US2250993A - Coupler - Google Patents

Description

July 29, 1941.

COUPLER I 4 Sheets-Sheet 1 Filed May 4, 1939 QM QM NW Q; m @v \on glwwtzk w w w? N 5 WE Q Q IIIII m n a. v 3- v x w Mm x QR A X1 QM v y 29,1941. E. PQKME m. 22

COUPLER Filed May 4, 1939 4 Sheets-Sheet 2 July 29, 1941. E. P. KINNE ETAL COUPLER Filed May 4, 1939 4 Sheets-Sheet 3 July 29, 1941. E. P. KINNE ETAL COUPLER Filed May 4, 1959 4 Sheets-Sheet 4 iiz:

I INVENTOR. lamwzcifjwzw,

' ATTORNEY.

Patented July 29, 1941 UNITED STATES PATENT OFFICE COUPLER.

Edmund P. Kinne and Frank H. Kayler, Alliance,

Ohio, assignors to American Steel. Foundries, Chicago, 111., a corporation of New Jersey Application May 4, 1939, Serial No. 271,808-

20 Claims.

This application is a continuation-in-part of our copending application, Couplers, Serial No. 123,346, filed in the United States Patent Ofiice February 1, 1937.

Our invention relates to railway car couplers couplers-1 angling horizontally and vertically. A

certain amount of clearance has also been provided in such arrangement to permit satisfactory operation of the parts in coupling.

In the above mentioned Kayler Patent No.

2,098,207, approximately two thirds of this free slack has been changed to controlled slack through use of the resilient cushion type knuckle. The remaining clearance between the knuckle face and. the face of the mating coupler is retained and is necessary to'facilitate coupling.

Acertain amount of looseness in the fit of the various coupler parts is also necessary in order that they may be movable with respect to each other, and that they may be interchangeable without being held to unnecessarily close manufacturing tolerances. This is particularly, true of railway car couplers in which the parts areused as cast and are not subject to machining operations.

As the various parts of the couplers are worn in by service, additional slack develops; of course, between the parts where rubbing takes place. It has been found that this looseness results in noise in the operation of the couplers, especially when cars are running with little or no pull or buffing pressures between the couplers.

This" requires the'elimination of'noise as far as practicable and: reductiorr of shocksand'jerks which often develop in a train with uncontrolled slack.

It isan object of'the present invention to so designarailwaycar coupler that wearbetween the parts will not result in free slack between mated-couplers.-

O'ur: invention comprehends a form of control for? soi-called free slack in a coupler which will be applicable to present standard car construction and in particular to standard passenger-car types.

The; present invention providesfor control of all free-slack betweencouplers, including control of the small amount of free slack which remains in couplers fitted with cushion type knuckles, as covered by Kayler Patent No. 2,098,207.

A further purpose of our invention is to provide such adesign of slack-free coupler while; at

the'sa'me time, maintaining the feature of in- 20' terchangeability with present standard car couplers in use.

Our invention also comprehends a slack-free car coupler wherein all of the parts will be interchangeablewith the corresponding parts in present standard A. A. R.- coupler designs.

A. still further purpose of our invention is to so design a slack-free coupler that none-of the parts will require machiningand that such parts may ber produced. under the same manufactur- =ing; conditions as coupler designs'at present in use... 7

Our invention also comprehendsa carcoupler which .will automatically compensate for loosenbetween the partsdue tothenormal seating therebetween or to wear which develops under ordinary-conditions of use.

Olur invention likewise comprehends a design of. coupler wherein abutting parts of two mated .01) coupled couplers will at all times be=under compression-against-each other, thus preventingjolts andjars between themwiththe concomittantnoise.

. Alyetfurther object of our invention isan improvement in the: ability-to couple mated couplers from positions. of. increasing lateral angularity.

With these and various other objects in view, our inventionmay consist of certain novel features'of construction and-operation as will be morefully described and particularly pointed out in the specification, claims and drawings appendedhereto.

In the'drawings'which illustrate embodiments of'the device'and' wherein like reference characters are used to designate like parts- Figure 1 is a top plan view of a car coupler embodying our invention, the tail portion of the coupler being cut away;

Figure 2 is a fragmentary front elevation of the car coupler shown in Figure 1 illustrating the lug structure on the knuckle side of the coupler head;

Figure 3 is a fragmentary elevational view from the guard arm side of the coupler structure shown in Figure 1, with the plunger removed from the assembly;

Figure 4 is a fragmentary front elevational view of the guard arm side of the coupler;

Figure 5 is a sectional view through the guard arm side of the coupler shown in Figure 1, the section being taken substantially inthe plane indicated by the line 5-5 of Figure 1;

Figure 6 is a section similar to that shown in Figure 5, the section being taken also through the guard arm but forward of that shown in Figure 5 and substantially in the plane indicated by the line 66 of Figure 1;

Figure 7 is a side elevation of the plunger;

Figure 8 is an end View of the plunger;

Figure 9 is a plan View of the plunger asso- Figure 12 is a top plan view of two couplers embodying our invention in normal pulling position;

Figure 13 is a view similar to Figure 12 except that the couplers are angled laterally the maximum amount permitted by the contours under coupled conditions.

Figure 14 is a top plan view of a modified form of car coupler embodying our invention;

Figure 15 is a sectional view through the guard arm portion of our invention shown in Figure 14 and taken substantially in the planes indicated by the line l5l5 of Figure 14;

Figure 16 is a top plan view of two couplers of the modification shown in Figure 14 in, normal pulling position, and Figure 17 shows them angled laterally the maximum amount permitted under coupled conditions; and

Figure 18 is a side elevation of two couplers of the modification shown in Figure 14 in normal coupled position.

Describing our novel structure in more detail, the coupler head generally designated 2 (Figure 1) comprises the knuckle 4, of the improved design described in detail in the above mentioned Kayler Patent 2,098,207, pivotally mounted as at 6 in the manner of the present A. A. R. standard; and comprises also the guard arm 8 having a contour conforming in general to that of the present A. A. R. standard coupler except for the slightvariance near the end of the guard arm contour as shown at It). I

On the knuckle side of the coupler head is integrally cast the lug l2 recessed as at 14 and reinforced by the upper and lower ribs l6 and 18. The outer portion of the lug I2 projects forwardly as at 28 for engagement with the opposing face of the guard arm plunger, hereinafter more fully described, when two couplers are coupled (Figure 12).

The guard arm 8 is considerably enlarged as compared with the present A. A. R. standard and has incorporated therein a spring pocket 22 having the upper and lower cavities 24 and 26 respectively for the reception of coil springs 28 and 3E). The centrally located horizontal reinforcing wall 32 divides the spring pocket 22 into the above mentioned upper and lower cavities. The springs 28 and are positioned in their respective cavities by the bosses 34, 34 at the bottoms of the cavities and also by the central reinforcing wall 32 as well as by the top and bottom walls 36 and 3B of the guard arm plunger generally designated 46] (Figures '7 to 10, inclusive). The springs 28 and 39 are retained in position at their forward ends against the front wall of the guard arm plunger 40 by the centering bosses 42, 42 and the guard arm plunger is retained in position after assembly with the springs 28 and 39 under some initial compression by the rivet 44 against which abut the lugs 46, 46 integrally formed on the rear end of the guard arm plunger.

The guard arm plunger 40 is shown in Figure 1 in its normal position after assembly with the springs 28 and 38 under some initial compression and urging the plunger outwardly, said plunger being retained in the position shown by the abutment of the lugs 46 (Figure 9) against the rivet 44. In normal uncoupled position shown in Figure 1, it will be observed that the outer face 48 of the guard arm plunger 40 extends somewhat beyond the forward extremity 50 of the guard arm 8. When coupled and in normal pulling position (Figure 12) the plunger is depressed somewhat from the position shown in Figure 1 by engagement with the projecting end 20 of the lug 12 on the opposing coupler. Maximum rearward movement of the guard arm plunger 40 is limited by abutment of the forward extremity 50 of the guard arm against the recess at M on the lug 12 of a mating coupler as at 54 (Figure 13). This maximum rearward movement of the plunger occurs under conditions of lateral angling when in coupled position as shown for example in Figure l3. 7'

. The guard arm plunger 49 is shown in detail in Figures 7 to 10, inclusive. It is a one-piece structure, generally U-shaped in form, having top and'bottom walls 56 and 58 respectively, cylindricalin shape on their inner faces as at 59 (Figure 10) to conform to the shape of the enclosed springs 28 and 38; and a front wall 60 on the inner'face of which are formed the bosses 42, 42 serving as positioning means for the outer ends of the coil springs 23 and '30 as previously described. Integrally joining the top and bottom walls 56 and 53 and the front wall 60 is the lateral wall 62 and the horizontal reinforcing rib 64. Centrally located on the outer wall at the forward end of the plunger is the positioning lug 66 which may be received within the similarly shaped slot 68 (Figure 3) formed in the forward edge of the outer wall 10 of the guard arm 8. Along the edge of the plunger 40, opposite the positioning lug 6B, is formed the slightly raised lip 12 serving to increase slightly the gathering range under conditions where couplers are offset in a horizontal direction, and tending to retain engagement with the projecting end .20 on the lug l2 of a mating coupler.

In operation of our improved coupler, control of the contour slack is accomplished in the following manner. As the mated couplers are forced into closer engagement from the normal pulling position shown in Figure .12, the first portion of the movement iscontrolled by the pressure of the plungers- 40, 4 on the respective couplers having engagement with the opposed projecting ends 26, 20 on the lugslZ, l2. After such preliminary movement, the bufling plates 14, M of the mating knuckles engage the mating coupler faces as at 16, 16 and greatly increase the force controlling the remaining movement permitted by the contour. The total force then operative is that provided by the cushion type knuckles, as described in the above mentioned Kaylerpatent, plus the force exerted by the guard arm plungers as hereinafter described.

After the bufiing plates 14 come into engage- .ment with the mating coupler faces, the force required to move the couplers closer together is greater than the force normally required under present standardconditions to start movement pf the conventional. draft gear used in connection ithsuch couplers, thus the slack controlled facilities of our improved coupler become as effective incontrolling. contour slack as if the contour movement was. positively limited by unresisting means such as is in use on a certain type of couplers generally known as tight-lock couplers.

From the above and from the consideration of the drawings shown herewith, particularly Figures 1 and 14, itwill be apparent to those skilled in the art that the relatively small guard arm springs supporting. the guard arm buffer are of small capacity in comparison with the springs supporting the cushion knuckle. In actual practice we have provided several times as great capacity per inch of travel in the knuckle springs as compared with the springs in the guard arm. It will be appreciated that the comparatively low build up of capacity in proportion-to the travel in the guard arm springs is necessary to permit the normal coupling operation in which it would not be practical to compress springs of the capacity referred to in the above mentioned Kayler cushion knuckle wherein the initial capacity of the cushioningsprings is described as approximately equal to that secured at the beginning of .travel in standard draft gearsfor passenger cars.

In other words, the springs in the cushion knuckle, upon application are compressed a large proportion of their travel and, therefore, further compression of these springs is resisted by-like proportion of their solid capacity. On the other hand, the springs in the guard arm are compressed a relatively small amount upon application, and only a minor proportion of their travel and, therefore, offer resistance equal to a relatively small proportion of their solid capacity. In addition, the solid capacity of the springs in the guard arm is relatively small as compared with the solid capacity of the cushion knuckle springs.

Straight line coupling under normal conditions may take place between two couplers embodying my invention or between one such coupler and an A. A. R. standard coupler without compression of the cushion knuckle buffing plate, but in every couplin operation between two couplers embodying our invention, some compression of the guard arm plungers necessarily takes place. For this reason also, the guard arm plungers must be relatively free inmovement and supported by springs of relatively small capacity as compared with the springssupportin'g the cushion knuckle. If the-guard arm plunger spring were too stiff, thecoupling-action would be prevented and the mating couplerswould be forced away from each other resulting in failure-to couple.

As shown in Figure 11, the guard arm plunger-s, in addition to operating to control the contour slack, act to bring the couplers into axialalignment when being coupled from an angular position. In the case particularlyof lon shank coupler of'the present standard design,- satisfactoryl coupling, up to the theoretical maximum coupling angle is-not practical because of i buckling or. jack-knifing of the couplers, asit-is commonly. called, to a position ofangularity beyond the coupling range. This bucklingis due to the fact that the line of .force from one coupler butt pivot to. the other passes outside of the contact point of the knuckle. with the mating. coupler face,

As shown in. Figure 11, the contact of the plunger face 48. with the projecting end 20- of the lug l2 liesa greater distance from the'coupler center line than isthe case in standard couplers so-that under full angled conditions the lineof force. shown at l8. betweenthepivot point 89 of. one coupler and the pivot point 82 of the other coupler, along which the couplers aremoving. toward each other,.lies inside ofthe contact point at 84. Movement of. the plunger is resistedby sufficient pressure of the springs Ziiand 3.0 to cause the couplers to be moved over into axiaialignment, thereby accomplishing the coupling or locking of. the couplers and bringing theminto theposition shown in Figure 12, thus, with our improved type of coupler, the coup-ling operation can be accomplished from greater angles andin a more. positive manner than is possible with, couplers of the present standard design.

Where the coupling operationis tobe effected between cars. having a. limited provision for lateral angling or between two cars ona sharp. curve, couplingcan be effected under greater angularity than is possible with the. present standard couplers since the. pressure exerted in the first contact point. 84 between the plunger on one coupler against the lug on a, mating coupler acts to prevent the couplers from buckling and to keep them within the .angularity range of coupling.

Figure 13 illustrates how our improved coupler may angle the full amount provided for in the presentstandardv A. A. R. coupler. When this occurs, the guard arm plunger of one coupler and the knuckle bufiing plate. of the mating coupler are both compressed. as shown in Figure 13. When conditions permit, these pressures act to return the couplers to axial'alignment and, thus, tend. to decrease the pressure of the wheels against the outside rail ona curve i The modification shown in Figures 14 to 18., inclusive, is similar. in function to thatpreviously described, but differs therefrom in that this. modification is arranged to couple with the tight lock coupler relatively recently adopted as a standard on'American railroads. In order to accommodate couplingwith said tight lock standard, the modification at present under discussion is constructed with a relatively long guard arm. The parts of this modification are similar in function to those of that previously described with certain diiferences. of detail, more particularly referred to hereafter.

The coupler head comprises the pivoted cushion knuckle 92 of the form above referred to and describedniore particularly in Kayler Patent 2,098,207., said knuckle being pivotally mounted at. in the manner of the present A. A. R.

standard. The coupler head comprises also the guard arm 96 having a contour conforming in general to that of the present A. A. R. standard to about the point indicated at 98.

On the knuckle side of the coupler head is integrally cast the lug I recessed as at I02, said recess being defined by the rear wall I04 and the top and bottom flanges I08 and H0 (Figure 18), said rear Wall being reinforced by spaced horizontal ribs I06, I06 (Figure 18). The said rear wall I04 of the recess I02 affords abutment for the guard arm plunger of a mating coupler, said plunger being afforded vertical movement in the space between the before mentioned top and bottom flanges I08 and III] in order to accommodate coupling between two couplers at varying levels.

The guard arm 96 is relatively large and elongated and has the generally rectangular cavity II2 extending throughout its length and open at the forward end thereof for reception of the slidable hollow plunger II3, which is seated therein. A relatively long coil spring H4 is housed atpthe forward end within the hollow plunger I I3 and at its rear end within the guard arm cavity II2 abutting the base of said cavity as at I I6 against which it is positioned by the lug II8. Also housed within the cavity H2 is the relatively short spring I20 surrounding the inner end of the spring H4 and having abutment as at I22 with the inner end of the plunger I I3. The outer side of the plunger H3 is notched as at I24 and I26 to form stop means for engagement with the plunger retaining rivet I28 positioned centrally of said guard arm. The capacity of the springs engaging the guard arm plunger H3 is relatively small in comparison with the capacity of the springs in abutment with the buffing plate I4 of the cushion knuckle, thus accommodating normal coupling as above described. 7

Figure 16 shows the normal coupler position of mated couplers such as those just described, and Figure 17 shows the same couplers under maximum lateral angling when coupled. From a consideration of Figures 16 and 17, it will be clear that in normal coupled position the guard arm plungers IIS are only slightly compressed. Rapidly increasing resistance is offered thereby as the couplers are increasingly angled with respect to each other until the plunger of one coupler is compressed a maximum as seen at I30 (Figure 17) At the same time, one of the cushion knuckles is likewise compressed as indicated at I32 and the force of the springs thus compressed retains the opposed coupler heads'in tight relationship with each other preventing play therebetween and lost motion. When conditions permit, these pressures also act to return the couplers to axial alignment as described for the previous modification. From a consideration of Figure 16 it will also be apparent that very slight relative movement can occur between the couplers in normal coupled position before the cushion knuckle is brought into operation in addition to the guard arm plungers due to the slight space or clearance permitted between each cushion knuckle as at I34 and the opposing face of the coupler head.

Vertical angling in the contour between mated couplers of our improved design is provided for as with present standard couplers and,:in such a movement, partial compression of the guard arm plungers occurs as well as partial compression of the top or the bottom of the knuckle bufiing plates. Our improved'coupler is operative in conjunction with all present standard designs of A. A. R. couplers, but when a coupler of the present A. A. R. standard is connected to our improved design, the slack control feature is limited to. that provided in the single cushioned knuckle. The slack control features shown in our improved coupler design are not limited to couplers of the present A. A. R. standard or to couplers interchangeable therewith, but may be applied to any knuckle type coupler.

It is to be understood that we do not wish to be limited by the exact embodiments of the device shown which are merely by way of illustration and not limitation as various and other forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.

We claim:

1. In a car coupler, a head, a resilient knuckle pivoted in said head, a lug integrally formed with said head, said lug comprising a projecting por; tion and a recessed portion, a guard arm opposite said knuckle, said guard arm having a projecting portion and a recessed portion, a cavity in said guard arm, and a resiliently mounted plunger in said cavity, said plunger having a bufiing face normally extending outwardly of said projecting portion of said guard arm and being retractable under buff of an opposing coupler to a position where said face lies substantially within the plane of said recessed portion of said guard arm, said resiliently mounted plunger having a relatively light capacity per unit of travel as compared with said resilient knuckle, whereby the coupling operation may be elfected without excessive shock.

2. In a lateral angling car coupling, the combination of coupler heads having knuckles pivotally mounted therein, guard arms opposite said knuckles, sockets adjacent said knuckles, relatively high capacity bufiing means resiliently mounted in said knuckles, and relatively low capacity buffing means resiliently mounted in said guard arm, said last mentioned buffing means having cooperation respectively with said opposed sockets and said first mentioned buffing means being free of cooperation with the opposed couples when said coupler heads are in normal pulling position, said sockets affording limited vertical movement for the bufiing means received therein.

3. In a car coupling characterized by lateral angling, mated couplers comprising coupler heads, pivoted knuckles, sockets adjacent said knuckles, guard arms opposite said knuckles, buffing means resiliently mounted in said guard arms under relatively light compression, and buffing means mounted in said knuckles under relatively heavy compression, said buffing means under light compression being adapted to cooperate with the opposing sockets in the normal coupling operation, and both types of said buffing means being adapted to offer resistance to lateral angling, said sockets affording limited vertical movement of the buffing means received therein.

4. In a railway coupling characterized by lateral angling, the combination of mated coupler heads, knuckles pivoted therein, guard arms opposite said knuckles, means resiliently mounted in each of said guard arms and in each of said knuckles, and brackets laterally mounted on said heads adjacent said knuckles, both of said guard arm means being under compression when said couplers are in normal pulling position by engagement with the opposed brackets, said knuckl resilientmeans having relatively high capacity perun'it'of .travel as compared with said guard armiresilient means.

5. In a railway couplericharacterized by lateral angling,the combination of acoupler head, a resilient knucklepivoted therein, a guard arm comprising a projecting member and a'recesssed portion, a cavity in said guard arm, and means resiliently mounted in said cavity, said means normally extending outwardly of said projecting member and being retractable to a position coinciding substantially withsa'id recessed portion, said resiliently mounted meanshaving a relativelylight capacity per :unitof travel as compared with said resilient knuckle, whereby the coupling operation may be effected without excessive shocks.

6. In a car coupler, a coupler head, a pivoted resilient knuckle, a lug formedon said head laterally of said knuckle, a guard arm opposite said knuckle, said guard armhaving a recessed portion, a cavity in said guard arm, and a plunger resiliently mounted in said cavity under relatively light compression as compared with the comp-ression of said resilient knuckle and as compared with the forces employed in the normal coupling operation, said plunger normally extending beyond said guard arm and being retractable therein under buff substantially to the position of said recessed portion.

'7. In a car coupler, a coupler head, a pivoted resilient knuckle, a lug on said head laterally of said knuckle, a recessed portion on said lug, a guard arm opposite said knuckle, said guard arm having a recessed portion, a cavity in said guard arm, and a plunger resiliently mounted in said cavity under relatively light compression as compared with the compression of said resilient knuckle and as compared with the forces employed in the normal coupling operation, said plunger normally extending beyond said guard arm and being retractable therein under buff substantially to the position of said recessed portion.

8. In a coupling, the combination of coupler heads having pivoted knuckles, lugs mounted on said heads adjacent said knuckles, guard arms on said heads opposite said knuckles, and buffing means resiliently mounted in said knuckles and in said guard arms, said guard arm bufiing means having relatively light capacity springs as compared with said knuckle bufiing means, certain of said bufiing means having cooperation when said coupler heads are in normal pulling position and other of said bufiing means having cooperation under lateral angling,

9. In a car coupling the combination of coupler heads, knuckles pivoted therein, guard arms opposite said knuckles, means resiliently mounted in said knuckles, and other means resiliently mounted in said guard arms, both of said guard arm means having cooperation with the opposing coupler head When in normal pulling position and one of said guard arm means being free of cooperation therewith under certain conditions of lateral angling, said knuckle resilient means having relatively high capacity per unit of travel as compared with said guard arm resilient means.

10. In a lateral angling car coupling, the combination of coupler heads having knuckles pivotally mounted therein, guard arms opposite said knuckles, sockets adjacent said knuckles, relatively high capacity bufiing means resiliently mounted in said knuckles, and relatively low capacity bufi'lng means resiliently mounted in said guard arms, said last mentioned bufing means having cooperation respectively with said opposed sockets and said first mentioned bufling means being free of cooperation with the opposed coupiers when said coupler heads are in normal pulling position. a I

1 1. In a car coupling characterized by lateral angling, mated couplers comprising coupler heads, pivoted knuckles, sockets. adjacent said knuckles, guard arms opposite said knuckles, bufiing means resiliently mounted in said guard arms under relatively light compression, and bufiing means mounted in said knuckles under relatively heavy compression, sa-id buffing means under light compression being adapted to cooperate with the opposing sockets in the normal coupling operation, and both types of said bufling means being adapted to offer resistance to lateral angling.

12. In a car coupling, the combination of coupler heads having knuckles pivotally mounted therein and guard arms opposite said knuckles, relatively 'softbufiing means resiliently mounted in said guard arms, and other relatively still buff ing means resiliently mounted in said knuckles, said first mentioned buffing means having cooperation respectively with the mated couplers when said coupler heads are in normal pulling position and said last mentioned buffing means being free of cooperation therewith.

13. In a car coupling, the combination of coupler heads, knuckles pivoted therein, guard arms opposite said knuckles, means resiliently mounted in said knuckles, and other means resiliently mounted in said guard arms, said knuckle resilient means having relatively high capacity per unit of travel as compared with said guard arm resilient means, certain of said first and last mentioned means having cooperation with the opposing coupler head under conditions of maximum lateral angling.

14:. In a car coupling, mated couplers comprising coupler heads, pivoted knuckles, guard arms, buffing means resilienty mounted in said guard arms and said knuckles, said bufiing means in said knuckles having a relatively high capacity per unit of travel as compared with the relatively light capacity of said bufiing means in said guard arms, whereby the normal coupling operation may be efiected by compression of said relatively light capacity bufiing means and without substantial movement of said relatively high capacity bufiing means.

15. In a car coupling, mated couplers comprising coupler heads, pivoted resilient knuckles, guard arms opposite said knuckles, brackets adjacent said knuckles, and plungers resiliently mounted in said guard arms and said knuckles, the plungers in said guard arms being mounted to yield under relatively light compression and those in said knuckles to resist relatively heavy compression, whereby said guard arm plungers may have movement in the normal coupling operation and said knuckle plungers may resist such movement except under conditions of relatively heavy shock.

16. In a car coupling, mated couplers comprising coupler heads, pivoted knuckles, guard arms opposite said knuckles, brackets adjacent said knuckles, and plungers resiliently mounted in said guard arms and said knuckles, said knuckle plungers affording relatively high resistance to compression as compared to said guard arm plungers, said guard arm plungers being adapted to have engagement with mating couplers in the normal coupling operation, whereby said normal coupling operation may be efiected without excessive shock.

17. In a coupling characterized by lateral angling, mated couplers comprising coupler heads having pivoted knuckles and opposed guard arms, buffing means mounted in said guard arms under relatively light compression, and buffing means mounted in said knuckles under relatively heavy compression, said guard arm bufling means being adapted to engage and be compressed by the opposing coupler heads in the normal coupling operation, and certain of both types of buffing means being adapted to resist lateral angling.

18. In a car coupling, the combination of coupler heads having pivoted knuckles, guard arms, and buffing means resiliently mounted in said guard arms and said knuckles. said guard arm bufiing means having relatively light capacity as compared with said knuckle buffing means and being adapted to be compressed in the coupling operation, and said knuckle bufling means having a relatively high capacity and adapted to resist compression in the coupling operation.

19. In a car coupler having a pivoted knuckle and a guard arm, buffing means resiliently housed in said knuckle and in said guard arm, said means being retractile in their respective housings to positions within the normal contour of said parts, said knuckle resilient means having relatively high capacity per unit of travel as compared with said guard arm resilient means.

20. In a car coupler, a head, a knuckle pivoted therein, a guard arm, buffing means of relatively light capacity mounted in said guard arm and buffing means of relatively heavy capacity mounted in said knuckle, whereby the normal coupling operation may be effected by compression of said relatively light; buffing means without substantial movement of said relatively heavy capacity buffing means.

EDMUND P. KINN'E. FRANK H. KAYLER.

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