US2921540A - Stabilized spring suspension means for railway cars - Google Patents

Description

Jan. 19, 1960 R. c. WILLIAMS 2,921,540

STABILIZED SPRING SUSPENSION MEANS FOR RAILWAY CARS Filed March 11, 1957 4 Sheets-Sheet 1 f1 g l 24 IO 32 23 27 r I 7 l r I I l L4 I 24a- 25:, g a6 X'Q 4-8 m 2| 4 26a. S

52 as 6 i {g 2! l l 55 54 "T /e g 12 39 ab .50 25m. 1 so \x\ INVENTOR. RAY C. WILUAMS Jan. 19, 1960 R. c. WILLIAMS 2,921,540

STABILIZED SPRING SUSPENSION MEANS FOR RAILWAY CARS Filed March 11. 1957 4 Sheets-Sheet 2 INVENTOk. RAY C. WILUAMS Jan. 19, 1960 R. c. WILLIAMS STABILIZED SPRING SUSPENSION MEANS FOR RAILWAY CARS Filed March 11, 1957 4 Sheets-Sheet 3 uvwszvron. RAY C. WILLIAMS Jan. 19, 1960 R. c. WILLIAMS 2,921,540

STABILIZED SPRINI SUSPENSION MEANS FOR RAILWAY CARS Filed March 11. 1957 4 Sheets-Sheet 4* United States Patent STABILIZED SPRING SUSPENSION MEANS FOR RAILWAY CARS Ray C. Williams, Chicago, Ill., assignor to Standard Car {ruck Company, Chicago, 111., a corporation of New ersey Application March 11, 1957, Serial No. 645,244

12 Claims. (Cl. 105-224) The improved stabilized spring suspension of the present invention has been designed for use primarily in connection with the running gear of relatively short railway cars of the four-wheel variety. In this type of running gear each journaled portion of the wheel axle is supported for vertical movement in a separate frame unit secured direct to the car body at opposite sides thereof. Each frame unit or pedestal seats on the top of a group of load supporting springs positioned above the axle journal.

While the invention is disclosed herein in connection with separate pedestal frame elements secured to the car body, it will be obvious, as the disclosure progresses, that the frame elements at each side of a car may be rigidly connected with each other by means other than the car body and thereby provide a four-wheel truck suitable for use with longer cars.

Heretofore, considerable difficulty has been experienced in providing running gear of the above type with suitable means for damping the undulations of the load springs and thereby avoid the build-up therein of undulations of objectionable amplitudes. These difliculties have been due primarily to the use of constructions which involve locating the load springs and their associated damping means a substantial distance above the axle journal and in failure to balance the application of damping force at opposite sides of the journal. As a consequence, the load springs and the stabilizing means of such prior structures have a pronounced tendency to develop objectionable arcuate oscillations about the journal as an axis and thereby fail to provide efiicient damping of the spring movements. Such oscillating of the parts also produces localized wear on the friction surfaces of the wedges.

The present invention overcomes the above noted limitations by the provision of cooperating arrangements and constructions whereby relatively long load springs may be used and whereby friction means in the form of Wedges may be so positioned that the horizontal forces or reaction of the friction wedges are substantially in line with the horizontal center line of the pressure area of contact of the journal bearing and the element mounted thereon for supporting said springs and their associated stabilizing means.

According to the present invention, each side frame unit of the running gear seats, as a pedestal, on the top of a group of load springs positioned above an axial journal, the said springs being supported on a so-called saddle which has bearing contact with the major portion of the upper half of a journal bearing, preferably, though not necessarily, a roller type bearing. The forward and aft portions of the saddle are formed with surfaces which slope in downwardly diverging directions at opposite sides of the axle journal with their extremities extending to regionsat or below the plane of the transverse horizontal axis of said journal. The friction wedges are supported on the sloping surfaces-of said saddle in aposi- Patented Jan. 19, 1960 2 tion to bear frictionally against opposing guide and friction faces of the truck pedestaL.

Each friction wedge member is formed with a curvilinear wedging surface thereon which cooperates with the sloping surface on which it is supported. The said curvilinear surface has a straight co-linear contact with the said sloping surface of the saddle member along a line extending transversely of the wedge and intersecting the extended vertical axis of a stabilizing spring positioned to exert pressure on the wedge member, whereby the direction of force applied to each wedge member is aligned with the axis of the stabilizing spring and thereby avoids development of eccentric or unbalanced forces on the wedge. By such an arrangement, the friction wedges bear flat against opposed friction faces on the pedestal and are at all times in stable equilibrium with respect to the journal saddle, whereby a more consistent damping action and longer wear life of the friction faces will be attained. Furthermore, the line contact between the curvilinear faces of the friction wedges and the cooperating wedging faces on the journal saddle (see point 56 on Fig. 7) are so disposed, as previously indicated, that the horizontal forces or reaction of the friction wedges pass through the contact area between the journal bearing and the saddle at a location between the center of the journal and the top of the journal bearing and thereby removes any tendency which these forces have, in the absence of the above balanced arrangement, to exert forces on the saddle tending to oscillate it about the journal hearing.

A further improved feature of the present invention is the provision of cooperating friction surfaces on each pedestal and on the associated journal saddle member, the arrangement being such as to embrace a wide area of contact both vertically and horizontally so as to provide, in effect, a relatively long moment arm which serves as an anti-torque reaction member to resist oscillation of the journal saddle and the springs and the stabilizing wedges supported thereon.

A further limitation that is attendant upon the use of present day pedestal type running gear arises from the necessity of permitting lateral motion of the journal boxes, journal bearing assemblies or other anti-friction load spring supporting means associated with the j ournaled portions of the wheel axle whereby relative motion may take place between the axle and car body in order that the wheels will hold to the rails. The provision of sufficient tolerance between the pedestal and the journal saddle in which the axle is journaled to allow for a certain amount of relative lateral motion between the journal saddle and an associated pedestal, to accommodate limited lateral swaying of the car body relative the axle journals and also permit limited lengthwise oscillation of the axle, has a tendency to promote objectionable harmonics in these movements unless they are retarded.

The present invention overcomes this last noted limitation by the provision of an effective damping means between the pedestal and load spring support which is effective against vertical oscillations of the car body and also lateral displacement in both directions and operates at widely separated regions of the pedestal to assimilate the sidewise thrust thereof and reduce harmonic swaying of the car body to a minimum.

A still further feature of the present invention, in a stabilizing mechanism of the character set forth above, is to provide friction plates on the inside surfaces of the pedestal and cooperating wear pads on the journal saddle, the plates and pads being attached to the respective members with which they are associated.

Other advantages of the invention, not at this time enumerated, will become readily apparent as the following description ensues.

In the accompanying drawings forming a part of this specification, a preferred embodiment of the invention has been shown.

In these drawings:

Fig. 1 is a vertical longitudinal half-section view of the running gear of a railway car incorporating the lateral motion and stabilizing instrumentalities of the present invention.

Fig. 2 is a sectional view taken substantially along the line 2-2 of Fig. 1.

Fig. 3 is an end elevational view of the structure shown in Figs. 1 and 2.

Fig. 4 is an enlarged fragmentary perspective view of a bumper construction employed in connection with the present invention.

Fig. 5 is a sectional view taken on line 55 of Fig. 1.

Fig. 6 is a fragmentary sectional view taken on line 6-6 of Fig. l; and Fig. 7 is a diagrammatic view illustrating the curvature of a friction surface utilized in connection with the present invention.

Referring now to the drawings and particularly Figs. 1 and 2 thereof: The improved running gear and spring suspension contemplates the provision of four units 10 of identical construction for accommodating four wheels 11 and the journaled portions 12 of the wheel axles 13 associated with said wheels. Inasmuch as the four units 10 are of identical construction, the present disclosure is confined to only one such unit 10, it being understood that the said units 10 are arranged in pairs at each side of a car and are secured thereto by suitable means. Each unit is composed of a plurality of elements which may be described briefly in the overall assembly as comprising a side frame 14, a saddle structure 15 adapted to be supported on a bearing assembly 16 supported on the axle journal 12 and having a sliding interlocked engagement with the side frame 14. A pair of concentrically arranged load springs 17 and 18 are interposed between the central portion of said saddle 15 and the side frame 14, whereby the load of the car is transmitted through the side frame 14, load springs 17, 18, and saddle 15 to the bearing 16 and the axle journal 12. Preferably, the inner load spring 18 is shorter than the outer spring 17, so that the inner spring 18 will function as a load supporting element only when the load is sufficient to compress the outer spring to the level of the upper end of the inner spring.

The general construction also includes a means designated as a whole by the reference numeral 20 for stabilizing the undulations of the load springs 17, 18 and thereby prevent the build-up of oscillatory movements of objectional amplitudes. It will be sufficient at this time to indicate that the stabilizing mechanism includes a pair of friction wedges 21, 21 carried by the saddle member 15, the Wedges being pressed by stabilizing springs 22 into frictional engagement with portions of the frame 14 at opposite sides of the journal 12. The improved constructions of the Wedges 21, 21 and the manner in which they cooperate with other elements of the assembly as a Whole will be made apparent by the detailed descriptions of the several elements of the assembled structure.

Pedestal structure Each side frame or pedestal unit 14 is a casting of inverted U-form and includes an upper portion 23 and a pair of depending guide columns 25, 26. The said upper portion 23 is of inverted channel form and is secured to the car body, for example a side sill 24 by means of bolt and nut assemblies 24a. The depending guide columns 25, 26 are of channel construction, for the purpose of rigidity, and have opposed inner faces to which wear plates 25a, 26a are loosely applied, the latter being held in place by parapet lugs 27 and wear plates 37 and 41 and thereby avoid the development of latent stresses which are frequently present in wear plates that are attached to the columns by conventional welds.

In order to further rigidify the guide columns 25, 26

and prevent spreading thereof their lower ends are connected together by means of a tie bar 28. The tie bar is secured to the said columns by means of bolts 29 and by upturned end portions 30 of the bar, the latter portions being hooked over the lower, ends of the columns. The upper portion of each pedestal includes depending cylindrical retaining lugs 31 and 32, the frame of which holds the upper end of the stabilizing spring 22 in proper position and the latter serves as a retaining means for the load springs 17 and 18.

Journal saddle Referring now to the structure and functions of the journal saddle 15: It is of geenral X-confi'guration, as viewed in side elevation, including a semi-cylindrical central portion 33 which seats on the journal bearing assembly 16, a pair of upwardly and outwardly diverging arms 34, 35 having wear pads 36, 37 engaging the wear plates 25a, 26a on the guide columns 25, 26, downwardly diverging arms 38, 39 having wear pads 40, 41 loosely supported by parapet lugs similar to lugs 48 and engaging said wear plates 25a, 26a, and lateral buffers designated generally by the reference numerals 42 and 43 (Figs. 1 and 5); the said buffers functioning in combination with the said stabilizing means 21 to damp lateral movements of the pedestal 10 and the journal saddle 15 relative to each other.

The central portion 33 of the journal saddle 15 includes stepped retaining seats 44, 45 for the lower ends of the load springs 17, 18 and outer and inner reinforcing webs 46, 47 (Figs. 1 and S) which follow the contour of the load spring 17 (as viewed in plan in Fig. 5) and merge into the arms 34, 35 to provide them with spaced apart side webs 34a, 34b and 35a, 35b, respectively. These spaced apart side webs of the arms 34, 35 permits the stabilizing springs 22, 22 to extend through the said arms, as shown best in the cross sectioned portions of Figs. 1 and 5. The outer ends of the arms are formed with parapet lugs 48 for retaining the wear pads 36, 37 in floating relation to said arms 34, 35.

The lower arms 38, 39 of the journal saddle are formed in their forward and aft faces with pockets 49, 50 for receiving the friction wedges 21, 21 for bearing frictionally against the wear plates 25a, 26a. Each wedge pocket includes a downwardly inclined bottom wall 51 on which the associated friction wedge 21 is supported. The wedge member 21 is generally triangmlar in vertical cross-section as viewed in Fig. 1 and has an outer friction face 52 for hearing against the adjacent wear plate 25a or 26a. The opposite side of the Wedge is provided with a wedge face 53 which is of curvilinear contour for the bottom of the wedge to substantially the top thereof. The top wall 54 of the wedge is formed with a raised circular boss 55 in alignment with the boss 31 formed on the pedestal top wall 23 and the two bosses serve to center thereon the stabilizer spring 22, the latter being of considerably lighter gauge than the load springs 17 and 18.

Stabilizing devices of the general character described thus far wherein wedge-shaped friction shoes are arranged in such operative relationship to a car pedestal, or more commonly to a car bolster, that when the bolster moves downwardly under the influence of a load against the action of the load-supporting springs, the shoes are pressed into tightened frictional engagement with suitable surfaces on the truck frame to dampen the succeeding upward surge of the bolster, are known in the art. According to the present invention, however, the character of the saddle member, particularly the slope of the friction surfaces thereon, as well as the specific curvilinear contour of the wedge face of the wedge members 21 alford improved operating characteristics and reliability of operation, all in a manner that will now be set forth in detail.

As shown in Fig. 1, and more particularly in the exlggerated diagrammatic illustration of Fig. 7, the curvilineal wedge face of each wedge member 21 is formed with arcuate side surface regions A, A, each of which has a relatively long radius of curvature. The two surfaces A, A merge with a medial arcuate surface B having a shorter radius of curvature, thus providing a crown portion which engages the inclined surface 5 1 of the sadle along a horizontal line of contact 56 which is located on the vertical longitudinal axis XX of the stabilizer spring 22.

The slope angle of the inclined bottom of each wedge receiving pocket 49, 50 is such that the horizontal vectorial components of force applied to the saddle member as a whole by the adjacent friction wedge member 21 are well below the top or zenith of said journal bearing. This slope angle of the bottom surfaces of the wedge pockets may be varied in different installations to accommodate differing stabilizer spring pressures, car body weights and contemplated loads, and coeflicients of friction between the various surfaces which have mutual rubbing contact.

Since the cylindrical crown portion B in the medial regions of the wedge surface 53 (see Fig. 5) makes a line contact with the inclined bottom 51 of the pocket, phenomena which ordinarily would cause angular turning movement of the wedge in the pocket has no such effect on the wedge and the latter is allowed only the desired vertical component of motion. Additionally, the crown portion tends to concentrate the developed frictional forces in a limited medial region so that the wedge offers more resistance to displacement in either direction when exerting its intended stabilizing effect. Since the line of contact 56 between the surfaces 53 and 51 lies on the vertical axis XX coinciding with the longitudinal axis of the stabilizer spring 22, eccentric forces on the wedge are eliminated and a more consistent damping action and longer wear life of the friction surfaces will be attained.

Referring now to the portions 42, 43: the journal saddle which functions as bufiers to damp and finally 'to limit lateral movements of the pedestal and the journal saddle relative to each other. The said buffers include a series of four wings 42a, 42b and 43a, 43b which are offset outwardly from opposite sides of the journal saddle 15 (see Figs. l, 5 and 6) and overlap the outer and inner side faces, respectively, of the guide columns 25, 26. On the inner face of each of the offset wings is arranged a resilient bumper construction comprising a plate 57 welded to its associated wing portion of the journal saddle, a bumper element 58 is secured to the plate 57 by an intervening resilient element 59, for example a block of rubber. The rubber block 59 is bonded or otherwise secured to both elements 57, 58 so. that the latter can move toward and away from the former. The opposite ends of said bumper plate are turned laterally to overlap and slidably embrace laterally turned end portions 61, 62 of the plate 57. These ends are formed with return bends 63, 64 which serve as stops for limiting the compression of the rubber block.

The bumper plates 58 are normally spaced outwardly a selected distance from the side faces of the guide columns 25, 26. This spaced relationship is normally 4 inch at each side of the guide column, thereby permitting relative lateral movement of the guide columns 25, 26 and the journal saddle 15 for the maximum distance of V2 inch, which movement is restrained only by the frictioned pressure of the wedges against the wear plates a, 26a. At the extremity of such lateral movement one or the other of the bumper plates 58 engage an adjacent side face of a guide column of the pedestal. There is capacity for a further lateral movement of approximately A inch, but this movement is resisted by the conjoint action of the friction wedges 21 and the compression of the resilient block. It will be also noted that these combined forces serve to damp any vertical movements of the pedestal guide columns 25, 26 relative to the journal saddle 15 which may occur during the contact of the bumper plate 58 with a guide column.

Insofar as the stabilizing action of the various stabilizer springs 22 and friction wedges 21 is concerned, downward movement of the pedestals 10, which are attached directly to the car body, will place the load spring groups 17, 18 under compression in the normal manner while the stabilizer springs 21 will be placed under increased compression to force the pairs of wedge members 21 downwardly in their respective pockets 49, 50 and into tighter wedging relation with respect to the vertical wear plates 25a, 26a and the inclined wedging surfaces 51 on the saddle members 15. By their frictional engagement against wear plates 25a, 26a and reacting against inclined surfaces 51, the wedge members exert a damping action on the downward movement of the pedestal, the action being more effective by virtue of the existence of the cylindrical crown portion B and the curved side surfaces A, A, since the latter provide more clearance for wear and adjustments of the wedges relative to the saddle. The broad vertical spread of the upper and lower wear pads carried at the ends of the arms of the saddle 15 when considered collectively restrains the saddle casting from tilting about the axis of the wheel axle so that objectionable oscillations of a vibratory nature are broken up. The wide horizontal spread of the said wear pads restrain the saddle members against twisting movements so that the saddle will have no tendency to leave its seat on the journal bearing assembly 16. Also the flat line bearing 56 of the wedges against the inclined surfaces 5-1 in the wedge pockets prevents twisting movements of the wedges about a vertical axis. Alignment of the crown portions 56 with the longitudinal vertical axes XX of the stabilizing springs 22 eliminates the application of eccentric forces on the wedges and the pressure applied on the various rubbing wear surfaces will be evenly distributed and result in a smooth efiicient damping action with longer life of the friction parts, all in a manner that has been made clear during the description of the stabilizing mechanism.

I claim:

1. In a stabilized spring suspension for a railway car pedestal type truck, a pedestal structure having a top portion and spaced apart guide columns depending therefrom provided with opposed friction faces, an axle journal and bearing therefor positioned between said guide columns, a saddle element mounted on said journal bearing and having portions slidably engaging said guide columns to maintain the axle journal centered between said columns, a load supporting spring seated on said journal bearing saddle and engaging the pedestal to resiliently support the latter for movement relative to said saddle, and friction means for damping the movements of said pedestal relative tosaid saddle comprising spring pressed wedge elements positioned for slidable wedging engagement between said saddle and said opposed friction faces of said guide members; the said saddle being formed with a central area for contacting and partially embracing said journal bearing and said wedges being so positioned that their center line of horizontal thrust passes through the axle journal.

2. The combination structure as defined in claim 1 characterized in that the journal bearing saddle slidably engages the opposed friction faces of said guide columns at locations above and below the transverse center of the axle journal and further characterized in that said friction Wedges engage the opposed friction faces of the guide coiurnns at locations intermediate the surfaces of the saddle having said sliding engagement with said opposed friction faces of the guide columns.

3. A combination structure as defined in claim 2 characterized in that the forward and aft portions of said journal bearing saddle are provided with pockets for receiving said friction wedges, the said pockets being formed with inclined bottom walls for wedging engagement with adjacent faces of said friction wedges.

4. The combination structure defined in claim 3 characterized in that each friction wedge has a flat face for frictional engagement with an adjacent guide column, and an inclined face on its opposite side provided with a crowned portion engaging the said inclined bottom wall of its associated pocket and presenting to said inclined bottom wall a line contact transversely of the wedge to prevent turning of the wedge about a vertical axis.

5. In a stabilized spring suspension for a railway car pedestal type truck, a pedestal structure having a top portion and spaced apart guide columns depending therefrom provided with opposed friction faces, an axle journal and bearing therefor positioned between said guide columns, a journal bearing saddle mounted on said hearing and having portions slidably engaging said guide columns to maintain the axle journal centered between said columns, a load spring group seated on said saddle and engaging the pedestal to resiliently support the latter for movement relative to said saddle, friction wedges positioned for wedging engagement between the forward and aft portions of said saddle and the adjacent friction faces of said columns, spring means interposed between the said wedges and the upper portion of said pedestal for effecting said wedging engagement of the wedges and for maintaining the wedges in frictional engagement with said columns, bumpers on the saddle and overlying the inner and outer side faces of said guide columns for limiting lateral movements of the pedestal and the saddle with respect to each other; the said bumpers being normally spaced from the side faces of said guide columns and are adapted to move into engagement therewith during lateral movements of the pedestal relative to the saddle and the friction wedges carried thereby, whereby the said friction wedges function by their frictional engagement with said guide columns to damp the said lateral movements.

6. The combination structure as defined in claim 5 characterized in that each bumper comprises inner and outer steel plates having interposed therebetween re silient means cooperating with said wedges to resist a portion of the lateral movements of the said columns relative to the saddle.

7. The combination structure as defined in claim 6 characterized in that the said resilient means associated with each said bumper is an elastomeric pad bonded to opposed sides of said steel plates.

8. The combination structure as defined in claim 7 characterized by the provision of a stop for limiting the compression of said elastomeric pad.

9. In a stabilized spring suspension for a railway pedestal type truck, a pedestal structure having a top portion and spaced apart guide columns depending therefrom provided with opposed inner faces, wear plates loosely seating against said opposed faces, parapet retaining lugs formed on said guide columns and overlying the edges of said wear plates, an axle journal and a bearing therefor positioned between said guide columns, a saddle element mounted on said bearing and having portions slidably engaging said wear plates to maintain the latter in their operative positions and also having inclined walls intermediate the portions slidably engaging said wear plates, a load spring seated on said saddle and engaging the pedestal to resiliently support the latter for vertical and lateral movements relative to said saddle, friction wedges carried on the inclined walls of the saddle and having wedging engagement between said inclined walls and the wear plates on said columns, and spring means interposed between said wedges and the upper portion of said pedestal and cooperating with said inclined walls to press said wedges against said wear plates.

10. A combination structure as defined in claim 9 characterized in that the said saddle is provided with spaced apart portions located above and below the horizontal axis respectively of the journal bearing and provided with wear pads, supported in floating relation to the saddle and slidably engaging said wear plates.

11. A combination structure as defined in claim 10 characterized in that the said wear pads are retained loosely in their operative position on the saddle by means of parapet lugs formed on the saddle and engaging the edges of the wear pads.

12. In a stabilized car truck comprising a frame member formed with spaced apart vertically extending guide columns and a guided member supported between said columns in vertically sliding engagement therewith and provided with foreward and aft pockets therein having inclined wall portions, of means for damping the movements of said frame member and said guided member relative to each other comprising wedges positioned in said pockets for frictional engagement with said-guide columns; each wedge member being formed with a cylindrically crowned face for wedging contact with the inclined wall portions of its associated pocket, and helical springs interposed between said wedges and a portion of the frame to press the crowned faces of the wedges into wedging contact with the inclined walls of said pockets, each spring being so positioned relative to its associated wedge that the extended longitudinal axis of the spring bisects the crown face of its associated wedge at the point of its bearing against the inclined wall of the pocket containing such wedge.

References Cited in the file of this patent UNITED STATES PATENTS 2,327,151 Cottrell Aug. 17, 1943 2,355,450 Leese Aug. 8, 1944 2,497,460 Leese Feb. 14, 1950

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