US661345A - Automatic car-brake. - Google Patents

Description

Patanted Nov. 6,1900; B. S. 'LAWSUIL AUTOMATIC CAB BRAKE.

(Application filed. Feb. 20, 1900.)

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m. M5345. Patehted Nov; 6, I900; B. s. LAWSON.

AUTOMATIC CAB BRAKE.

(Application filed Feb. 20, 1900.)

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Patented Nuv. '6, I900.

No. 66L345.

B. S. LAWSON. AU'TOMATlC CAB BRAKE.

(Application filed Feb. 20, 1900.)

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(No Model.)

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MM T i l lfi BENJAMIN S. LA\VSON, OF NEW YORK, N. Y., ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, OF ONE-HALF TO DAVID W. COPELAND AND HENRY J. HART, OF SYRACUSE, NE\V YORK.

AUTOMATlC CAR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 661,345, dated November 6, 1900.

Application filed February 20, 1900. Serial No. 5,869. (No model.)

To all whom it may-concern.-

Be it known that I, BENJAMIN S. LAWSON, a citizen of the United States, residing in the borough of Brooklyn, in the city and State of New York, have invented a certain new and useful lmprovementin Self-Acting Brakes for Railroad-Cars; and I do hereby declare that the following is a full, clear, and exact description thereof.

The improvement applies to that class of brakes in which a piston is caused to move in a cylinder by the pressure of a fluid and acting through connected mechanism puts on and lets off the brakes. I can operate with air, but prefer a liquid, and will describe the invention as operating with oil. I operate a pump by the rotation of one of the axles, con necting the pump-frame to the same axle, so that it will partake of the same rising and sinking motions. The pump may work constantly; but in the most complete form of the invention such does not take place, because the valves do not operate, the piston being allowed to play idly in the pump-cylinder and the oil moving freely with it, while the induction-valves and the delivery-valves all rest undisturbed upon their respective seats. A single easily-moved valve controlled by the attendant determines whether this idle condition or the fully-workin g condition shall obtain.

The following is a description of What I consider the best means of carrying out the invention.

The accompanying drawings form a part of this specification.

Figure 1 is a longitudinal vertical section through the novel parts on the line 1 l in Fig. 2, some of the other portions of the car being seen in elevation. The wheels are in dotted outline. Fig. 2 is a plan View. The remaining figures are on a larger scale. Fig. 3 is a side elevation with certain portions in vertical section. Fig. 4 is a corresponding plan view. Fig. 5 is an end elevation as seen from the right in Fig. 3. A portion is sectioned on the line i 4 in Fig. 3, seen from the right. Fig. 6 is a horizontal section on the line 6 6 in Figs. 3 and 5. Figs. '7, 8, 9, and 10 are sections on the lines correspondingly numberedin Fig. 6. Fig. 7 is a longitudinalsection on the line 7 '7. Fig. 8 is a corresponding section on the central line 8 8. Fig. i) is a corresponding section on the line 9 Fig. 10 is a transverse vertical section on the line 10 10. Fig. 11 is a corresponding section on the line 11 11.

Similar letters of reference indicate like parts in all the figures where they appear.

A is the truck-frame, having the body of a car supported thereon by springs. (Not shown.) The attendant COIlll'OlS the brakes through either of the upright shafts mounted in the ordinary positions and turned, held, and released in the ordinary manner at will.

B are the ordinary carrying-wheels, set on axles B B, running in axle-boxes carried in jaws A in the truck, with liberty to rise and sink, subject to springs, (not shown,) all in the ordinary and long-approved manner.

N is an upright shaft operated by the brakeman standing on the platform through an ordinary hand-wheel. (Not shown.)

N is an ordinary chain operated by turning the shaft.

N are rods which form practically continuations of the brake-chain.

C is a pump-frame made in separable parts embracing one of the axles B and carrying slideways C, usually termed slides, and a nicely-bored pump-cylinder 0 having two ports 0 and 0 leading upward from the ends.

D is the induction-valve, and E the delivery-valve serving the port 0. Assuming the car to be moving from left to right, these will be at the rear end of the pump. Corresponding valves D and E serve the port 0 at the forward end of the pump. These valves rise and sink and perform their usual functions when required to apply the brakes, but during the greater portion of the time-all the time when the car is running freely along the track-the valves are idle.

C is my brake-cylinder cast in one with the frame C. It is closed at one end, the right, as shown; but the other end, the left, has only a partial head of annular form, the large central opening having a stuffing-box matching on a tubular or trunk extension M from a larger piston M, arranged to Work in the ordinary tigh t-fitting manner in the brak ecylinder C There is a port 0 leading upward from the right end of this cylinder. When oil is forced down through this port 0 it urges the piston M to the left, and this, acting through the stout rod 0, operates the brake-beams P,connected by rods and levers, as usual, and presses the brake blocks P strongly upon the wheels B and rapidly arrests the motion of the car. The brakes may be applied with all the force due to the strong action of the pump and released again by a simple and easy movement.

0 is what may be termed a controllingcylinder, cast with or fixed rigidly to the frame 0, closed at each end. Its inner surface is bored truly cylind rical,except for three circular channels or zones f, f and f communicating, the left one f with the left port a and the right one f with the right P011102. The duty of the middle zone f may be neglected for the present. Let us study the effect of the other zones and the sliding rings, which are slightly wider.

Then the operator turns the brake-shaft at either end of the car, he acts through a belt or pitch-chain and lever to move the rod I lying in the axis of the brake-cylinder and has to carry two rings I and I fixed on such rod. Turning the brake-shaft in the proper direction to release the brakes of an ordinary hand-operated system moves the rod I and the rings I and I to the right, so that the rings uncover the zones and allow any oil rising through the port 0 to flow freely upward and inward through the zonef' into and along in the controlling-cylinder and out through the zone f into the port 0 and through the latter down into the right end of the pump. The controlling-cylinder and the ports thus conditioned constitute a free communication between the ends of the pump. When the pump-piston G is, by the eccentric B and the connection G G carried to the left, the oil moves upward in the port 0, then to the right through the controlling-cylinder O and downward through the port 0 Whenimmediately afterward the pump-piston G moves to the right, the oil moves upward through the port 0 then in the reverse direction through C and down through the port 0. This is the condition under which the car usually works, subject to no resistance from my apparatus beyond a slight friction. When the car is moving at full speed and the pump-piston making its heretofore-idle reciprocations rapidly, the attendant shifts the brake-wheel or brake-handle in the proper direction to apply the brakes, (the same motion which he is accustomed to with the handbrakes.) He shifts the rod I, and correspondingly the rings I and 1 so that the rings cover each its proper zone. The passage through the controlling-cylinder is completely stopped. Now the reciprocations of the pump-piston become effective and the device works as a pump, the induction-valves D D and the delivery-valves E E rising and sinking in the long-known manner and with the long-known effect. Each movement of the pump-piston G to the left drives the oil from the left end of the pump-cylinder 0 up through the port 0, as before, and as it cannot go into the controlling-cylinder, as before, and cannot resist the impulse received from the powerful motion of the piston G it compels the delivery-valve E to rise and the full charge of the pump passes up through the passage thus opened. Thence it moves downward under the strong pressure induced by the pump through the port a into the brake-cylinder 0, moving the brake-piston M strongly to the left, and through the rod 0 forcibly operating the brake-beams P and putting on the brakes.

Oonfining our attention to the left end, each movement of the pump-piston Gr to the right draws oil from a small reservoir G which oil descends through a passage 0 (see Figs. 3, l, and 5) into a chamber a, and thence rises through the ind notion-valve D and descends through the same port 0. The action of the two ends of the pump are alike, alternating.

.Both force the brake-piston M in the same directionto the left. Each delivers into a chamber communicating with the same end of the brake-cylinder through the same port a.

The pump need not be large to put the brakes fully on in a very few revolutions of the car-wheels. It will often be the case thatthe velocity of the car is too great to be stopped in so short a distance. If it is desired to stop the wheels and have them slip on the track, the brake-cylinder and piston may be made sufficiently large to effect this. It is preferable not to slip the wheels, but to have them retarded'nearly enough to efiect that. To attain this, I provide a springloaded relief-valve R with provisions T for adjusting the tension of the springs. After the brake has been properly put on the oil overcomes the adjusted load and raises the valve R and discharges idly into the reservoir G the oil pumped during the last part of the slowing motion. The return movement of the brake-piston M is efiected by the aid of a spring L, coiled around the trunk M and urging the piston toward the closed end of C It is important to provide for the ready escape of the oil which has filled the brake-cylinder after its dutyis performed and it is released from the action of the pump. The function of the middle zone f is to facilitate this. This middle zone of the controllingcylinder is in free communication with the reservoir 0 The middle ring 1 keyed or otherwise firmly set on the rod I, covers that zone and makes it of no effect during the period while the brake is on, but when the rod I and its attached rings are again moved to the right in letting off the brakes this zone is uncovered and the oil, which has been under pressure in thebrakecylinder, is put into free communication with the reservoir, and it retreats as required by the return motion of the brake-piston.

A pipe 0 Figs. 1, 2, 4, and 6, forms the connection between port 0 and the reservoir to allow the oil to descend from the latter and reach the induction valves when the brake is put on. The same pipe allows the reflow of the oil back to the reservoir when it is forced out through the relief-valve R.

A separate pipe G, Figs. 1, 2, 4, and 8, constitutes the connection between the controlling-cylinder 0 and the reservoir C to provide for the idle flow of the oil back to the reservoir when the brake is released.

I claim as my invention- 1. In a car-brake actuated by fluid-pressure, the contiuuously-reciprocating piston G playing in a cylinder 0 with ports whereby the fluid may play idly from one end of such cylinder to the other alternately in opposite directions and a brake-cylinder, piston and connections for operating the brakes, and ports,valves and a controlling device, whereby the fluid can be thus moved idly or directed into the brake-cylinder at will, all combined and arranged substantially as herein set forth.

2. In a car-brake actuated by fluid-pressure, the continuously-reciprocating piston G playing in a cylinder 0 having ports 0 0 in combination with induction valves D, D serving with a supply-reservoir C deliveryvalves E E serving with a brake-cylinder O and a piston M in the latter, and proper connections therefrom to the brake devices I and with a controllable valve device serving to put the two ports in free communication and thus allow the fluid to reciprocate idly at will or to close such communication and cause the fluid to be pumped and thus to apply the brakes and with the screw-threaded guiding and adjusting case T inclosing a relief-valve R and a helical operating-spring, all substantially as herein specified.

3. In a car-brake actuated by fluid-pressure, the continuously-reciprocatin g piston G playing in a cylinder 0 having ports 0' 0 in combination with induction valves D D serving with a supply-reservoir C deliveryvalves E E" serving with a brake-cylinder C and a piston M in the latter and proper connections therefrom to the brake devices Pand with acontrollable valve device comprising the cylinder C with its zone f f and the rod I with its rings I I serving to put the two ports in free communication and thus allow the fluid to reciprocate idly or to close such communication at will and cause the fluid to be pumped and thus to apply the brakes all substantially as herein specified.

In testimony that I claim the invention above set forth I affix my signature in the presence of two witnesses.

BENJAMIN S. LAWSON.

Vitnesses:

WILLIAM PAXTON, M. F. BOYLE.

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