US534401A - Fluid-pressure signal-valve - Google Patents

Description

(No Model.)

H. R. MASON.

PLUIE PRESSURE SIGNAL VALVE. No. 534,401. Patented Feb. 19, 1895,

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certain signal valve, which constitutes one of A UNITE-D t STAT-Es llefrrzivT i* OFFICE.

HARRY R. MASON, OF OAK PARK, ILLINOIS.

FLUID-PRESSURE SIGNAL-VALVE.

SPECIFICATION yforming part 0f Letters Patent No. 534,401, dated February 19, 1895. Application filed December 7, 1894. `Serial No. 53I|090 (No model.)

To all whom it Hetty concern:

Be it known that LHARRY R. MASON, a citizen of the United States, residing at'Oak. Park, in the county of Cook and Stateof Illi- Y nois, have invented a new and useful Im-.

provement in Fluid-Pressure Signal-Valves, of which the following is a specification.

My invention relates to improvements in a the principal features of duid-pressure signaling systems for railway-trains, and is usually located upon the .engine cab to be actuated, by signaling impulses in to operate the signal. v

My present improvement relates to a sig.

nal valve of the non-interference type, the

:name being given to valves of this particular class because they are-constructed to prevent' such interference, from rebounding signaling.

impulses as would causeundue repetition of the signal.

In Letters Patent of the United States No. 512,889, granted to me January 16,1894, I-

show, describe and claim a non-interference signal-valve, the non-interference principle being carried out with mechanism oper- I ating automatically, after the signal has been sounded once under the action of the direct impulse, to shut 0E the signal temporarily, whereby ,fluctuations of pressurein thesignaling-pipe, following upon the direct impulse, have no effect upon the signal. r

My present object is to provide a signalvalve with improved mechanism, which shall operate to prevent interference from rebounding impulses, in a train of any length and without the necessity of adjustment according to the length of the train, by causing such lowering of the signal-reservoir pressure unthe signaling-pipe,-

Byretarding the return of the signal-valve piston thedegree of pressure vented from the signalingreservoir is increased and the sigmaling-reservoir pressure thus lowered to a degree which will prevent its lifting the signal-.valve piston against the reduced 'counterpressure upon the vpiston, occasioned by rebounding impulses following the direct impulse.

' My object is', further, to provide mechan- .ism for'carrying out myinvention, of a simple, durable and economical construction.

The drawing vshowsavertical central section of Aa valve-device involving my improvements.

A is the valve which isformed, preferably, in two sections A Azvtting together with an intervening gasket t, The lower section'A2 is formed with a chamber s which, at its upper end, communicates through a cored passage-r with a pipe BV leading to the signaling or train-pipe, not shown. On the shell at r and communicating with the passage r is the usual train or signal pipe pressure gage, not shown. At the base and center of the chamber s is a port q surrounded by a valve-seat q', and leading toA a cored ,passage q2 which extends to a signal C, whichmay be a whistle, as shown. vExtending partway about the .valve-seat q is a portp leading to a passage --p which communicates with the signalingreservoir, not shown. In the upper part of Y the chamber s is an annular bushing s', and

working in said bushing is a movable abutment, preferably in the form of a piston, '11 upon a stem 'nf sliding through a sleeve or bushing supported by the part s2 in the chamber s. At its lowerend the stem 'n' is formed into a valve n2 to fit the valve-seat q and close the'port q, The piston n is out of immediate contact at its circumference with the bushing s' to afford an annular passagein the chamber s between opposite sides of the piston. This annular space is the only passage between the train-pipe and signalingreservoir, and, for the purpose of'illustration, is exaggerated in the drawing.

In the upper section A', and in open communication with the chamber s, is a chamber Z of smaller diameter than the chamber s and provided with an annular bushing Z.

In the" chamber lis a piston k having a stem la which IOO slides in a cored guide Z2 in the shell. The piston 7a fits the bushing Z loosely to permit air to pass between the chambers s Z around the circumferential face of the piston. Projecting downward from the piston 7c is a stem 7a2 provided in its end with a socket 71:3 which receives and slides over a lug n3 on the pisfn. Extending through the lug n3 is a transverse opening n4 enlarged in the vertical direction; and fastened in the sleeve or stem 7c2 and passing through the slot n4 is a cotter 7a4. Fastened against the under face of the shellsection A in the chamber s is a stop-plate 755 held in place by a screw 7s, The stop-plate 7s5 projects across the path of the pistou 7o and limits the movement of the latter in the downward direction. When the piston n is down, to seat with the valve n2 upon the valve-seat q', and the piston 7a rests upon the stop-plate 7x15 the cutter 7a4 extends through the upper part of the opening n4 leaving an appreciable space between the lower wall of the opening and the cotter. IVhen the piston n rises, as hereinafter explained, it moves a distance limited by said space before the lower wall of its opening n4 strikes the stop or cotter 7a4, and in its further rise the piston would have to raise the piston 7c.

In the upper part of the shell-section A is a chamber Z closed at thetop by a screw-cap i. Extending from the passagerto the chamber 'L' is a cored passage i2, and extending from the chamber Z to the chamber Z is a ventpassage i3. Around the passage i3 in the chamber t is a valve-seat Z4 upon which tits a check-valve t5. The check-valve is of predetermined weight and eftectually closes the passage t3. On the screw t is a stop t5 which limits the rise of the valve from the seat t,

In operation, air under pressure from the signaling-pipe B enters the cored passage r and fills the chambers s t'. From the chamber .s the pressure passes, somewhat slowly, around the piston n and through the passage p p to the signaling-reservoir; and pressure also passes from the chamber s around the piston 7t to the chamber Z. The chambers s Z t' and the signaling-reservoir are thus charged with air under a pressure equal to that of the signaling-pipe. The weight of the piston n and the suction eect against the valve a2 at the `port q, maintains the said piston and valve seated and the port q closed. The piston 7c rests normally upon the stop 705, and the valve is maintained normally closed by gravity.

All the conductors signalingT valves which I prefer to provide for my improved signaling-system are constructed with a view to venting with each operation a certain predetermined volume or degree of pressure with each operation,so that each time they are actuated the generated impulse will be the same. All

my conductors signalingvalves are constructed alike, so that in a train of any number of cars a signaling impulse will be initially ot' the same negative force no matter upon what car it is generated. A signaling impulse generated at a conductors signalingvalve in a long train is necessarily weaker, when it reaches the signaling-valve, than it would be in a short train. In Letters Patent hitherto granted to meIhave explained, and it is now well-known in the art, that a signaling impulse when it travels to the end of the signaling-pipe rebounds, the force of the rebound being proportional to the force of the direct impulse. As also explained in patents hitherto granted to me there is always danger when the signal has been actuated by a direct impulse that it will be actuated a second time by the rebounding impulse if no means are provided to preventit. The meansl provide in the present construction produce such venting or lowering of the signal reservoir pressure under the direct impulse that the reservoir pressure will be approximately as low as, or lower than, the pressure above the piston n when the rebounding impulse is felt in the chambers above the said piston. To accomplish this the piston fa, as I prefer to provide it, is made suil'iciently sensitive to rise and cause operation of the signal under an impulse generated at a conductors signaling valve in a train of,

say, eighteen cars,-eighteen passenger' cars being usually the limit in number allowed for any one train by railroads. Under a signaling impulse generated in a train of eighteen cars the piston n will rise to the stop 764, and when by venting through the port q the signaling reservoir pressure falls approximately to that in the train-pipe, the piston will drop and close the port q. The rebounding impulse will reach the piston, before there has been time for any material replenishment of the reservoirs, and a rebounding impulse will not lower the pressure above the piston n sufciently to cause it to be moved from its seat by the reservoir pressure.

The piston 7c may be said' to perform two functions, because in the rst place it presents a yielding counter-force to that which raises the piston n, and then when it has been moved from normal position by the force of the piston n, in the rise of the latter, it presents a yielding counter-force to that which lowers the piston n. Thus an impulse of greater force than that necessary to lift the piston 'n alone, causes the latter to litt the piston 7c, and expel air from the chamber Z to the chamber 'L' against the resistance of the Weighted valve t5. The greater the signaling impulse the greater the rise of the piston 7c, and the rise of the piston isV therefore proportional to the strength of the impulse. In order that the piston 7c may return to normal position air must pass around the said piston from the chambers to the chamber Z. The greater the rise of the pistons, therefore, the slower their return to normal position, and the longer the portq will remain open to vent pressure from the signaling reservoir.

In practice I prefer to so construct the apparatus that the piston a will be lifted only to the IOO IOC'

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stop k4-under a signaling impulse generated in atrain of from'fourteen to eighteen cars. In a shorter train of carsa signaling impulse will reduce the pressure above the-piston n so far below that in the signaling reservoir that the piston n will be raised to the stop 7a4 and then raise the piston k in the chamber Z, the force causing the pressure in the chamber Z to raise the weighted valve i5 and thus vent more or less of the pressure from the chamber Z. When the impulse has passed, and pressure rises in the train-pipe and above the piston fn, the lowering of the latter is retarded by the piston 7c, which can move, as stated, no faster than the pressure entering the chamber Z around the pistonlcwill permit. Pressure will vent from the signaling-reservoir to the signal until the valven2 is closed and the degree of venting isf commensurate with the rapidity of return of the pistons 'n 7c, or, primarily, with the force of the direct signaling impulse. Under an impulse generated in a train of from ten to thirteen cars the'piston lc will rise but slightly and retard the return of the piston 'n but slightly, and so on as the train is shortened the degree of rise of the pistons will be in proportion to the force of the direct impulse, which later will be, approximately, in inverse proportion to the number of cars in the train. In a train of from one to four cars the piston Zo will be lifted tothe top of the chamber Z and its return made proportionately slow. In every instance the pistons will be raised and the port q caused to remain open a length of time sufficient to vent enough pressure from the signaling-reservoir to prevent the rebounding impulse from causing a second rise of the piston n. It is of course desirable to economize air as much as possible and for this reason the parts should be adjusted with suflicient nicety to permit just enough and no more pressure to be vented from the signaling-reservoir than is necessary with each operation. Following the action of each direct impulse, pressure is equalized with desired quickness between opposite sides of the piston n by the passage around it of pressure from the train-pipe to the signaling-reservoir.

In its broadest sense the gist of my invention lies in providing mechanism which will operate automatically to retard the closing or return of the valve, at the outlet port to the signal, whereby under all conditions sufficient pressure will be withdrawn from the signaling-reservoir to prevent the piston from being raised by the rebounding impulse. My invention further consists, in providing retarding mechanism for the said valve which will be governed'in its action by the force of the direct or original impulse, so that under a comparatively strong impulse,which would be followed by a correspondingly strong rebound,the signaling-reservoir will be vented to a greater degree than under a comparatively weak impulse.

In carrying out my invention I employ the construction shown in the drawing, and I prefer it to any other construction, at present, because it is the best I have tried, and it operates Well. My invention, in spirit, however, may be carried out with mechanism variously modiiied, and I do not Wish itfto be limited in its broad sense to any particular construction of return-retarding mechanism for the valve. n

What Iclaim as new, and desire to secure by Letters Patent, isy 1. In a fluid-pressure signaling-system, the combination with a signal-valve device provided with valve-mechanism interposed between a signaling-pipe and a signaling-reser- Voir, and subject on its opposite sides to pressure therefrom, respectively, and normally closing an outlet from said reservoir to the signal, and movable from normal position to open said outlet under pressure from the said reservoir when the train-pipe pressure falls under a signaling impulse, of return retarding mechanism for the said valve-mechanism supplementing the action of the reservoir pressure to afford yielding resistance to the return of the valve-mechanism to normal position under the rise of pressure in the signaling-pipe following said impulse, substantially as and for the purpose Aset forth.

2. In a duid-pressure signaling-system, the combination with a signal-valve device provided with valve-mechanism interposed between a signaling-pipe and a signaling-reservoir, and subject on its opposite sides to pressure therefrom, respectively, and normally closing an outlet from said reservoir to the signal, and movable from normal position to open said outlet under pressure from the said reservoir when the train-pipe pressure falls under a signaling impulse, of return retarding mechanism for the said valve-mechanism governed in the extent of its retarding action by the force of the signaling impulse and supplementing the action of the reservoir pressure to afford yielding resistance to the return of the valve-mechanism to normal position under the rise of pressure in the signaling-pipe following said impulse, substantially as and for the purpose set forth.

3. In a fluid-pressure signaling-system, the combination with a signal-valve device provided with valve-mechanism interposed between a signaling-pi pe and a signaling-reservoir, and subjccton its opposite sides to pressure therefrom respectively, and normally closing an outlet from said reservoir to the signal, and movable from normal position to open said outlet under pressure from the said reservoir when the train-pipe pressure falls under asignaling impulse, of return retarding mechanism for the said valve-mechanism in the path of the said valve-mechanism to be engaged and moved thereby after the said valve mechanism has been moved a predetermined distance from its normal position,

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and supplementing the action of the reservoir pressure to afford` yielding resistance to the return of the valve-mechanism to normal position under the rise of pressure in the signaling-pipe following said impulse, substantially as and for the purpose set forth.

4. In a fluid-pressure signaling-system, the combination with the valve-device provided with a piston interposed between asignalingpipe and asignaling-reservoir and subject on its opposite sides to pressure therefrom respectively, and normally closing an outlet from the said reservoir to the signal, and movable from normal position to rise and open said outlet under pressure from the said reservoir when train-pipe pressure falls under a signaling impulse, of return-retarding mechanism at the said valve-device for the said piston, comprising a chamber having a vent opening, a movable abutment in said chamberat one side exposed to signaling pipe pressure and connected with the said piston, and a small feed passage between opposite sides of said abutment, the piston operating, when raised, to engage and move said abutment to expel air from said chamber through said vent opening and a check-valve at said vent opening, whereby the speed of the return of the piston and abutment to normal position is regulated by the speed of entrance of air to said chamber through said feed passage, substantially as and for the purpose set forth.

5. In a fluid-pressure signaling-system, the combination with the valve-device provided with a piston interposed between a signalingpipe and a signaling-reservoir and subject on its opposite sides to pressure therefrom respectively, and normally closing an outlet from the said reservoir to the signal, and movable from normal position to rise and open said outlet under pressure from the said reservoir when train-pipe pressure falls under a signalngimpluse, of return-retarding mechanism at the said valve-device for the said piston, comprising a chamber, a comparatively large vent passage from thechamber to the signaling-pipe, a check-Valve i5 at said vent passage, a comparatively small feed passage from the signaling-pipe to the said chamber, and a movable abutment in said chamber at one side exposed to signalingpipe pressure and connected with the said piston, the piston operating, when raised, to engage and move said abutment to expel air from said chamber through said Vent opening to the signaling-pipe against the resistance of the valve 115, and the return of the abutment and piston to normal position being regulated by the speed of entrance of air to said chamber through said feed passage, substantially as and for the purpose set forth.

6. In a fluid-pressure signaling-system,the combination with the valve-device provided with a piston interposed between a signalingpipe and a signaling-reservoir and subject on its opposite sides to pressure therefrom respectively, and normally closing an outlet from the said reservoirto the signal, and movable from normal position to rise and open said outlet under pressure from the said reservoir when train-pipe pressure falls under asignaling impulse, of return-retarding mechanism at the said valve-device for the said piston, comprising a chamber, a comparatively large vent passage from the chamber to the signaling-pipe, acheclc-valve t5 at said vent-passage, a comparatively small feed passage from the signaling-pipe to the said chamber, and a movable abutment in said chamber at one side exposed to signalingpipe pressure and connected with the said piston, the piston being movable for a predetermined distance independent of said abutment, and operating when raised beyond said predetermined distance, to engage and move said abutment to expel air from said chamber through said vent opening to the signaling-pipe against the resistance of the valve t5, and the return of the abutment and piston to normal position being regulated by the speed of entrance of air to said chamber through said feed passage, substantially as and for the purpose set forth.

HARRY R. MASO.

In presence of- M. J. FROST, J. H. LEE.

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