US2642963A - Slack adjuster - Google Patents

Description

June 23, 1953 QOBINS'QN 2,642,963

SLACK ADJUSTER Filed Oct. 14, 1946 s Sheets-Sheet 1 INVENTOR. JOSEPH Roam/sou J. ROBINSON SLACK ADJUSTER June 23, 1953 5 Sheets-Sheet 2 Filed 001;. 14,;946

I N V EN TOR. J0 SEPH Ros/-50 HTTOIPAE June 23, 1953 J. ROBINSON SLACK ADJUSTER 5 Sheets-Sheet 4 Filed Oct. 1 4, 1946 QNfiE R O ww 3v 3w m ms a?! fi f a 0 v hm P0 M m. w mm. Z w m M w H ,fl w n, V- B um ,o $.w f I% ww J. ROBINSON June 23, 1953 SLACK ADJUSTER 5 Sheets-Sheet 5 Filed Oct. 14, 1946 INVENTOR. JOSEPH Roam/sou Patented June 23, 1953 UNITED STATES PATENT OFFICE SLACK ADJUSTER Joseph Robinson, New York, N. Y. Application October 14, 1946, Serial No. 703,258 2 Claims. (01. 188-197) This invention relates to'slack adjusters for removing undesired slack in the brake rigging of railway cars due to brake shoe wear. It is an improvement on the slack adjuster shown in my United States Patent #2,190,681, granted Febru ary 20, 1940. A primary object is to provide a simple and compact adjuster which by a simple "pull and let go operation instantly takes up the brake shoe slack at either or both ends of the car, and which can be re-set without workmen having to go under the car or between the ends of opposing cars. Other objects and advantages of my improvement are described in the following specification, pointed out in the appended claims and illustrated in the accompanying drawings in which:

Figure 1 is a small scale plan View of a typical application of my improved slack adjuster to the brake cylinder and brake rigging of a car;

Figure 2 is a small scale plan view, similar to Figure 1, showing a typical application of my improved slack adjuster to the center sill of a car;

Figure 3 is an enlarged side elevation of my improvement and a part of the brake cylinder shown in Figure l, the adjustment lever C and the release rod G being shown in section;

Figure 4 is a top view of the construction shown in Figure 3 with a part of the member 21 broken away;

Figure 5 is a bottom view of the construction shown in Figure 4; Figure 6 is a sectional detail taken on approximately the line 6-45 of Figure 3;

Figure '7 is a rear view of the construction shown in Figure 3. In-this View a part of the brake cylinder is broken away, and the adjustment lever C and the release rod G are shown in elevation;

Figure 8 is a detail in. elevation showing the pivoted link F at the limit of its rearward swing, and the ratchet bar E at the moment of initial adjustment Figure 9 is a view similar to Figure 8 showing the ratchet bar and link in the position they assume when the :bar moves through the link for adjustment, and

Figure 10 is a sectional elevation of the construction shown in Figures 8 and 9 with the ratchet bar in one of its adjusted positions and interlocked with the link F preparatory to swinging the link forward to the limit of its movement.

Referring to the drawingsz-In Figure 1 my improved slack adjuster A is shown attached to the rear end of a conventional air brake cylinder B. A general arrangement of the brake rigging, or foundation brake equipment, operated by my immovement is schematically indicated in this view, and brackets ll, l2 and M are shown for supporting parts of the brake equipment. The ends l5, l6 and I! of the brackets serve as stops for limiting the movement of the levers C-D each of which, as shown, is operatively connected with the brake rigging of the car. The brake rigging includes transversely arranged suitably supported brake beams, not shown, which are provided with :brake shoes that are drawn against the periphery of the car wheels, not shown, when levers C and D are actuated by the piston within the cylinder 13, Figure 1. This arrangement is generally indicated in Figure 1 of my aforesaid United States Patent #2,190,681 in which 23 designates a brake shoe head carried at one end of a brake beam in the brake rigging of the car. Normally a predetermined amount of clearance or free slack, usually about 2%", is maintained between the brake shoes and the car Wheels collectively when the brakes are in the releasedposition. How this clearance or free slack is provided and maintained with the present invention will appear hereinafter.

If the cylinder B is not provided with the usual attachment lug l8, Figure 3, any suitable substitute for it may be employed. To this lug or to its substitute my improved slack adjuster A is suitably anchored as by means of bolts l9. Immunity to the serious operational difficulties experienced with present types of slack adjusters due to the accumulation therein of foreign matter, such as snow and ice, is effectively obtained by constructing the body or housing of my improvement in the form of a frame comprising the member or cover plate 2 I preferably U-shaped in cross section to stiffen it and to span the attachment lug l8, Figures 4 and 6, and a pair of laterally spaced horizontally disposed carrier irons 22 having any desired cross sectional form. The rear ends of these irons are upwardly turned at 23,- Figure 3, and pass through the member 2| and are riveted thereto at 24, or are otherwise suitably secured thereto. The front ends 25 of the irons are widened and are ofiset downwardly to engage with the attachment lug I8, Figure 3, the lug serving also to space the front ends of the irons with respect to the plate 2|. Bolts I9, or other suitable securing means, rigidly anchor the front end of the plate 2| and the carrier irons 22 together as well as to the attachment I8 on the cylinder B. A spanner 26 through which the bolts l9 pass embraces the front ends of the the upwardly turned rear ends 23 of the irons serving as stops for limiting the reaward travel of the lever. Between these irons and below the plate 2| I mount a ratchet bar E having a plurality of rugged teeth 21. The front end of the bar is forked at 28 to receive the pivotally anchored thereto by the pin 29, the pin being inserted through the opening 39, Figures 3 and 4, in the plate 2|. The ratchet bar E extends rearwardly from a point immediately behind the cylinder B to a point beyond the rear ends of the carrier irons 22 and passes loosely through the opening 3|, Figure 8 in the pivot or adjustment link F. The link is provided at the bottom of its opening with a heavy lug or tooth 32 which meshes or interlocks with the teeth 21 of the ratchet bar E. A fiat bearing surface 33, Figure 8, formed on the upper rear wall of the opening 3| in the link engages the fiat top of the ratchet bar and coacts with teeth 2l--32, Figure 3, to powerfully lock the bar against forward movement in the link F from any of its service positions. The link spans and is pivoted in any desired way, as by the pin 34, Figures '7 and 8, to a vertically disposed lug 35 suitably arranged on the rear end of the plate 21 and extending rearwardly thereof and of the carrier irons 22. To prevent undesired extraction of the ratchet bar from the link F, and

under certain conditions to swing the link forward to the limit of its movement, a stop device 36, Figures 3, 5 and '7, is removably mounted in or on the rear end of the bar by suitable means such as the cotter pin 31.

When the brake rigging of the car is in the normal released position, a certain amount of clearance or slack is, of course, necessary between the rim of the car wheels and the brake shoe. To provide this clearance or slack the link F is free to pivot or swing forward on its pivot pin 34 from the position shown in Figures 8, 9 and 10 to the position shown in Fig. 3, the extent of this movement being such as to provide the desired free slack. Forward swing of the link is limited by engagement of its upwardly extending projection 38 with the bearing 39 on the lug 35, whilst rearward swing of the link is limited by engagement of its projection 38 with the finger or stop 40 of the lug, Figures 3, 8, 9 and 10. When the link reaches the limit of its rearward movement, Figures 8-1.0, its inclined face 4| assumes approximately a horizontal position at which time the interlock of the ratchet bar E with the link F, Figure 8, is released and the bar is free to rise in the opening 3| in the link and slide rearwardly over the tooth 32. While the link F is in this rearward position the rear face 42 of its tooth, Figure 9, is at a forward angle to the vertical. The arrangement facilitates movement of the bar E forward in the link F from the position shown in Figure 10, for instance, to the position shown in Figure 8. This movement of the bar is made when it is desired to replaceworn out brake shoes and re-set my improved slack adjuster to the initial service position shown inlever C and-is Figures 1, 2 and 3. The re-setting is accomplished by moving the link F, through the medium of the lever C, Figures 1 to 5, to the limit of the rearward movement of the link, Figures 8, 9 and 10, and by retaining it in that position by means of the rotatable release rod G, Figures 1 to 5 and '7 and 10. This is accomplished by providing the link F with an integral laterally extending projection 43, Figures 3, 4, 5 and 7, against which the arm 44 of the release rod G engages to hold the link at the limit of its rearward movement, Figure 10, when the handle 45, Figure '7, of the rod is manually rotated to the left to its full extent. The rod extends through and is supported by a bracket H, Figures 1, 2 and 7, which is suitably attached to the car body, the rod being rotated in the bracket by the aforesaid handle 45. The arm 44 passes down through the opening 46, Figure 7, in the head 41 of the pin 34, and is removably retained therein by a cotter pin 48.

The adjustment lever C, and the release rod G extend horizontally from my improved slack ad-. juster to a point approximately flush with the side of the car making it unnecessary for a workman to go under or between the cars to operate or re-set. To take slack with my improvement it is only necessary to push or pull to the left, Figures 1, 2 and 3, on the handle 49 of the lever C as far as it will travel, then let go. The first effect of this is to swing the link F to the position shown in Figures 8, 9 and 10, and the next effect is to cause the ratchet bar E to slide through the link F to the extent of any slack that may exist in the brake rigging due to brake shoe wear. Immediately the push or pull on the lever is released, one of the teeth 2'! of the bar E will drop into interlocked engagement with the tooth or lug 32 of the link. The bar and the link will then swing forward until the link engages its bearing 39 of the lug 35, Figure 3, thereby establishing the desired free slack. To replace worn out brake shoes the lever C is pulled or pushed to the left as far as it will go. This swings the link F to the position shown in Figures 8, 9, and 10. Withone hand the operator holds the link in this position through the medium of the release lever G and its handle 45, Figure 10, and with the other hand he shoves the lever C forward to the limit of its forward movement, which is to say to the position shown in Figure 3. During this operation the stop 36 on the ratchet bar E engages the back of the link F and swings the link forward to the limit of its forward movement shown also in Figure 3 and into interlocked engagement with the ratchet bar E. This simple operation re-sets my improved slack adjuster for easy removal and replacement of worn out brake shoes, proper free slack or clearance for the new shoes being established by the forward wing of the link F from the position shown in Figure 8 to the position shown in Figure 3. The compactness of my improved slack adjuster gives it a short overall length. In consequence, support from the car body for the rear end of the adjuster has not been found necessary, but I show for this purpose a suitable bracket 50 secured to the lug 35 by a rivet or other means 5| and attached to the car in any way desired. The construction of the essential parts of my improvement is the same whether it is attached to the brake cylinder B, Figures 1 and 3, or to a part of the car body, as in Figure 2. For this reason I have referred broadly herein to the lug It as an attachment and have so numbered the attachment bracket l8 in Figure 2,

What I claim is:

1. A slack adjuster comprising, in combination, with a brake cylinder, an attachment lug on the brake cylinder, a pair of parallel horizontally arranged carrier irons secured at one end to the attachment lug and turned upwardly at the opposite end, an elongated cover plate riveted at one end to the upwardly turned ends of the said carrier irons and detachably secured at th opposite end to the upper side of the attachment lug thereby providing a frame to protect the slack adjuster from accumulation of foreign matter thereupon, a bracket securing the end of the frame remote from the attachment lug to the car, an adjustment lever supported by said carrier irons and operably disposed between the carrier irons and the elongated cover plate, said adjustment lever being connected with the brake rigging of the car and extending horizontally across the longitudinal axis of said adjuster through said frame to a point adjacent the side of the car, a link pivoted on said frame and disposed at the opposite end thereof relative to the attachment lug beyond the bracket and a ratchet bar pivoted to said adjustment lever and adjustably engageable with said link for cooperating with the link to remove undesired slack in said brake rigging at either or both ends 01' the car when the link is swung to the limit of its movement in one direction and to preserve desired slack therein at either or both ends of the car when the link is swung to the limit of its movement in the opposite direction.

2. A slack adjuster as described in claim 1, wherein means are provided for holding said link at the limit or its rear movement while the ratchet bar is moved forward in the link to reset said slack adjuster, said resetting being accomplished from a position adjacent the side of the car.

JOSEPH ROBINSON.

References Cited in the file of this patent UNITED STATES PATENTS

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