US953510A - Railway-car brake. - Google Patents

Description

L. BOIRAULT.

RAILWAY GAR BRAKE.

APPLICATION FILED JAN. 9, 1908. 9535 1 0, Patented Mar. 29, 1910.

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ANDREW a. GRAHAM co. PMOTO-LIYHDGRAFNERS. WASHINGTON, 2 c.

L; BOIRAULT.

RAILWAY UAR BRAKE.

APPLICATION FILED JAN. 9, 1908.

Patented M31129; 1910.

3 SHEETS-SHEET 2.

727%. WJW'O LOUIS BOIRAULT, OF PARIS, FRANCE.

RAILWAY-CAR BRAKE.

Specification of Letters Patent.

Application filed January 9, 1908.

To all whom it may concern:

Be it known that I, LoUIs BOIRAULT, a citizen of the Republic of France, resldmg at 8 Rue Emile-Gilbert, Paris, in the RepubllC of France, engineer, have invented certain new and useful Improvements in Railway-Car Brakes, of which the following is a specification.

Hy invention relates to improvements in i; railway car brakes and has for its object to provide a brake having friction blocks so arranged as to be applied to the rim of the wheels and connected with a system of op erating levers.

The invention consists in making use of the live force of the car to produce the application of the brake in such a manner that when the system of operatmg levers has been brou ht either d1rectl b hand or throu 'h I r the action of any suitable gearing, into a man or by a source of compressed air.

Two embodiments of the improved brake are shown in the accompanying drawing in which:

Figure 1 is a vertical section of the braking mechanism, in a position in which it is ready to be operated by the cam mounted on the axle; Fig. 2 is a plan view corresponding to Fig. 1. Figs. 3 to 5 are diagrams showing different positions of the braking mechanism. Figs. 6 and 7 show diagrammatically gearing whereby the brake may be controlled from the brakemans seat. Fig. 8 is an elevation of a second embodiment of the brake, shown in the closed position or on. Fig. 9 is a vertical section on the line 99 of Fig. 8. Fig. 10 shows certain members of the said brake in the open position or off.

Under the truck frame of the car, shown in dotted lines in Figs. 1 and 2, is supported in bearings a shaft 1 carrying the arms 2, to which are pivoted the rods 3 provided with the brake-blocks 4; the latter so arranged as to be applied to or on the rim of the wheels 5, are connected to the rods 3 through the medium of springs 6, interposed between the bottoms of the brake-blocks and bearing plates 7 embedded in the conical ends of the rods 3; the said bearing plates are guided by pins 8 in slots provided in the cheeks 9 of the brake-blocks. The shaft 1 carries also an operating arm 10 and a locking arm 11.

The arm 10 is connected by a link 12 to a lever 13 located in front of a cam or eccentric 14 which is fixedly attached to the axle 15 or to a wheel 5. The upper end of the lever 13 is hung at 16 to a lever 17 so as to permit it to be raised or lowered, while being at the same time brought back or forward with respect to the axle 15. For that purpose, the opposite end of the lever 17 is provided with a pin 18 engaged in a race 19 which is rigidly secured to the truck-frame of the car, and an intermediate point 20 of the lever 17 is connected by a link 21 to another pin 22, also engaged in the race 19. The length of the link is preferably equal to that of the part 18-20 of the lever 17, so that if the pins 18 and 22 are moved in the race 19 symmetrically with respect to a shaft 23, the point 20 will be caused to move in a line perpendicular to the race and passing through the said shaft, and the end 16 will describe a curved line 24.

To get the symmetrical displacement of the pins 18 and 22, there are secured to the shaft 23 two cams 25 provided with races 2630 in which are engaged the ends of the pins 18 and 22; the shaft 23 may be made to swing by means of two levers 31 loaded with balance-weights 32 and secured to its ends, whereby the brake may be controlled equally well from either side of the car.

The locking of the brake-blocks in the position in which they are applied to the rims of the wheels is obtained by means of a slide 33, provided within a longitudinal groove and guided both by the projections 34: of the race 19 and the shaft 23 which passes through the said groove; the lower end of the said slide is so arranged as to lie above the arm 11 (see Figs. 1, 3 and 1) so long as the brake is not applied, and to fall down behind the said arm (see Fig. 5) as soon as the brake is applied, thus preventing it from moving backward. In the groove of the slide are also engaged the pins 18 and 22, and the length of the said groove is so determined that the pin 22 carries the slide upward when the system of levers is brought back to its position of rest (see Fig. 3), I whereby the arm 11 is relieved. The brake also comprises a hanger link 35, preferably adjustable, to support each brake-block 4 at the proper height under the truck-frame of the car, as well as a spring or balanceweight device (not shown) for moving the brake-blocks away from the wheels upon being loosened.

The operation is as follows: In the position of rest (see Fig. 3) the levers 31 are nearly horizontal and by the action of their balance-weights the cams 25 are securely held in the posit-ion in which the pins 18 and 22 rest in the end 26 of the races and are removed the farthest from each other. The lever 13 is then raised and removed away fromthe axle 15, so that the cam 14 revolves without touching it. The brakeblocks are removed away from the wheels and the slide 33 is raised above the arm 11. hen the brake-blocks are to be applied or closed on the wheels, the shaft 23 is caused to revolve in the direction shown by the arrow in Fig. 1 until it is brought to a stop. During the first part of its rotation, the pins 18, 22 remain in the concentric parts 27 and 27 of the races of the cams 25 and the lever 13 remains stationary, then when the levers 31 have moved past the vertical position, the parts 28 and 28 bring the pins 18 and 22 toward the shaft 23 and cause the point 16 to move down the curve 24. \Vhen the points 28 and 28 of the cams come in contact with the pins 18, 22, the lever 13 comes into such a position (see Fig. 4) that it can bear against the cam 14 if the latter is revolved toward it. The levers 31 are then sufficiently removed from the vertical to prevent them from being brought accidentally back by jarring to their position of rest; they may therefore be left in that position (see Fig. 4) if the intervening cam 14 prevents them from being moved farther down at once. If the cam 14 is at that moment turned in another direction, the levers 31 can be moved downward into the position shown in Fig. 1, when the pins 18, 22 are brought nearest together by the parts 29 and 29 of the cams 25. The rotation of the shaft 23 is then stopped by a spur 36 integral with the latter and by a pin 37 integral with the slide 33 (see Figs. 1 and 2.)

On account of the rotation of the cam 14, the lever 13 is pushed back and made to swing around the stud 16, causing the shaft 1 to rock with the arms 2 and the arm 11. The brake-blocks are thus pressed onto the wheels by a pressure which is gradual and limited on account of the springs 6. The arm 11 is moved away and allows the slide 33 to fall, so that after the cam 14 has passed the said arm cannot move backward and thus holds the brake-blocks locked in the braking position. (See Fig. 5.) 011 the other hand, on account of the fall of the slide 33, the pin 37 allows the spur 36 to pass, and the shaft 23 continues to revolve under the action of the balance-weights 32; so that the parts 29 and 29 of the cams 25 move the pins 18 and away from each other to a certain extent; the lever 13 is thus raised and removed from the path of the cam 14, not to be impinged upon and subjected to wear at each revolution of the wheel. (See Fig. hen the brakeblocks are being applied or closed on the wheel, the lever 13 pushes the lever 17 to some extent, so that the pins 18 and 22 have tendency to move away from each other, but they bear on the parts 29 and 29 of the races or slots which are normal to the radii (dead points) and, on that account, are sure to remain stationary. The reaction due to the closing of the brake-blocks cannot therefore, produce any accidental return of the system to its position of rest. Vhen it is desired to stop the braking action, the rock shaft 23 is moved backward by operating one of the levers 31; the cam slots move the pins 18, 22 first toward and then away from each other; in its upward stroke the pin raises the slide 33 and moves it away from the arm 11; the brake-blocks are loosened in'imediately and the arm again comes un-- cler the slide. Finally, all the parts of the mechanism again come into the positions shown in Fig. 3.

Instead of operating the shaft 23 by means of the hand levers 31, the said shaft may also be operated from the brakemans seat 37 (see Fig. (5) through the medium of a lever 38, of the gear wheels 39, 40, 41, 42, and of the chain and wire belts 43 and 44; in this case, the hand levers 31 may be located on the shaft of the idle wheels 40, 41, as shown in dotted lines in Fig. 6. According to Fig. 7, the shaft 23 is controlled or operated from the brakemans seat through the medium of a lever 38, of gear wheels 39 and 42, and of belting 43, 44 passing over rollers Anyhow, the brake can be controlled or operated either from the ground or from the seat. The cams 25, can also be operated by means of controlling devices actuated by compressed air or by a vacuum, similar to those now in use for continuous brakes. In this case, the present system of braking has the advantage of requiring smaller air cylinders and of consuming a much smaller amount of air.

It is to be understood that, without departing from my invention, the whole of the braking mechanism employed to bring the lever 13 and the cam 14 together or to move them away from each other may be replaced by any other equivalent or similar braking mechanism. Likewise, the locking device may be replaced by a pawl, bolt, or stop arranged in any suitable manner. For in- 3 Y stance, the i'nechamsm shown in F igs. 8 to 10 comprises a shaft 1 supported by the frame of the car and carrying the arms 2 to press the brake shoes 45 against the wheels through the medium of the springs as in the former case. The frame also supports a shaft 23 on which is mounted av cam 25; the latter acts on a spindle 18 slidable in slide-ways provided in two brackets 19, secured to the frame. On the said spindle is secured a bifurcated rod 17, pivoted to a lever 13, which is arranged in front of or opposite a cam 14. on the axle 15; the said lever is also connected by a link 12 to an arm 1O integral with the shaft 1. The said shaft 1 carries also an arm 11 to which is pivoted a pawl 11 arranged to impinge, by means of stepped projections 11, against a slide 33. The latter is slid ably mounted on the hub of the cam 25 and on a fixed stud 31; it has a projection 33" so arranged as to be moved upward by a cam 22 secured to the shaft 23; its lower part also carriesa projection 37 so arranged as to be moved downward by a face 36 of the said cam 22.

The am is loosely mounted on the shaft 23, but its hub carries a projection 25 engaged with some amount of play (about 30) in a slot of the hub of the cam 22, which is rigidly secured to the shaft 23. The said shaft may be operated by any suitable means, as for instance the shaft 23 of the en'ibodiment hereinbefore described. On the shaft 23 being revolved or turned so as to bring the cams and 22 into the position shown in Fig. 10, the brake is opened or moved off the cam 11' then passes in front of the lever 13 without producing any effeet. If the shaft 23 is turned in the direction of the arrow shown in Fig. 10, the cam 25 is carried forward and pushes back the spindle 18, so that the rod 17 moves the lever 13 toward the cam 1 t. The con- .tour of the cam 25 is so determined that the operation cannot be reversed, that is, the pressure of the spindle 18 on the cam 25 cannot cause the latter to turn backward. The result is that the cam 1%, which turns or revolves when the car is moved in either direction, pushes back the lever 13 and thereupon the link 12 causes the shaft 1 to rock so as to press the shoes & against the wheels 5; at the same time the pawl 11 is moved forward so as to enable the projection 33 of the slide to move down behind the projections 11, preventing the brake from moving off the wheels on the cam 1 t no longer acting on the lever 13. Beyond the part of the cam 25 which has the greater radius, the contour is lower and lower from 29 to 30, in order to enable the lever 13 to move slightly away from the cam 14: on the brake being moved down onto the wheels and locked in place thereon.

The shape of the cam 22 and the angle of play of the cam 25 with respect to the cam 22, are so determined that on the brake being moved on, the slide 33 is en-' abled to move downward before the portion 29 of the cam 25 which has the larger radius can act on the spindle 1c, whereas on the brake being moved off, the cam moves the slide 33 upward to release the pawl 11 before the cam 25 allows the rod 17 to move backward. Furthermore, the face 36 is so determined, as to impinge against the projection 37 and to not allow the swinging of the shaft 23 and of the cam 25 in the direction to close the brake, until the slide 33 has been enabled to move downward, that is, until the pawl 11 has been pushed back by the action of the cam 14:. On this action being produced, the slide 33 is enabled to fall at once by its own weight or gravitation to retain the pawl; in case even that it should be interfered with by some resistance or other, its downward movement is assisted by the pressure of the cam 22 on the projection 37, so that it moves either at once or on the cam 14 making another revolution. Again, the pin 36 then prevents the slide from being moved up through jarring and from releasing the pawl, before the shaft 23 and the corresponding cams are revolved or turned in the direction to move the brake off. In this embodiment, the lever 13 is provided with a plurality of rollers 13 which are subjected to the action of the cam 14:, for the purpose of reducing friction and preventing the resistance from causing a stoppage and thus cause the wheels 5 to slide on the rails.

Claims:

1. In a car, the combination of an axle having wheels, a cam on the said axle, shoes adapted to brake the wheels, a cam lever adapted to be engaged by the cam and connected to the shoes, a locking arm connected to the shoes, a slide adapted to engage the locking arm, a driving shaft, cams on the said shaft, means actuated by the said cams whereby the lever is brought into or moved away from the path of the axle cam, a projection on the shaft, and a projection on the slide, the said cams having dead points, and the slide projection being so located as to engage the projection'of the driving shaft and stop the rotation of the latter at the position in which the dead points of the cams actuate the said means whereby the said lever is moved as described.

2. In a car, the combination of an axle and wheels, a cam on the axle, brake-blocks adapted to brake the wheels, a lever connected with the blocks, operative means adapted to bring the said lever into or out of the path of the said cam, locking means to maintain the brake-blocks closed, the said means being adapted to automatically lock the brake-blocks as soon as they are closed and to hold them closed independently of the cam on the axle, and a connection between the operative means and the locking means, whereby the locking means relieve the brake-blocks when the operative means are brought into a position to move the said lever away from the cam on the axle.

3. In a car, the combination of an axle and wheels, a cam on the axle, brake-blocks adapted to brake the wheels, a lever adapted to the shaft, arms 011 the said shaft, links 7 connecting the said arms with the brakeblocks and with the said lever respectively, operative means to bring the said lever into and out of the path of the said cam, another arm on the shaft and a bolt adapted to en gage the last mentioned arm and connected to the operative means, substantially as described.

4. In a car, the combination of an axle and wheels, a cam on the axle, brake-blocks adapted to brake the wheels, a cam lever adapted to be engaged by the cam and connected with the brake-blocks, a slide-way, levers having their ends guided in the said slide-way, the cam lever being pivoted to one of the said levers, a shaft passing through the slide-way, grooved cams on the said shaft adapted to move the said ends of the levers in the slide-way or race, and 0perative means to swing the said shaft, substantially as described.

5. In a car, the combination of an axle and wheels, of a cam on the said axle, brake-blocks adapted to close onto the wheels through the action of the cam, looking means to maintain the brake-blocks closed, the said means being adapted to automatically lock the brake-blocks as soon as they are closed onto the wheels and hold them closed independently of the cam, and springs interposed between the said brakeblocks and the locking means, substantially as described.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

LOUIS BOIRAULT. WVitnesses:

DEAN B. MASON, MAURICE RoUx.

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