US1770043A

US1770043A - Slack adjuster

Info

Publication number: US1770043A
Application number: US62475A
Authority: US
Inventors: Willard F Richards
Original assignee: Symington Co
Current assignee: Symington Co
Priority date: 1925-10-14
Filing date: 1925-10-14
Publication date: 1930-07-08
Anticipated expiration: 1947-07-08

Description

w. F. RICHARDS 1,770,043

SLACKVADJUSTER Filed Oct.- 14, 1925 2 Sheets-Sheet l July s, 1930.

w attorney :Si: E

Patented `luly 8, 1930 g UNITED sjrAri-:s`y

mifrtlvrl ori-ICE WILLnRn F. RICHARDS, or nnrnmnnw YORK, AssIGNoR To THE sYMr-nG'rQN corr- PANY, or NEW YORK, N. Y., n CORPORATION or Mamani@ SLACK ADJUSTER Application filed October 14, 1925. Serial No. 62,475.

This invention relates to automatic slack adjusters and particularly those of the type disclosed in Sauvage Patent No. 1,114,295

of October 20th, 1914, and may be considered k as a modification of the slack adjuster described and claimed in the Kadel and Barrows application, Serial No. 39,348,1(iled J une i to permit ready connection and disconnectionwith respect to the car body and brake rigging'V and which involves various improved details of construction. Y

An obj ect of my invention is the provision of a slack adjuster for railway brake rigging La which is so connected with the car body that the necessary relative motion `with respect to said car body is freely permitted, thereby avoiding strain on the mechanismoand one end at least of said slack adjuster is .spring supported on said car body. n

Another object of my invention is the provision of an improved slack adjuster for rail-Y way cars in which the take-up rod thereof is returned to normal position after being re- .fil leased to suitably adjust the mechanism b a plurality of springs surrounding said ro means being provided for properly'centering said springs with respect thereto.

A further object of my invention is the pro- 315. vision of an improved slack adjuster for railway cars comprising a take-up rod formed with an eye threadedly connected with one end thereof and serving for connection with an associated live lever -on the car, whereby an i adjustment between-said rod andlive lever may be effected'.

A. still further object of my invention is the provision of an improved form of slack adjuster for railway cars in which the take-up 5*. pawl thereof is mounted von a suitably guided carriage connected to the take-up rod rather than being mounted directlyion said take-up rod, whereby improvement inoperation of the mechanism is effected. Y r3-0 Other objects and advantages of' the invention relating tothe particular arrangement and combination of the variousparts will become more apparent as the description proceeds.

Referring to the drawings illustrating my invention, the scope whereofviskdefined by the appended claims: Y l Y Figure 1 is a plan view, partly in Section, showing a slack adjusterembodyingmy invention connected to the body or underframe of a car shown only fragmenttrly.

Figure 2 is an elevational view, shown partly in section, of the slack adjuster shown in Figure 1. i

Figure 3 is a transverse sectional View on the line 3--3 of` Figure 2, looking in the direction of the arrows. Y Y

, Figure 4- is a transverse sectional viewoon the line i- 4L of Figure 1, lookingin the direction of the arrows, and showing'particularly an embodiment of my resilient supportingmeans used'in the present instanceat one end of a slack adjuster.v

vFigure 5'is a detail longitudinal sectional view of the take-up rod pawl carriage on the line5-5 of Figure 1, looking in thedirec-f tion of the arrows.

Figure 6 is an elevational view ofthe right hand end of the pawl carriageY shown in Figure 5.

Fi ure 7 is a plan view of a modified'form of ta ie-up rod pawl and carriage.

Figure 8 is an elevationalY view` of said modified form of pawland carriage, a por7 tion of the mechanism associated therewith being also illustrated.

Referring tothe drawings in detail,` similar parts being designated by like reference characters, there is indicated a part ofthe car nnderframe, such as one of thecenter sills 1 thereof and from said vcenter sill is supported myslack adjuster, indicated generally by the reference character 2, in a manlUD nection, in the usual manner, with brake beams carryingtheir respective brake shoes, butas such features are not part of the invention and are old in the art, as shown by said Sauvage patent, they are not illustrated. The corresponding` ends of the live and dead levers are Aadapted for connection by a usual form of bottom rod, as will be understood, and when no slack adjusteris employed the deadlever fulcruni is customarily attached to the bolster ofthe car.

such a connection is dispensed with and said dead lever is insteadr connected to the hook 3 of the rack bar 4, in any desired manner, as bymeans-of 'achain which is shown in the Sauvage patent `aforementioned, as will be understood. Likewise, thetake-up rod' is operatively connected withy respect to the corresponding end of the live lever or the pull frod connected therewith so that uponA j prises aphousing 6 formed as two compleconnected with a live 'lever of the car. j eye is preferably provided with a hub or nut mentary halves, preferably connected together by a plurality of rivets or bolts 7. In said housing, there is slidably mountedthe takeup rod 5,.,the outer or rear portion of whichy is provided with an eye `8 for connection with 'a linker operating rod` in turn operatively associated withfthe usual `pull rod Said portion 9 threaded'to the inner or `rear end of the take-up rod and preferably castellated, as indicated at 10, for the reception of a locking cotter or the like:11. `On ac-A count of such'construction, vthe eye 8 may be adjusted to a limited degree with respect to the take-up rod 5 Vand may be readily connected and disconnected with respect thereto. The take-up rod 5, at its inner or front end with respect tothe car, is formed with a preferably integral headed portion 12 adapted for connection with a pawlicarriage 13 upon which is vpivotally mounted a take-up pawl 14.4 Said headed portion .i12 of the take-up 'i .rod is preferably removably connected with said-carriage 131 asbybeing'inserted in the pocket 15 in said carriage with the adjacent portion of the take-up rod 'positioned inV the slot 16 in said carriage'13, the shouldered .portions formedV between the slot 16 and chamber 15 engaging'the headedportion 12 of .the take-up ,rod- 5 and preventing undesired disengagement therebetween. The carriage 13 is formedwith transversely-extending lug portions 17 guided in corresponding grooves 1 8 onthe inner faces of the housing 6 so that said carriage 13 and 4its associated Y pawl 14` are guided straight in the housing.

6 and are movedlin one direction or to the j the carriage 13 In'employing a` Vslack adjuster, accordlng to my invention,r

right, as shown in Figure 2, upon actuation of the take-up rod and to theleft by associated

springs

19 and 20 upon release of said take-up rod 5. j

The pawl 14 is preferably mounted in the carriage 13 by means of a pin' 21 extending throughthe rbearing or hub VVportion 22 of said pawl and supported by the side walls of the endsof said pin2o1being continued to the'` grooves 18 in housing 6, serving as additional means for guiding the pawl 14 and by this means also preventing loss of said pivot pin 21. The carriage 13 is preferably formed :with a forward extension or shelf'23 provided witha downwardly projecting lug 24 and uponwhich is positioned and centered a preferably helical pawl spring 25, the lower end of said spring being positioned around a similar lug 26 adjacent the outer or free end of said pawl. By means of this construction, the ypawl-14 is at all times urgedinto engagement with the `rack portion 27 of the rack bar 4.

In order to prevent undesired downward movement of the free or spring engaged por tion of the pawl 14, the hub portion 22 of said pawl is preferably formed with a lug 28 extending downwardly and toward the transverse wall portion 28 of the carriage 13, thereby limiting downward movement of said pawl 14. Y

The rear end of the take-up rod is slid ably mountedin a bearing member 29, said member being formed to fit .inV the corresponding end of the housing 6 and preferably retained in place in said housing by means of a `cotter 30, said cotter extending in the grooves 31 in said bearing 29 and through corresponding apertures in the adjacent housing portion. The inner side or left hand end l of said bearing, as kshown in Figure 2, is preferably formed with an annular extension y32 closely positioned with respect to the take-up rod 5 and formed of a diameter corresponding to the smallest diameter or inside dimension of the outer coil or helical spring 20 so as to form a bearingfor one end of said spring and serve ascentering means for said springs 19 and 20L Said .

springs

19 and 20, Ywhich serve forreturning the take-up rod 5to normal position upon release of the same, preferably extend `between said bearing 29 and the adjacent end of the pawl carriage 13, the other end of said springs being preferably centered with respect to the engaging portion of the pawl carriage by the innerspring 19 `fitting within the annular depression or groove 33 formed on said pawl carriage and of a diameter corresponding to the outer diameter of the linner spring 19.

As. an additional means for centeringthe springs one with the other, said springs 19 and are preferably wound in the opposite mannen That is, the'inner helical spring 19 may be wound right handedrand the outer edge or surface of the depending flange 36 from the ratchet`27 as well as the lower surface of the cylindrical portion 34 ofthe rack bar 4 bears on the lower wall of the housing 6, as illustrated particularly in Figure 3, a certain amount of clearance being preferably provided between the adjacent substantially horizontal surfaces on the rack 27 and the cylindrical portion 34 of the rackbar, as illustrated in said figure. The front or outer portion of the rack 27 is provided with a lip portion 37 adapted for engagement in a corresponding pocket 38 in the housing 6 to limit rearward movement thereof. The rear portion of the rack is preferably tapered orbeveled or provided with an extension, as indicated at 39, to facilitate assembly thereof.

As will be appreciated from a consideration of Figure 3, particularly, the rack portion 27 is generally T-shaped in cross section with the depending flange 36 engaged iny the bifurcated portion 35 of-the rack bar 4. rIhe ange 36, although partially cut away at its inner or rear end, is preferably continued at handle 42, said handle preferably normally depending and adapted for horizontal or -rotary movement.

On account of the differencein length between the bifurcated portion 35 of therack bar 4 and the rack or depending flange portion 36 thereof, the operating handle42 may be moved a substantial distance longitudif nally without affecting the rack 27, The object of such construction is to prevent injurious effect resulting from unauthorized persons tampering with the operating lever 42. However, upon pulling said leverto close up the distance between the right hand ends of the bifurcated portion 35 and the flange portion 36, said rack 27 may be manually moved the requisite distance to the left, if desired.

If at any time, it is desired to entirely release the rack from the take-up pawl 14 and the locking dog 43,7said handle 42 may be rotated through Vapproximately 90 in an Voutward direction about t-he rack bar 4 as an aXis, when said rack 27 is thrown out of engagement with the pawl 14 and the dog 43, the rack bar 4 will then be entirely released with respect thereto. The hook 3 may be provided with an abutment or stop portion 44 adapted to engage the adjacent portion of the lower wall ofthe housing 6 to limit the movement` of said rack bar 4 to the left.

The locking dog 43 is preferably. pivota'lly y the Ypinl 45 and the hub portion of the dog 43 to prevent frictional engagement therebetween so that said pivot pin 45, which serves to pivotally support the housing 6, does notI infiuence the action of the dog 43 on account of the weight imposed thereon from the housing. The operative or free end of the dog or pawl 43 is preferably pressed into engagement by means of a helical spring43, said spring preferably surrounding, at its lower end, an extension or lug 49 from the pawl and being housedk at its upper end in a pocket 50 in the housing 6.

vThe pivot pin 45, preferably headed at one end, as at 51, and provided with locking means46 at the other end, serves to support the housing 6V and contained members of the slack adjuster by extending through apertures in said housing and registering apertures in a trunnion ring or frame 52, said ring entirely encircling one end of the'housing 6 and being provided at its upper and lower ends, respectively, with substantially vertical or upright trunnion portions 53 and- The lower trunnion 54 is adapted forl 54. being supported by a bracket or anchorage 55 preferably extending from and connected to the lower surface of .the outstanding flange 56 of the center sill 1 by a plurality of rivets 57. In the preferred embodiment, there are two rivets 57 spaced relatively close, as indicated in Figure 1. The upper trunnion 53 is pivotally supported by means of the bracket or anchorage 58 preferably eXtending'from and bolted to the upper surface of flange 56. ln the present embodiment, two bolts 59 Vare employed spaced relatively far apart, as indicated in Figure 1 and outwardly of the rivets 57, that portion 0f the bracket 58, adjacent the heads of rivets 57, being cut away or provided with clearance holes60, as illustrated. By virtue of this construction, the lower bracket 55 is securely attached to the center sill and not readily removed therefrom, whereas the upper bracket 58 yis adapted for ready disconnection by merely removing the bolts 59 so that y the slack adjuster may be detached from the car, when desired. On account of the bracket 58 being cutaway at 60, adjacent the headsof the rivets?, thereisno interference between said bracket and rivets.'

On Yaccountfof. this form of support between the slackadjuster and housing and thev car underframe, a full universal 'connection is vprovided as horizontal angling is per-` mitted bet-Ween the frame or ring 52 and the

p brackets

55 and 58, whereas vertical angling is permitted between the housing 6 and the frame. l I

The other end of the housing6 is preferably supportedfor permitting relative vertical motion between saidhousing and underframe, said support, in the present embodiment, taking the formofa plate 61 riveted or otherwise suitably connected to the flange V62 of the center sill 1 and'extending down wardly and outwardly with a bifurcated and tion of the bolt' 64. The downwardly extending arms 67 of said U-shaped member 66 are preferably bent outwardly or transversely,

as indicated at 68, forming ledges or supporting means for the preferably helical Aspring 69 surrounding the lower portion'of the U- shaped member 66. A corresponding oridentical U-shaped`member 66a`preferably eX- tends between the depend-ing arms 67 of the U-shaped Vmember 66 and is surrounded by the spring 69, the outwardly extendingV portions 6 8n thereof engaging the upper end of the spring 69 andthe" lower or closed portion thereof receiving `a supporting bolt or the like 70 eXtendinO `throu h corres Ondine' ears orlugs 71, preferably integral with the housing 6. The'bolt 70 is preferably head-v ed, in the usual manner, andheld in place by means of a nut172 threaded tothe opposite end thereof, i

` It will beapparent that onaccount of this construction the slack adjuster housing is resiliently supported from the bracket 61 and Y. .the center sill of the car and it will be obvious that .the-weightof saidV housing and contained Vmembers tends to pull the U- shaped -member 66' from the inverted U- Vshaped member 66 and thereby compress the associated:'spring 69 therebetween. ANot only is this vertical movement allowed for at this end of the slack adjuster housing 6, but it will be apparent that angling motion is also pro- -thisexcess or abnormal motion.

vided ,for by virtue of thepivotal connections at the

bolts

64 and 70. p

Referring now to Figures 7 and 8, a modilied form of take-up rod pawl 14? and carriage 13 therefor is illustrated. The only material dilference between this construction and that of the previousmodication before.

described and illustrated, is that the pawl actuating spring25a, instead of acting vertically or between a substantially horizontal shelf portion 23 and the pawl `14 therebeneath, acts at an angle to the vertical, or substantially perpendicular or normal with respect to the engaged pawl portion. Instead of engaging lug portions at the opposite ends thereof, said spring engages a lug portion 24a from the sloping shelf portion 23a on the pawl carriage 13n,the other end ofsaid spring 25EL being received in a pocket 7 Sin said'pawl 14a. In other respects the construction of the pawl carriageand pawl may be identical with that previouslyl described. l

yThe operation ofthe aforedescribed slack adjusteris as follows:

When the brake shoes are new so that a normal amountof piston travel only is necessary to set thebrakes, the pull rod moves vduring the normal operation of said brakes a distance merely suficient to cause engagement with the actuating or connecting rod to take up rod 5 without motion of said take- .up rod. WhenV the brake shoes become worn to such an extent that it is necessary to move he pull rod an abnormal amount to apply the brakes sufficiently, movement of the takeup rod is effected, in the usual manner, and the same is drawn to the right, considering Figures 1 and 2, a distance corresponding to Such motion, if greater than the length of one of the teeth of the rack 27, will cause the pawl 14 or 14a, if the alternative construction is employed, to slide over one or more of said teeth, the engagement of locking dog 43 preventing said rack from being drawn Yto the right with the pawl 14. Upon release of the brakes, the' .take-up rod 5 is likewise released and the

springs

19 and 20 force said take-up rod'back to its normal position and on account of the engagement between the pawl 14 and Yrack 27 a movement of said rack to the left is effected together with the associated rack bar 4 corresponding to the tooth or num` ber of teeth over which said'pawl 14 has slipped when the brakes were applied. This movement of the rack bar to the left draws the corresponding end of the dead lever to the left andthroughthe connection between the dead and vlive levers effects a corresponding movement at the end of the live lever connected to the pull rod so that until further wear of the brake shoes has. taken place no further movement of the take-up rod is effected. -As will be obvious, when the rack 27 has been moved to the lefty by means of the take-up rod and pawl it will be locked in place by means of the locking dog 43.

From the foregoing disclosure, it will be apparent that I have devised an improved form of automatic slack adjuster' in which the necessary relative motion thereof, with respect to the car, is permitted` and in which the take-up pawl is so carried and guided that it at all times acts in the proper manner and that the various other parts are advantageously arranged and constructed so that the brake rigging is at all times maintained in the proper adjustment.

I-Iaving thus described the invention, I claim:

1. In combination, a car body, a slack adjuster mounted thereon and including two relatively movable members adapted for connection, respectively, with a live lever and a dead lever on the car, a housing for said relatively movable members, and a support for said housing comprising a bracket mounted on the car body and a depending resilient connector extending from the outer portion of the bracket to the housing.

2. In combination, a car body, an automatic slack adjuster mounted thereon and including two relatively movable members adapted for being operatively associated, respectively, with a. live lever and a dead lever on the car, a housing for said relatively movable members, and supporting means for said housing comprising a universal connection with the car body at one end thereof, and a spring supporting means at the other end.

3. In combination, a car body, a slack adjuster mounted thereon and comprising-arack bar adapted for connection with a dead lever on the car, a take-up rod adapted Vfor operative connection with a live lever on the car and for longitudinal movement in one direction upon excess movement of said live lever, a dog in operative engagement with said rack bar to prevent movement thereof in the same direction and permit free movement thereof in the opposite direction, a pawl carriage mounted on one end of the take-up rod, a pawl pivotally mounted on said carriage, a spring positioned between said pawl and carriage and pressing said pawl into engagement with the rack bar, means for turning said rack bar to disengage said dog and pawl, and a plurality of coaxial springs surrounding said take-up rod, and pressing against the carriage mounted thereon, to slide said rod in the opposite direction.

il. In combination, a car body, a slack adjuster mounted thereon and comprising a rack bar adapted for connection with a dead lever on the car, a take-up rod adapted for operative connection with a live lever on the car and for longitudinal movement in one direction upon excess movement of said live lever, a dog in operative engagement with said rack bar to prevent movement thereof in the same direction and permit-free movement thereof iny the; opposite direction, a housing forl said slack adjuster, saidy dogA being pivotedr with respect to4 said housing and spring-pressed against said rack bar, a pawl carriage connected to an end of the take-up rod and guided in'saidhousing, a pawl pivotally mounted on said carriage, a spring mounted between said carriage and pawl' and serving to urge said pawl into engagement with the rack bar, a handle on said rack bar for moving it to release said dog and pawl, and a plurality of springs mounted on said ytake-up rod between said carriage and housingand pressing said'V rod in the opposite direction.

5. In combination, a car body, a slack adjuster mounted thereon and comprising a rack baradapted for connection with a dead lever onA the car, a take-up rod adapted for operative connection with a live lever on the car and :for longitudinal movement in one direction upon excess movement of saidlivey lever, a dog in operative engagement with said rack bar to prevent movement thereof in thesame direction and permit free movement thereof in the opposite direction, a housing for said slack adjuster, said dog being pivoted with respect to said housing, a spring between said dog and housing to press said dog against'said rack bar, a bearing in said housing slidabl'y supporting said take-up rod, a [pawl carriage connected to an end of thetake-up rod and provided with guiding lugs `engaging in corresponding grooves inl the housing, a pawl pivotally' mounted on said carriage, a spring with the opposite ends thereof supported, respectively, on the carriage and pawl for causing said pawl -to engage the rack bar, and spring meansmounted on said take-up rod and acting between said carriage and take-up rod bearing to force the rod in the opposite direction. Y

6. Incombination, a car body, a slack adjuster mounted' thereon and comprising a rack bar adapted for connection Vwith a dead lever on the car, a take-up rod adapted for operative connection with a live leveron the car and -forlongitudinal movement. in .one direction upon excess movement of said live' lever, adog in operative engagement with'- saidrack Abar to prevent movement thereof in the same direction and permit free movement thereof in the opposite direction, a housing for said-slack adjuster, said dog being pivoted with respect to said housing, a spring between said dog and housing topress said dog against said rack bar, a bearing in said housing slid- Vably supporting said take-up rod, said bearing being provided with an annular longitudinal extension, a pawl carriage connected toan end of the take-up rod and provided with guiding lugs engaging in corresponding grooves in the housing and formed with a concentric annular groove around said take- Y up rod, a pawl i `pivotally. mounted Von said carriage, a spring at the opposite ends thereof` supported, respectively, on the carriage and pawl `for causing said pawl to engage the rack bar, a'spring closely mountedV on said take-up rodand acting between the annular groove on said carriage and the annular eX-A tension on the take-up rod bearing, and an outer spring surrounding said first spring and acting'between said carriage and takeup rod hearing7 said springs cooperating to move the rod in the opposite direction.

`7. In combinatioma car body, a slackadjuster mounted thereon and comprising a rack bar adapted for connection with la dead lever on the car, a take-up rod adapted for operative connection with'a live leveron the carf' and for longitudinal movement in one directionupon excess movement of said live lever, a dog for operative engagement with said rack'bar to `prevent movement thereof in the same direction and permit free movement `thereof` in the opposite direction, a pawl carriage mountedonv thetake-up rod, a pawl .pivotally mounted on said carriage and provided with a stop lug adapted for engagement with an adjacent wall of the carriage to limit downward movement of said paWl, a spring positioned between said pawl and carriagefand pressingsaid pawl into en gagement with the rack bar, and spring means toslide the take-up rod in the opposite direction. l j i l 8. Incombination, acar body, a slack adjuster -rnounted thereon andr comprising aA rackbar adapted for connection'with `a dead lever on the car,a take-'up rod adapted for operative connection with a live lever on the car and for longitudinal movement in oneV direction upon-excess `movement ofv said live lever, f the connecting means for said take-up rod `comprising acastellated nut portion threadedly engaging lone end of said takeup rod and provided 'with an eye portion for connectionwith the livelever, Cotter means insertedthrough the cooperating portionrof the take-up `rod and castellations of Vthe nut Y to holdsaid membersin adjusted position, a

doginl operative engagement `with 'said Vrack Vbafrto prevent movementthereoi'l in the same Y direction and permit "free movement thereof `in the opposite direction, a pawl associated Y with said takeup rod and spring-pressed into engagement-with :the raekV bar, and dspring means to slide Lthe take-up rod in the opposite direction, f f

i wir-LARI) RICHARDS;