US1674933A - Release valve - Google Patents

Description

June 26, 1928.

. S. E. TURNER RELEASE VALVE Filed Jan. 10, 1927 2 Sheets-Sheetl June 26, 1928.

S. E. TURNER RELEASE VALVE Filed Jan. 10, 1927 2 Sheets-Sheet 2 W W M QQF v Patented June 26, 1928.

UNHEQ STATES PATENT GFFlQl-l.

SAMUEL E. TURNER, OF WICI'IITA FALLS, TEXAS, ASSIGNOR T0 PANHANDLE REFINING COMPANY, OF WICHITA FALLS, TEXAS.

RELEASE VALVE.

Application filed January 10, 1927. Serial No. 160,229.

My invention relates to air brake systems for railway trains. It has for its object the production of an automatic release valve which will prevent sticky or faulty operation of the triple valve; will force a triple valve piston to at once release; to reduce auxiliary and cylinder pressure to a predetermined point only, and thereby relieve the excessive presure of brake shoes until the triple valve releases, which should be practically simultaneously; to enable the engineer of a train to release the brakes more quickly than heretofore; to enable the engineer of a train to handle the brakes so as to prevent surging of cars; by means which will be set forth to partially prevent brake burns, which in numerous instances due to this, cause wheels to burst and thereby wreck trains; to force the triple valve to at once release by obtaining an 8-lb. differential on the piston of triple valve thereby eliminating the sticking of this piston which stuck condition is one of the principal cau.:es of slid flat wheels; and to provide an automatic release valve that will not operate until a reduction of fifteen pounds in the wheel pressure of train line is made.

The present invention is applicable to the present air brake systems in common use on railway trains at this time,'of which the principal features necessary to an understanding of the present invention are the following; air suitably compressed is conducted to a main air reservoir, usually carried on the locomotive and connected through a train pipe coupled between cars 'tothe brake cylinders and auxiliary reservoirs throughout the train. The main air reservoir contains air at a pressure in excess of the pressurecontained in the auxiliary reservoirs and is controlled by means of an engineers brake valve, which regulates the flow of air into the train pipe and auxiliary reservoirs, to charge the train pipe and release the brakes, and also to exhaust from the train pipe to the atmosphere, or equivalent reduction in pressure, for applying the brakes. The train pipe extends the entire length of the train and in every'case it is by varying the pressure in this pipe that the brakes on each car are automatically applied and released. In the branch pipe from the train pipe. to each auxiliary reservoir is a so called triple valve which has three functions, namely: it charges the auxiliary sticky I reservoir, determines the quantity of air admitted to the brake cylinder for applying the brakes, and effects the discharge of air from the brake cylinder to release the brakes. In ordinary'service the pres. aure in the train pipe is reduced from (S t-o 8 pounds, in a slowing down of train, and fifteen to twenty pounds in making a regular stop, and in an emergency case it is suddenly reduced to zero by opening a large sized port to the atmosphere. When the train pipe pressure is thus reduced connection between the train pipe and the auxiliary reservoir-is cut OE and air under pressure from the auxiliary reservoir then enters the brake cylinder and sets the brakes. The pressure then in the brake cylinder would be at the amount caused by the equalization of the auxiliary and cylinder which according to the size of the two chambers would be at about fifty pounds. This lifty pounds is at a supposed piston travel of seven inches. In releasing the brakes the pressure in the train pipe is increased, causing communication between the auxiliary reservoir and the train pipe to be reestablished, and the air in the brake cylinder to exhaust into the atmosphere; It will be obvious from this statement that when the triple valve sticks or acts sluggishly, it produces serious interference with the normal action of the brakes and accordingly the principal object of this invention is to provide means whereby the perfect control of the train may at all times be retained by the engineer, by forcing the triple piston to immediately act. This object is obtained by obtaining a differential in the triple piston of up to eight pounds per square inch, this difi'erential to take place immediately on an increase of three pounds pressure in train line.

I attain my objects as follows: I provide an automatic auxiliary release valve controlled through the same train pipe that operates the triple valve and connected to it by separate cross over pipe and by means of this auxiliary valve I produce a differential of up to eight pounds on the triple valve as soon as an increase of three pounds in the train pipe pressure is obtained; This eight pound differential is obtained by reducing the auxiliary reservoir pressure to forty-two pounds which is the maximum reduction that can be made. By reducing the auxiliar y and thereby the brake cylinder presssure right as shown in Fig. 2.

to the predetermined pressure'of forty-two pounds I relieve the excessive pressure of the bra (e shoes until the triple valve releases, whichis practically simultaneously, and by operating on a three pound differential in the manner stated I produce a quick release of the brakes when desired by the engineer, and as all brakes set and release promptly on this three pound differential, surging of cars can be easily prevented. Brake burns are also prevented by the use of these pressures in the manner stated.

One of the principal objects to be attained by the use of this device is the prevention of slid-fiat wheels, which is attained in the manner stated above for prevention of brake burns.

My invention is illustrated in the accompanying drawings, in which Fig. 1 is a side view of a portion of the train pipe and auxiliary valve, the triple valve and connections and the brake cylinder on a car, together with my auxiliary release valve applied thereto.

: Fig. 2 is a longitudinal vertical section through the release valve shown in Fig. 1.

Fig. 3 is a detail view of latch i'i'icchanism vhich may be substituted for the spring arrangement l5 of Fig. 2.

' Fig. 4 is a diagram showing connections from the cylinder of my automatic valve into and through the auxiliary reservoir 2 and the brake piston cylinder 3.

Referring to the drawings in detail, 1 is the train pipe, 2 is the auxiliary reservoir, 3 is the brake cylinder in which operates the brake piston, 4 is the triple valve, 5 is the branch pipe connection from the train pipe to the triple valve 4, and thence to the auxiliary reservoir; 6 is the usual cut-oli' valve in said branch pipe 5, and 7 represents in its entirety ,my new automatic release valve mechanism. The operation of the parts 1 to 6 inclusive will be understood from the foregoing recital, as well as the essential features of the mechanism involved. These parts are familiar to'those skilled in the art and need not be described in detail. The construction and connections of the auxiliary reservoir release valve '3' may be described as follows Referring to Fig. 2. 8 is the valve cylinder and 9 is an auxiliary cylinder; these parts being usually made of gray castings secured together as shown. Cylinder 8 contains chambers 10 and 11. The chamber 10 has a closed head and the chamber '11 is closed by means of a detachable head 12, having a central hub 13 containing a slide bearing 14 for the stem 15 of piston '16 working within a liner 1? in the chamber 11. Surrounding the stem 15 is a compression spring 15 which tends to keep the piston 16 over to the The piston 16 bears against a' ring flange 18 which 'supports the two chambers 10 and 11, and the liner 17 as well as the wall of cylinder 8 is perforated at 19, the opening being threaded through the cylinder at 20 for a purpose which will be presently described. The cylinder 8 is also bored out and threaded at 21 to receive a piece of brass tubing 22 closed at its lower end except for the seat 23 of a check valve 24, the stem 25 of which extends up through the tubing and at its upper end carries a perforated guide disk 26, traveling in the tube and between which and the lower end of same there is interposed a coil spring 27, which tends normally to close the check valve.

The auxiliary cylinder 9 contains a liner 28, which together with the walls of the cylinder is drilled at 29-30 to form exhaust ports for the chambers 3132, above and below the piston 33 working in the cylinder. This piston 33 is fixed 'upon a spindle or stem 34, carrying at its lower end a check valve 35 situated in an opening 36 adapted to connect the chamber 32 with the auxiliary. A coil spring 37 extends between screw, or equivalent means. The upper end of the cylinder 9 communicates with the interior of the chamber 10 by means of a port or channel 40, shown as closed by means of treadle valve 41 hinged to one side of its seat in the brass bushing or liner 1'? and held closed when piston 16 is in the position as shown in Fig. 2. Stem 42 extends down from this valve into the spindle 34, these parts being in alignment and sufficient play being allowed to permit of the treadle valve rising and falling on its hinge. Between the collar 39 and a perforated disk or ring 43 on the valve rod 42 a coil spring 44 is maintained under compression. Finally the piston 33 is provided with ports 45 and 46 which co-operate with the cylinder ports 2930. It might be added that the spindle 34 is advantageously made of a piece of brass tubing and the piston 33 may also be called an atmosphere port lining valve, which operates with the spindle 3 The spring 37 requires 5 pounds pressure to compress inch when extended. The spring 44 requires 3 pounds pressure to compress it inch. The treadle valve rod 42 extends downward 1 inches in the tubular spindle 34and carries a spring seat 43.

The piston 16 carries a piston ring 16 and has a inch stroke which is SLlfllClGllt to allow treadle valve 41 to open and thereby es Illi') .i lii 3 is as followsz Referring to said Fig.

3, 101 is the latch, which is carried on post 105' and secured to said post by a bolt- 109 on which it is pivoted. 102 is a spring which connects the end of the latch to cap 12 of cylinder 8. 103 is the piston itself. 104 shows the contour of the back side of the piston on which the end of latch 101 works. In the contour of the annular raised cam portion of the back side of the piston, 107 is an annular cam surface inclined or ccned at a small angle from the plane of the piston, to receive and hold the point of the latch when in normalposition. 103 represents a dished cam surface inside this holding surface of the piston, into which the latch 101 is forced when the piston is pushed to the left of an inch.

The operationof this latch in general is follows: 1

Whenever 20 lbs. reduction of air is made in the chamber 11, the pressure in the piston chamber 10 is suflicient to extend spring 102. This extension of the spring allows the point of the latch 101 to be forced off from the contour surface 107 of the piston onto the steeper contour 108, which allows the piston to be forced over to the A inch required, the balance of forces being between the spring 102 on the one side and the cam action between 101 and 108, the latter being due to the movement of the piston 16.

Referring to Fig. 4 which is explanatory of the operation of the general assembly herein described, including parts both old and new, 9 is the automatic release valve cylinder which is threaded and screwed into the walls of auxiliary reservoir 2, 140 is an air brake port from the auxiliary reservoir to the triple valve, which upon the lining up of this port and port 150 (which is an air port from the triple valve to a one inch pipe 60) by the movement of triple piston 100 allows air to flow back through this one inch pipe 60 into the brake cylinder 3. In release position the air would flow back in reverse direction through port 150, through opening to the atmosphere 110; port 140 would then be closed. A feature in connection with the release of brakes as described above is the reverse action of the air being released to the atmos phere. -This atmosphere port has a inch pipe on which is placed what is called a re raining valve and when this valve is closed by the trainmen, it holds air in the cylinder vwhile the auxiliary reservoir charging.

Tuis retaining device is used only onthe mountain divisions of certain railroads and the action of the automatic air brake release valve would not aid or hinder in its duties when i ised. Ordinarily the retaining valve is left open and air escapes directly to the atmosphere. r

The operation of my valve 7 thus described is as follows:

Air pressure is supplied from the engine through a train pipe 1,. flowing equally through the triple valve 4 into the auxiliary reservoir 2 and intov the first cylinder 8 of the release valve 7.. It should be remarked in passing that the release valve is connected with the auxiliary reservoir 2 by means of the threaded. neck 47 on the casing 9, and it is connected to the train pipe by means of twin couplings 48-49, tapped into the opening 20,-

and secured around the body of the brass tube 22, respectively. T couplings 5051 with a valve 52 between them complete the connection.

With the inflow of air referred to through the connections 5 and 6 and 5051, the air pressure in the train pipe or line, the auxiliary reservoir, and the first part of the automatic release valve would be all the same, on most roads under a pressure of 70 pounds per square inch.

The position of the different parts of the valve will then be as follows:

Position 1. Uharging.Piston -16 of part 1 would be over against flange 18 and spring l5 would be extended. Check valve 24 would be open, the spring 27 compressed. Treadle valve 41 would be closed; treadle valve spring 44 would be compressed and atmosphere port valve spring 37 would be extended. Check valve 35 would be closed.

Position 2. AppZication.-vVhen a 20 lb. service application is made air flows out of chamber 11 of cylinder 8 of release valve and not out of chamber on account of check valve 24 being closed. This forces piston 16 inch to the left, in Fig. 2 until the stem has reached its limit in bearing 14. This allows piston 16 to uncover valve 41 which is then forced open by spring 44 allowing air to flow out of chamber 10 into chamber 31 of cylinder 9, which equalizes in these two chambers at 43 lbs.

The release valve parts will then be in the following position:

Check valve 24 is closed with spring 27 extended. Piston 16 with stem is over against hub 13, with spring 15 compressed. Treadle valve 41 is released with spring 44 extended. Check valve is closed with spring 37 extended. The triple valve is then in set position with a pressure behind the brake cylinder piston determined by the length of piston travel which would be lbs. when the cylinder piston is set at its normal length of travel which is inches.

When the arrangement of Fig. 3 is employed, the spring 15 being absent, the above operation would be modified as follows: Nith piston 16 over so that hub 15 is against hub 13, the point of latch 101 will be forced off from surface 107 onto surface 108. The treadle valve 41 would then be released and the balance of the operation the same as already described.

Position 3.As soon as an increase of train line pressure of 3 lbs. over Whatever the pressure may be in chamber 11 of cylinder 8, is made, the pressures in the two chambers 10 and 11 oi cylinder 8 are equalized at whatever pressure is in the train line 1 through the train line cross-over pipes, because in position 2 there remained a pressure of only lbs. in chamber 10 of cylinder 8. The different parts of the release valve will then be in the following position: Check valve 24T is open with springs 27 compressed, piston 16 in chamber 11 oi? cylinder 8; is over against the flange of piston stop 18 with spring 102 of the latch compressed. Latch 101 will assume its normal position with the point resting against plane 107 of contour oil the piston. Treadle valve 4:1. is closed and spring 14 is compressed. The compression of this spring, which represents three pounds, together with the air pressure in the chamber .31 which is at lbs. gives a total pressure of 56 lbs. on the top side of the atmosphere port lining valve On the check valveside of this atmosphereport lining valve there is a 5 pound spring 37, and pounds of air pressure irom chamber 31 immediately.

which makes a total of pounds, which gives 1 pound more down-thrust than there is rip-thrust. (The areas of the two sides 01 the atmosphere port lining valve, also area of check valve being all the same, the force in any given direction 01? the atmosphere port lining valve would be regulated by the difference in the strength of the two springs 44 and 37, respectively; however an area of 1 inch was contem plated.)

This forces check valve 35 of auxiliary reservoir 2 to open. allowing air to escape therefrom into no-npressure chamber 32 and out to the atmosphere through the side of port 46 oi lining valve 88. which is then aligned with the atn'iosphere port 29. This action immediately reduces the pressure on the check valve side of the atn'iosphere port lining valve to such an extent and so quickly that it causes the atmosphere port lining valve on piston 83 to be thrust farther downward by pressure in chamber 31, thereby opening ports 30---l-5,which releases air The triple valved is then in released position with auX- iliary charging.

No further movement of: the automatic valve parts will take place until a reduction in the train. line pipe and chamber 11 is made. The various parts of the automatic release valve are all then in position as described under position 1, and with the pre sure in auxiliary reservoir building up from 4-2 lbs.

In closing, the following general remarks should be noted: In the application of this device provision should be made for removal from car for cleaning and testing; also a pipe union should be interposed next to the T on the crossover pipe; alsoa dust c01lec tor of some design should be applied.

Since a. reduction of train pipe pressure of 20 pounds is necessary to. disturb this valve and cause it to function, it will be seen that whenever brakes do not release and this failure is caused by sluggish tripples when set with a reduction Of less tioned isestablished the valve will make the necessary reduction in auxiliary reservoir pressure. The workings of a triple valve are such that a slight reduction at the engineers valve causes the brakes to set, but not so tightly as when 20 poundsor more reduction is made, and especially when an emer ency reduction is made, the brakes Will be set very tightly. It will be seen then that in most cases it will not be necessary to provide an automatic release valve which would operate when slight or below 20 pounds reduction are made.

. What I claim is: i f 1. An air brake system, including a trai pipe, an auxiliary reservoir, abrakev piston cylinder, a triple valve. and a branch pipe extending from the train pipe to the triple valve and supplying air therethrough to said auxiliary reservoir and brake piston cylinder, said triple valve also controlling the release of air from said brake cylinder, in combination with an automatic release valve connected directly between said train pipe and said auxiliary reservoir, and comprising the following instrumentalities: a main cylinder containing two chambers each independently connected to the train pipe, a connection from said cylinder to the auxiliary reservoir, and means responsive to normal pres-sure in the train pipe to maintain a balanced condition of pressures in said chambers, said means then acting to permit feed through the triple valve for charging.

2. The air brake system described in claim 1, in which the connection from the release valve cylinder to the auxiliary reservoir is through a second cylinder communicating with the first, but normally, during charging, closed oil by valves from both said first cylinder and said auxiliary reservoir.

3. The air brake system described in claim 1, in which the connection from the first cylinder to the auxiliary reservoir is through an auxiliary cylinder containing a movable piston responsive to changes in pressures as between the first cylinder and the auxiliary cylinder, and controlling the valve connection to the auxiliary reservoir.

4:. The air brake system described in claim 1, in which a piston is provided between the two chambers of the release valve main cylinder, with a spring normally tending to close the same so as to disturb the balance of pressures in said chambers, thereby 1naintaining the release valve in an inoperative condition.

5. The air brake system described in claim 1 having a main cylinder divided into two chambers, an open connection from one chamber to the train pipe, a connection from the other chamber to the train pipe with an inwardly opening check valve therein, a channel with valves extending from said chambered cylinder to the auxiliary reservoir and a piston in one of the chambers of the main cylinder controlled entirely by changes of pressure in the train pipe, and itself acting to control the valves in said channel.

6. The air brake system described in claim 1 in which the release valve cylinder con tains two main chambers, as an auxiliary chamber connecting the same with the auxiliary reservoir at the brake system, means responsive to flow pressure in the train pipe to maintain pressures in the main chambers of the release valve balanced and the aux iliary chamber closed, and means responsive to a percentage reduction in the train pipe pressure to reduce the pressure in one chamber of the release valve cylinder while maintaining it in the other chamber and thereby to produce an opening of the auxiliary chamber and operation of the brake piston under pressure.

7. The air brake system described in claim 1 in which the release valve has two chambers as 10 -11, and an auxiliary chamher as 31, with connections from the first two chambers tothe train pipe and from the third chamber to the other chambers and to the brake cylinder ports, valves controlling the connections from the main chambers 10-11 to the auxiliary chamber 31, and from said auxiliary chamber to said brake piston ports, a check valve in the'main chamber 10, and equalizing means between the chambers 1011, all of said valves and said equalizing means being provided with mechanical pressure elements of predetermined strengths adapted to balance the air pressures desired to be produced for charging, application, and release, respectively.

8. An air brake system comprising a train pipe, an auxiliary reservoir and brake cylinder, and a triple valve, together with a branch pipe connection from the train pipe to said triple valve and the other parts controlled thereby, in combination with an automatic release valve comprising the following instrumentalities: means responsive to normal pressure in the train pipe to maintain the said automatic valve inoperative and permit normal operation of the other parts;

means responsive to a partial reduction of pressure in the train pipe to unbalance pres sures in said automatic valve and means controlled thereby to produce-a quick application of the brakes by immediate back release pressure in the brake piston cylinder.

9. The system described in claim 8 with means responsive to a fractional percentage of increase in the train pipe pressure after the reduction for application of the brakes is made, to equalize pressures in the automatic valve, and means to release air from the auxiliary reservoir for release of the brakes.

10. The system described in claim 8 with means responsive to a fractional percentage of increase in the train pipe pressure after the reduction for application of the brakes is made, to equalize pressures in the automatic valve, means to release air from the auxiliary reservoir for release of the brakes, and mechanical means differentially arranged with respect to the unbalanced air pressures between the main cylinder and the auxiliary reservoir, whereby the vent from the latter will be first opened and then closed, leaving the triple valve in release position, but with auxiliary reservoir charging.

11. An air brake system comprising a train pipe, an auxiliary reservoir and brake cylinder, and a triple valve, together with a branch pipe connection from the train pipe to said triple valve and the other parts controlled thereby, in combination with an automatic release valve comprising the following instrumentalities: a main cylinder receiving pressure from the train pipe and divided into two compartments normally separated by a spring pressed piston, an aux iliary cylinder connecting the main cylinder with the auxiliary reservoir, a port opening from the main cylinder into the auxiliary cylinder, a treadle valve closing said port and normally underlying said piston, means to unbalance pressure on opposite sides of said piston by a fractional reduction of pressure in the train pipe, the movement of the piston then uncovering the treadle valve, means responsive to changes in the balance of air pressures to effect the application and release of the brakes, means responsive to a relatively small fraction of increase in the train pipe pressure after application of the brakes, to release air from the auxiliary reservoir and release the brakes and thereafter to close the auxiliary reservoir, leaving the triple valve in release position with the auxiliary reservoir charging, and a latch for maintaining said piston in charging posi tion.

12. An air brake system comprising a train pipe, an auxiliary reservoir and a brake cylinder, a triple valve. together with a branch pipe connection from the train pipe to said triple valve and the parts controlled thereby,

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brakes by a small increase of air pressure in the train pipe, and to maintain the system with the triple valve in release position, With 10 auxiliary charging. a In testimony whereof I hereunto aflix my signature.

SAMUEL E. TURNER.

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