US657669A - Air-brake. - Google Patents

Description

No. 657,669. Patented Sept ll, I900. J. J. NEF.

AIB BRAKE.

(Application filed June 22, 1898 No Model.) 5Sheeis'-She8f 1.

WITNESSES:

m: mums PETERS co, wom umo, wnsmnmow n, c.

Patented Sept. u, I900.

J. J. NEF.

AIR BRAKE.

(Application filed June 22, 1898.

Modem 5 Sheets-Sheet z,

ATTORNEY WITNESSES: 6 lNVENTOR m: Nonms warns c0, purmmurnou WASHINGTON n. c.

Patented Sept. n, 1900.

J. J. NEF.

AIR 8 R A K E.

(Application filed June 22, 1898.)

5 Sheets Sheet 3.

(No Model.)

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.75 WITNESSES:

ATTOR N EY Patented Sept. 6,1900.

J. J. NEF.

AIR BRAKE.

(Application filed June 22, 1898.)

5 Sheets$heet 4,

(No Model.)

WITNESSES! MVMM THE mums PETERS co. PHnYO-LITHD.'WA$MINGTON. n. c.

No. 657,669. Patented Sept. ll, I900. J. J. NEF.-

AIR BRAKE.

(Applic ation filed June 22, 1898.)

5 Sheets Sheet 5.

lgjSSES: h??? BY m: cams Pn zns co. mow-Own. WASHINGTON. n, c.

UNrrED STATES PATENT (j-FU Jot-IN .iA'oon NEF, or NEW YORK, iv. v.

AlR-BRAK E;

SPECIFICATION forming part of Letters Patent No. 657,669, dated September 11', 1900.

Application filed June 22,1898- Serial No. 684,160. (No model.)

To all 1071,0772 it 772,0 7] concern.-

Be itknown that 1, JOHN JACOB NEF, acitizen of the United States of America, and a resident of the city, county, and State of New York, have invented certain new and useful Improvements in Air-Brakes,of which the following is a specification.

Hy invention relates to pumps and pumpoperating mechanism for air-brakes and to automatic governing devices for controlling same; and my invention consists more particularly in an improved form of frictionclutch controlled by the governor to throw the pump in and out of operation, in improvements in details of construction of the pump and its connections, and in an improved form of governor.

The objects of my invention are to simplify the construction of the parts, to render the working parts accessible for repairs, to condense the working parts and to reduce the space occupied thereby, and to so construct the clutch that it shall instantly free itself when the pressure is removed, thus providing against the objectionable jamming of jaw or cone clutches, as used heretofore; and my invention further consists in certain novel details of construction and arrangement and combination of parts, as will hereinafter be more fully described.

I will now proceed to describe my invention with reference to the accompanying drawings. and will then point out the novel featnresin claims.

Figure l is a general view of an air-brake system, showing the pump and pumpoperating mechanism, the governor, service-valve, jam-cylinder, and the tank in which the supply of compressed fluid is stored. Fig. 2 is a central horizontal section through the pump and pump-operating mechanism and certain other parts attached thereto. Fig. 3 is a vertical cross-section on the plane of the line 3 3 of Fig. 2. Fig. 4 is a vertical longitudinal section taken on the plane of the line 4 4: of Fig. 2 and looking in the direction of the arrows. Fig. 5 is an end View of the pump, pump-operating mechanism, and governor, with a portion of the pump broken away to show the valves therein. Fig. 6 is a vertical cross-section taken on the line 6 6, Fig. 2,410 show the clutch mechanism and its operating car-wheel, 8 designates the car-wheel axle,

upon which is mounted a gear-wheel, and through which the pump is driven, as hereinafter to be fully set forth. 9 designates the gear-casing surrounding the said gear and axle and supporting the clutch box or casing 10. 11designatesthepump;12,thegovernor; 13,the service-valve;14, the jam-cylinder, and 15 the compressed-fluid reservoir.

Referring now more particularly to the other figures,which show the parts in section, 16 designates the gear-wheel, which for purposes of attachment is made in two sections. It is preferably secured to the axle by means of a pin 17, which is set half-way into a hole drilled in the axle to receive it and half-way into one section of the gear-Wheel and the two sections then clamped together by means of clamping bolts and nuts 18. The casing 9,which surrounds the gear-wheel 16, is composed of a cap portion 9 and an extension 10 of the casing 10,which incloses the clutch mechanism. The parts 9 and 10 are bolted together by suitable bolts, as shown.

19 is a bushing lined with antifriction metal, such as Babbitt metal,and-made in two halves, the junction, however, not being coincident with thejunction of the parts 9 and 10.

Numeral 20 designates the pump-shaft. This shaft has three bearings or points of support-two in the casing 10 and the third in the side of the pump-cylinder. The intermediate bearing,which is in the casing 10, is of ordinary construction and is provided, as usual,with an antifriction-m'etal lining. The end bearing is carried by the pump and is designated by the numeral 21. It forms also a cap for the end of the shaft to exclude dust and to retain the oil or other lubricant. The third bearing is a double bearing of special construction.

22 is a collar fitted loosely upon the shaft 20, but secured to the hub 23 of a gear-Wheel 24. The gear-wheel 24 meshes with the gearwheel 16 and is rotated thereby.

25 designates a hub in the casing 10,which is provided with an antifriction-metal lining or sleeve 26, secured thereto.

The hub 23 of the gear-wheel 24 is provided with a retaining-nut 27 to prevent longitudinal movement of same.

28 is a longitudinal thrust-bearing for the shaft 20 and is suitably secured to the casing 10. It may, if desired, be provided with ballbearings 29, as shown.

The gear-wheel 24 is provided with two keys or projections 30 on the inside of its rim, which keys or projections engage with notches 31 in a series of disks 31, one of which is shown in detail in Fig. 7. The disks 31 are so arranged that they will always turn with the gear 24.

32 designatesa series of disks arranged alternately with the disks 31, but which are of smaller diameter than the said disks 31. They are provided centrally with a square perforation 33,. (see detail Fig. 7 which is adapted to loosely fit a squared portion 20 of the shaft 20.- Thus the disks 32 are arranged to always turn with the shaft 20. The disks 31 have a central orifice 34 of such size that they may turn independently of the shaft 20.

35 designates afollower fitted in the samemanner as the disks 32 with a square perforation,and hence adapted, like the said disks, to turn with the shaft 20.

36 is a ring fitted into a groove in the hub of the follower and provided with pins 37, engaging with slots in a yoke 38 in a manner well known, so that the follower can turn with the shaft, but still be free to' be moved 1 longitudinally upon the same by the yoke 38.

39 designates the pump-cylinder, provided with cylinder-heads 40,- closing the ends there'- of. The cylinder is suitably secured tothe casing 10 by bolts.

Figs. 2, 3, and 5 show more fully the details its ends, and a similar port at the opposite end communicates with a similar valve and valve-chamber, and both connect witha common discharge-outlet 44, adapted to receive a pipe 45, connected with the air-reser- 46 designates a suction-valveengaging voir. with a valve-seat in the bushing 47. There are two of these valves, one for each end of the pump-cylinder, and on their intake side they communicate with a common inlet-passage 48, preferably closed by a wire screen to protect from dust. The valveson their other sides communicate with the interior of the pump-cylinder, and through these valves 46 air is taken into the pump to be discharged through the discharge or check valves 41' into the air-reservoir 15. 49 designates the pump-piston, having two heads or bearingsurfaces 49 49*, provided with packing-rings. Intermediate of the two heads 49' 49, which are connected together by webs 49 49*, there is provided a guideway to receive the bearing-pieces 50. The shaft 20is provided with a crank 51, preferably formed by bending the shaft at this point, and this cranked or bent portion engages with the bearing-pieces 50. The bearing-pieces reciprocate transversely of the cylinder in the guideways. Thus a ro- 3 tation of the shaft 20 causes reciprocation of jthe pump-piston. A set-screw 52 passes through the lower side of the pump-cylinder l and engages with a slot in the piston. The lset-screw fulfils the double function of pre- 1 venting the piston from rotating in the cylinl der and when removed permits the accumu- 1 lated oilor other lubricant or any fluid which may have collected from any cause whatever to be drawn off and drained away. .53 is a vent to permit the escape of gases or oil-vaipors which may have formed within the cas- Tings, the said casings being otherwise entirely inclosed from the outside atmosphere in order to exclude dust and to permit the :casings, if desired, to be filled with oil or 5 other lubricant and to prevent same from es- ;cape. The vent is preferably covered with :wire-gauze. A series of channels or orifices, fsuch as 54 55, permit a circulation of the luj brican t from one chamber to another.

Numeral 12, as before stated, designates the governor as a whole. It is best shown in detail in Figs. 2 and 4. Broadly speaking, it 1 consists of two partsa compound cylinder 56 and a valve-chamber 57. The compound cylfinder has a larger bore 58 and asmaller bore v59. Suitable pistons fit the two portions 58 and 59 and are connected together by a bar for rod 60. The larger end 58 of the cylinder 56 is closed by a head 61 and the smaller portion by a head 62, forming also a spring-easing and which contains the spring 63. The connecting rod or bar of the compound piston engages with-the end of the before-mentioned yoke-rod 38'. Thus a movement of the compound pistonin one direction will throw the clutch into engagement and in the other direction will throw the clutch out of engagement. This arrangement of compound cylinder'and piston heads with clutch-lever and yoke avoids the use of stuffing-boxes, which are exceedingly undesirable in such mechanism owing'to their needing constant attention to keep" tight and their liability to become packed too tight and to jam the parts. The valve-chamber 57 is provided with a cylindrical portion 64, in which is arranged a piston ,65. The piston 65 carries a hollow stem 66, .which engages with a coiled spring 67, bearing at its other end against an adjusting-nut IIO 68 and resting on a stem carried by the said adjusting-nut. (59 is a slide-valve adapted to slide on a valve-seat or slideway 70. 71 is a port which affords communication between the valve-chamber and the interior of the larger end of the com pound cylinder, and 72 is a port which afiords com m unication between the valve-chamber and the smaller end of the compound cylinder. 73 is a port communicating with the atmosphere. The smaller end of the compound cylinder is always in communication with the air-reservoir through the pipe 74:, which for convenience is shown as a branch of the pump discharge-pipe45. Hencetheairpassingthrough the port 72 is always in communication with the valve-chamber. position, as shown in the drawings, (see more particularly Fig. 4,) the slide-valve 69 uncovers the port 71. The air passing through into the larger end of the compound cylinder forces the compound piston over to the right, as shown, against the pressure exerted by the smaller end of the piston and against the pressure of the spring (33, the said spring not being sufficient to overbalance the difference of areas of the piston-heads constituting the compound piston. The clutch is thus thrown out of engagement. When,however,the valve is caused to move to the left the air-supplyis cut off from the larger side of'the compound cylinder and the air that is already contained therein exhausted through the port 73. The entire force of air is now exerted on the smaller side ofthe compound piston to force the clutch into operative position.

Referringnow more particularly to Fig. 5, it will be seen that the suction-valve casing is provided below the suction-valve with a cylindrical portion in which is fitted a plunger or piston 75. Below the two casings and connecting them is a hollow casting 76, having an opening 77 into each cylindrical portion below the piston therein, and an internally-screw-threaded extension 78 is adapted to receive one end of a pipe 79, which pipe connects with the exhaust side of the servicevalve 13, as shown. A branch 80 from this pipe connects with the spring-actuated side of the cylindrical portion 64 of the valvechamber 57. Thus the reservoir will always require to be replenished after air has been used for setting the brakes the releasing of the brakes and causing the exhaustair to operate on this side of the governor will at once start the pump. 81 is a connection between the service-valve and the jamcylinder.

Figure 8 represents the particular form of service-valve preferably employed and which forms the subjectanatter of a separate application iiled by me June 22, 1898, Serial No. 684,159. It is therefore not described herein in detail. Snffice it to say that when the valve 82 is moved in one direction it uncovers the port 83 in communication with the pipe 81, opening said pipe to the interior of WVhen the parts are in the valve-chamber, which is in open communication with the reservoir. When the valve is moved in the other direction and is in position as shown in Fig. 8 of the drawings, the port 83 is closed to the interior of the valve chamber, but is open through the valve to the pipe 79.,

The mod us opercmdz' is as follows: The axle 8 is revolved by the motion of the car. This rotates the gear 16, which is fast upon it, and in turn the gear-2a is revolved. Thus the gear which carries one member of the clutch in the disks 31 is always revolving while the car is in motion. l/Vith the other parts in position as shown in the drawings, which is their normal position, the pumpshaft 20 is at rest and the pump out of op eration. The supply of air in the reservoir is complete and at a predetermined pressure. To apply the brakes, the service-valve is operated in the usual way, and air passes through the pipe 81 into the jam-cylinder 1e. WVhen the car is started and the brakes released, the exhaust from the jam-cylinder will return through the pipe 81 and down the pipe 79 through the branch 80. The pressure in the air-reservoir will by reason of the removal of some of the air be reduced. The spring 67 in the valve-chamber 57 of the governor having been set to exactly balance the required pressure will now overbalauce the pressure in said chamber and will cause the slide-valve 69 to slide to the left. This will close the supply of air to the larger portion of the compound cylinder and exhaust what pressure there is therein contained through the exhaust-port 73. The air-pressure on the opposite side in the smaller portion of the compound cylinder, aided by the spring 63, will force the compound piston over and carrying with it the end of the yoke 38 will cause the follower to bring into frictional engagement the member of the clutch carried by the pumpshaft-mamely, the disks 81. The end thrust will be taken up by the thrust-bearing 2S and when used by the ballbearings 29. The frictional engagement of the two members of the clutch will cause to tation of the pumpshaft and a consequent operation of the pump to restore the air to the reservoir. It is not, however, desirable to start pumping immediately upon the starting up of the car, but rather to wait until the inertia has been overcome and the car ac quired its full momentum in order not to add resistance at a time when the most power is required foranother purpose. Furthermore, Wear upon the connecting parts is largely avoided, which would otherwise occur should the pump commence to operate and force air into the reservoir against a high pressure beforethe connectingparts arefirmlysetagainst each other. The temporary throwing out of service of the pump is effected by the exhaust from the jam-cylinder,wl1ich,as before stated, passing down the pipe 79 into the casting 76, lifts the pl ungers or pistons 75, which in turn IIO 4 sewer;

lift the suction-valves 46. The plungers or pistons 75 do not fit their respective cylinders very closely, and the air gradually leaks by until the pistons drop of their own weight, the suction-valves return to their seats, and the pump operates. It is of course understood that during all this time the pumpshaft has been rotating and the pump-piston reciprocating; but while the suction-valves were held open the air simply passed in and out freely and no air was pumped into the reservoir. The air passing through the branch pipe 80 is intended to assist the spring 67 in first starting the piston and valve 69 (over) in case they should have become set or stuck. The pump will now continue to pump air into the reservoir until the pressure therein overbalances the spring 67 and the piston and valve resume their normal positions, ad mitting air to the larger portion of the compound cylinder and releasing the clutch. The clutch by reason of its construction cannot possibly jam or bind once the pressure is relieved. Hence the parts will instantly stop until the pressure of air is again lowered in the reservolr.

The pneumatic packing for the piston 65 and the compound piston in the compound cylinder 56 is preferably in the form of a cupped leather washer 82, carried by the piston-head, the said head having a hollow chamber 83 and orifices 84, aflording communication between the said hollow chamber and the chamber in which there is compressed air in one case the valve-chamber 57 and in the other the compound cylinder. The air-pressure will thus at all times force the leather out against the side of the cylinder and will insure a tight fit.

The spring 63 will cause the compound piston to move over to engage the clutch members at such times as there may be no air at all in the reservoir. Without this spring and without air in the reservoir there would be no way of starting the pump initially.

What I claim is 1. In an air-brake system, the combination with an air-reservoir of a pump and pumpoperating mechanism, an automatic governor pump-operating mechanism, and a clutch-1e ver operated by a connection between the piston-heads.

2. In an air-brake system, the combination with an air-reservoir of a pump and pumpoperating mechanism, an automatic governor comprising a compound cylinder having piston-heads of different diameters corresponding with the bores of the cylinder, an open, and at all times unobstructed, communication between the air-reservoir and the small bore of the compound cylinder, means whereby thelarge bore of the cylinder may be placed in communication with the air-reservoir, or with an exhaust, a clutch adapted to connect and disconnect the pump and pump-operating mechanism, and a clutch-lever operated by a connection between the piston-heads.

3. In an air-brake system, the combination with an air-reservoir of a pump and pumpoperating mechanism, an automatic governor comprising a compound cylinder having piston-heads of different diameters corresponding with the bores of the cylinder, means whereby a fluid-pressure is constantly maintained in the small bore of the compound cylinder, an auxiliary spring contained therein, means for varying the pressure in the large bore of the compound cylinder, a clutch-lever adapted to connect and disconnect the pump and pump-operating mechanism,and a clutchlever operated by a connection between thepiston-heads.

4:. In an air-brake system the combination with an air-reservoir of a pump and pumpoperating mechanism, the shell or cylinder of said pump comprising a casting having the two discharge-valve casings and the two suction-valve casings integral therewith the two discharge-valves each discharging into a common passage having a single connection with a pipe leading to the reservoir, the two suctionvalves having a common suction-inlet, and each having a cylindrical portion below the said valve in which is mounted a plunger or piston, and a hollow cap or facing connecting the two cylindrical portions, and having a single outlet connecting with a pipe to a source of compressed-air supply, and an automatic governor for connecting and disconnecting the pump and the pump-operating mechanism substantially as specified.

Signed by me at New York, N. Y., this 7th day of May, 1898.

JOHN JACOB NEF. Witnesses:

D. H. BATES, J r., J. O. OHAPIN.

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