US1567407A - Brake mechanism for railway cars - Google Patents

Description

Dec. 29, 1925. 1,567,407

H. 1. WRIGLEY BRAKE MECHANISM FOR RAILWAY CARS Filed Dec. 9, 1922 W75 oooono ooooooo coococ metal.

Patented Dec. 29, 1925.

NlTED STATES PATENT OFFICE.

HENRY I. WRIGLEY, OF CHICAGO, ILLINOIS, ASSIGNOR TO UNIVERSAL DRAFT GEAR ATTACHMENT GO., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

BRAKE MECHANISM FOR RAILWAY CARS.

Application filed December 9, 1922. Serial No. 605,872.

To all whom it may concern:

Be it known that I, HENRY I. WRIGLEY, a citizen of the United States, and resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Brake Mechanismsfor Railway Cars, of which the following 1s a specification, and which are illustrated 1n the accompanying drawings, forming a part thereof.

This invention relates to brake mechanisms for railway cars and has for its object, broadly, to give the hand brakes speed and power comparable to the air brakes.

More specifically, it is an object of the invention to embody in the brake rigging a cable cooperating with a sheave-like member in the form of a rotatably mounted reversing lever having arms of different length provided with peripheral working surface of considerable angular extent arranged to effect a quick change from one arm to the other and to give the mechanism a wide working range in applying the braking pressure.

Further objects and advantages of the invention will become apparent as the disclosure proceeds and the description is read in connection with the accompanying drawings showing a selected embodiment of the invention and in which- Fig. 1 is a fragmentary side elevation of a railway car embodying this invention.

Fig. 2 is an enlarged fragmentary view showing the parts in the positions they occupy when the brakes are off;

Fig. 3 is a view similar to Fig. 2 but showing the parts in the positions they occupy when brakes are applied;

Fig. 4 is a side elevation of the reversing lever; and

Fig. 5 is a transverse section thereof taken along the line 5--5 of Fig. 4.

Referring to the drawings, the reference numeral 10 indicates a suitable car underframe equipped with the usual brake step 11 on which is mounted a brake staff 12 equipped with a ratchet wheel 13 for cooperating with the pawl 14, and with the hand wheel 15 by which the hand brake mechanism is operated.

Below the car under-frame 10 is the usual air brake cylinder 16 equipped with a push rod 17 which is suitably connected to the brake lever. A hand brake rod 19, also of the usual construction, is connected at one end to the brake lever 18 and its opposite end cooperates with cable here shown in the form of a chain 20, having its dead end anchored to the brake step at 21 and its live end in winding engagement with the brake staff at 22.

In place of the usual sheave mounted in the forked end 23 of the brake rod is substituted a sheave-like member generally indicated by the reference numeral 24 and shown in detail in Fig. 4. This sheave-like member has a suitable hub 25, adapted to receive the pin or other bearing 26. In order to make the sheave as light as possible the body is made in the form of a web 27 (see Fig. 5) which carries the grooved or other suitable rim structure 28 in which the cable runs.

In Fig. 2 the parts are shown in their normal slack condition. When the brake staff is rotated the live end of the chain works with the speed of the short arm of the lever to make the throw of the long arm of the lever quickly take up the slack. Upon further movement of the live end of the chain to the right it shifts, by reason of the reversing of the lever, from the short arm to the long arm, and the dead end of the chain becomes engaged with the short arm whereby the brake staff is given the mechanical advantage of the lever in drawing the brake rod to the right and applying the brakes.

On account of the lack of space and other limiting circumstances, the shorter arm of the lever must necessarily be quite short, consequently if the working surface 29 thereof is made concentric with the hub 25 it will be too short to provide a wide working range for the brakes and it will make the step from the short arm of the lever to the long arm of the lever somewhat abrupt. For this reason it is preferred to make the working surface of the short arm of the lever eccentric to the hub and project it to the left side in Fig. 4. When thus arranged the speed of the long arm of the lever will slow up towards the end of the movement in taking up the slack and the live end of the chain will gain some mechanical advantage as the point of application of braking pressure is approached. Also the step of changing from the short arm of the lever to the long arm is made less abrupt though quick. This arrangement of the working surface 29 is also of great advantage when the parts take approximately the position shown in Fig. 3 for then this laterally extended working surface of the shorter arm provides for a con siderable further rotation of the lever in a clockwise direction (Fig. 3), while working efficiently to apply the brakes.

The working surface 30 of the long arm of the lever is provided with an extension 31, projecting to the right in Figure 4t opposite to the eccentricity of the working surface 29 of the shorter arm. This is desirable in order to continue the working surface 80 for cooperation of the live end of the chain as the parts continue to rotate clock-wise from a position shown in Fig. 8. Where it is desired to have the brake pressure practically constant throughout the entire-working range of the mechanism, the working surface 30 may be made eccentric in amount corresponding to the eccentricity of the working surface 29 so that the increase of the short arm leverage as the more eccentric parts of the surface 29 come into engagement with the dead end of the chain will be neutralized by a corresponding increase of the long arm leverage.

In order to save weight and metal it is preferred to make the right hand side of the lever in Fig. 4 concave substantially as illustrated. Adjacent to this concavity the web 27 is cut away as indicated at 82 (Fig. 4:) and the rim is thickened and perforated at 83 to receive a shackle 3st by which the chain is secured to the lever in the bight of the concavity. This arrangement makes it possible to gather up the chain when the parts are in a slack condition substantially as illustrated in Fig. 2, which not only eliminates objectionable sagging, but also determines to a certain extent the speed with which the slack will be taken up; for the distance of the point of attachment of the chain to the lever from the fulcrum or pivot of the lever materially affects the travel of the brake rod for a given angular movement of the lever.

From the foregoing, it will be clear that the reversing lever has working surfaces on its unequal arms arranged so as to shorten and facilitate the change from one end to the other in passing from the slack taking up operation to the brake applying operation and to provide for a wide working range in applying the braking pressure. The particular illustration is very well suited to certain classes of cars and from the information here given those skilled in the art will be able to properly design the working surfaces and locate them in such a way as to meet the requirements of other conditions.

I claim as my invention:

1. In a brake mechanism for railway cars, the combination of a brake staff, a brake lever and an extensible and contractable connection between said brake staff and brake lever including a reversinglever having arms of different length spaced apart angularly and provided with lateral extensions projecting in opposite directions, a cable formed into a bight about said lever with one end in winding engagement with said brake stafi and the other end anchored and means for eifecting a' driving engagementbetween said cable and'said reversing lever.

3. In a brake mechanism for railway cars, the combination of a brake stafi, a brake lever and an extensible and contractable connection between said brake staff and brake lever including a reversing lever having arms of different length spaced apart angularly and provided with peripheral working surfaces, a chain formed into a bignt about said lever with one end in winding engagement with said brake staff and the other end anchored, the working surface of the shorter arm being extended laterallyto give increased leverage to the live end of the chain in taking up'the slack and increased throw to the lever in applying the braking pressure, and means connected to said brake lever and-to the axis of said reversing lever for operatingsaid brake lever upon therotation of said brake stafi.

i. In a brake mechanism for'railway cars, the combination of a brake staff, a brake lever and an extensible and eontractable connection between said brake staff and brake lever including a reversing lever havingarms of different length spaced apart angular-1y and provided with peripheral working surfaces, a chain formed into a big-ht about said lever with one end in winding engagement with said brake stafi and the other end anchored, said arms hav ing oppositely directed lateral projections to increase the throw of the lever and correspondingly increase the working range of the mechanism.

. 5. In a brake mechanism for railway cars, the combination of a brakestaff, a brake lever and an extensible and cont-ractable connection between said brake staff and brake lever comprising a reversing lever having, arms of differentlengths, the shorter arm being provided With a lateral extension,

' the forward face of said lever being substantially straight and the follower face being concave.

6. In combination, a brake staff, a brake lever, a reversing lever having a long and a short arm, the short arm having a lateral extension, the face of said lever adjacent to said stall in the released position of the brake being concave, cable means secured to said concave face and connected to an anchor and to said brake stall, and means for connecting said reversing lever to the brake lever, said means constituting the sole snpportfor said reversing lever.

7. In a brake operating mechanism, a reversing lever having an aperture therethrough forming. a bearing for said lever, said lever having a long and a short arm and said short arm being laterally extended, each end of said lever being grooved for the engagement of a flexible operating member.

8. In a brake operating mechanism, a reversing lever having an aperture therethrough forming a bearing for said lever, said lever having a long and a short arm, said short arm being laterally extended and one of the edge faces of said lever being concave, each end of said lever being grooved for the engagement of a flexible operating member.

HENRY I. VVRIGLEY.

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