOR AIR BRAKE SYSTEMS.
APPLIOATION FILED NOV. 7, I906.
n'qvmt'rom wrmns fl v R.P.NOLA N.
I UNITED STATES PATENT OFFICE.
AUTOMATIC WARNING SIGNAL FOR Alli-BRAKE SYSTEMS.
Specification of Letters Patent.
PatentedOct. 29, 1907..
' Applicatio fil ed November 7, 190 6- Serial No. 34:2.431l
I To all whom it may concern:
Be it known that I, RICHARD PETER NOLAN, of Havelock, in the county of Peterborough, Province of On-- tario, Canada, have invented certain new and useful Improvements in Automatic Warning-Signals for Air- Brake Systems, of which the following is a specification. My invention relates to improvements in signal de- .valve, the details of the device-being more fully set forth and described in the accompanying specifications and drawings Figure 1- is a sectional view through the valve when closed. Fig. 2 is a sectional view when open. Fig.3
V responding parts in each'figure.
Of late many accidents have occurred owing to the.
is an elevation showing the complete device with the signal attached thereto.
In the-drawings like letters of reference indicate corfailure of the air brakes to operate in the various cars when simultaneously applied by the engineer. This has been due in some cases to the air gradually escaping and lowering the pressure to such an extent that the brakes will not operate. the pressure is suddenly lowered the air brakes will be automatically applied but very frequently a gradual lowering could take place without any effect being "produce'd on the brakes. A further cause of accident is the angle cock placed at each end of each car which frequently by jarring becomes'closed and so cuts off thatv car from the rest of the system. -.The airin this car may then be gradually reduced in pressure without any ef-- fect being noticed in the other cars. Sometimes a gage is attached tojeach car but it isevident that this is an unreliableinletlied of indicating the; condition of so vital a matter asthe air brake system and might easily be overlooked by the train crew. In my invention whenever-f the pressure falls below-a. given amount a loud warning signal is at once produced which will attract the attention of the train crew to the leakage. 4
Referring to the drawings A .is the valve the details of which may be varied the essential features being the movable valve disk a which is normally pressed'away Of course as is well known if shown the valve disk is cylindrical provided with a conical lower face and has a stem 2 secured thereto, the opposite end of which extendsfinto a slot provided in a nut g screwed in an aperture h in the lower side of the valve housing. Access is gained to the top of the valve disk through the housing by means of a holei' normally closed by a cap nut j screwed therein.' The upward movement of the valve is regulated and limited by means of a set-screw k extending through the cap nut and adapted to'abut the top of the stem e when the valve is in its uppermost position the stem 6 being extended beyond the upper side of the valve disk for this purpose. One side of the valve housing is connected by asuitable pipe I to one of the conducting'pipes m of the air brake system and the'opposite side'is connected by a similar pipe n to a suitable signaling device B which asshown is an air whistle, 'This however, may
be any form of signaling device which can be operated by the passage of airtherethrough.'
In carrying out my invention one ofthe valves will i be attached to the air brake pipes in each car. Under normal conditions the pressure of the air in the air brake pipe exerted on the top of the valve disk a will hold the same tightly against its seat b and prevent any passage of air through the valve. As soon however, as the pressure falls below a predetermined amount the compression spring e will lift the valve off its seat and permit theair to escape through the valve to the signaling device B operating the same to produce a loud that it will operate the valve when the pressure is lowered a predetermined extent and'yet have suflicient pressure to operate the brakes satisfactorily. Adjustment is provided for the tension in this spring by means of the nut 9 .whereby it the spring weakens in strength the'weakness may be made-up for by a greater compression. I
It will be observed that no matter how gradually the pressure lowers yet the valve will be lifted off its seat immediately on the pressure passing below the given point and I have found by testing that this valve will i i be opened and closed by a difference inpressure not exceeding one half pound per square inch. The pressure at which it would generally be desirable to have the valve operate would be fifty pounds per square inch but this obviously might be changed to suit different circumstances. v
It will be readily understood that while I have described with great particularity of detail one specific .warning signal. The strength of the spring 0 is such embodiment of my invention certain changes might be made therein within the scope of the appended claim ithout departing from the spirit of my invention.
What I claim as my invention is In an automatic warning signal for air brake systems, the'combination with the globe valve housing and substantially horizontal valve seat therein of a valve operating on 10 of the housing having a recess therein into whichthe through the top of the valve housing, a set screw extending through the same and adapted to limit the upward movement of the valve by engaging the stem thereof.
' Signed at Havelock, in the Province of Ontario,' this 29th day of October, 1906.
RICHARD PETER NOLAN. Witnesses:
'lnos. Bnxxn'r'r, S'rnrHnN BERNARD O'HARA.