US3796166A

US3796166A - Railway locomotive suspension stabilizing

Info

Publication number: US3796166A
Application number: US00218352A
Authority: US
Inventors: D Wilmot
Original assignee: General Steel Industries Inc
Current assignee: GSI ENGINEERING Inc A CORP OF; Lukens General Industries Inc; General Steel Industries Inc
Priority date: 1972-01-17
Filing date: 1972-01-17
Publication date: 1974-03-12
Anticipated expiration: 1991-03-12
Also published as: CA948037A; ZA723343B; BE788855A; GB1340153A; AR199190A1; ES408052A1; BR7208716D0

Abstract

A stabilizing railway locomotive suspension includes a pair of swivel trucks having frames supported from the axles by a primary suspension and supporting the underframe by a secondary suspension. The trucks are connected to the locomotive underframe by longitudinally inclined links so that axle-to-axle load transference in each truck is minimized, and to eliminate traction load-responsive variations in coupler height, even with a soft secondary suspension, the links at each side of the locomotive are arranged so that their axial projections intersect in the region of the line of draft.

Description

UnitedStates atent Wilmot at. 12, 1974 [54] RAILWAY LOCOMOTIVE SUSPENSION 324,831 8/1885 Gerhardt 105/199 R STABILIZING 2,954,746 10/1960 Cripe 105/199 R X 3,547,046 12/1970 Lich 105/199 R [75] Inventor: Douglas G. K. Wilmot, Creve v t I I Coeur Primary ExaminerGerald M. Forlenza [73] Assignee: General Steel Industries, lnc., St. Assistant Examinerl-loward Beltran Louis, Mo. Attorney, Agent, or Firm-F. Travers Burgess [22] Filed: Jan. 17, 1972' [52] US. Cl. 105/199 R, 105/135, 105/182 R, l

v 105 /2OO ax es by a primary suspension and supportmg the un- [51] [m Cl B6 3/04 B61f5/16 B6lf5/22 derframe by a secondary suspension. The trucks are [58] Fie'ld 'gg' losilgg R 135 136 connected to the locomotive underframe by longitudi- 05/182 nally inclined links so that axle-to-axle load transference in each truck is minimized, and to eliminate trac- Y tion load-responsive variations in coupler height, even [56] References Cited with a soft secondary suspension, the links at each side UNITED STATES PATENTS of the locomotive are arranged so that their axial pro 3,563,185 2/1971 Wilmot et a1, 105/199 R jections intersect in the region of the line of draft,

665,382 1/1901 Carnahan 105/199 R R21,987 12/1941 Green 105/200 11 Claims, 5 Drawing Figures 7 6 Q Q 59 65 65 59 c; 47 a l 5/2 a 7 e55 /t\ 17 Q M Appl. No.: 218,352

[5 7] ABSTRACT A stabilizing railway locomotive suspension includes a pair of swivel trucks having frames supported from the PATENWMR 1 2 m4 SHEEY 3 [IF 3 RAILWAY LOCOMOTIVE SUSPENSION STABILIZING BACKGROUND OF THE INVENTION:

1. Field of the Invention The invention relates to railway rolling stock and consists in a locomotive suspension arranged to minimize weight transference from axle to axle in each truck and eliminates tipping of the locomotive underframe longitudinally and consequentvariations in coupler height responsive to traction load.

2. The Prior Art The closest approach in the prior art to the present invention, of which I am aware, is the truck arrangement of my U.S. Pat. No. 3,563,185, which utilizes single inclined draft links at each side of the truck to provide an effective rail-level traction point. The patented trucks have a stiff secondary suspension, rather than the desirable soft secondary suspension of the present invention, and hence the problem of longitudinal tipping of the locomotive body due to the action of draft forces is not severe in the patented construction. There is accordingly no teaching in this prior patent, or in any other prior art of which I am aware, of an arrangement of the draft links and cooperating truck structure to' eliminate such tipping when a soft secondary suspension is provided.

SUMMARY OF THE INVENTION The invention provides a railway locomotive suspension by which axle-to-axle load transference in each truck is minimized, good riding qualities are achieved, and tendencies of the locomotive body to tip longitudinally responsive to traction load, with consequent variations in coupler height, are eliminated.

It is an object of the invention to achieve the above results with a simple construction and arrangement of the component parts.

It is a further object to achieve both the minimization of axle-to-axle load transference and the elimination of longitudinal body tilt by the arrangement of inclined longitudinal draft links connecting the trucks to the underframe. A

BRIEF DESCRIPTION OF THE DRAWINGS:

FIG. 1 is a side elevational view of a locomotive embodying the invention;

FIG. 2 is a plan view of a truck forming part of the locomotive iilustrated in FIG. 1.

FIG. 3 is a side elevational view of the truck illustrated in FIG. 2.

FIG. 4 is a transverse vertical sectional view along lines 44 of FIGS. 2 and 3.

FIG. 5 is a loading diagram of the locomotive shown in FIG. 1.

DETAILED DESCRIPTION:

A locomotive 1 has an elongated body 3 resiliently supported near its ends on a pair of swivel trucks 5A and 5B supported on track rails R. At its ends, body 3 mounts draft couplers 6 at a predetermined height above track rails R for mating engagement with similar couplers on other rolling stock.

Each of the

trucks

5A and 58 has a pair of transverse axles 7 and 8 spaced apart longitudinally of the truck and each rigidly mounting a pair of transversely spaced gauged railway flanged wheels 9 resting on track rails R. At their ends, outboard of wheels 9, axles 7 and 8 are rotatably received in journal boxes 11.

A rigid truck frame, preferably of one-piece cast steel construction, comprises transversely spaced longitudinally extending side members 13 positioned transversely outboard of wheels 9 and rigidly connected to each other by transverse center transom 15 intermediateaxles 7 and 8, and end transoms 17 located longitudinally outboard, respectively, of axles 7 and 8. Frame side members 13 are vertically apertured adjacent journal boxes 11 to form pedestal jaws I9, and journal boxes 11 are vertically slidably received in jaws 19, whereby the axles are maintained transverse of the truck frame. Upright primary springs 23, seated on journal boxes 11, underlyingly support frame side members. 13 in the conventional manner and effectively oppose tipping of the truck frame longitudinally with respect to the track by reason of their spacing longitudinally of the truck.

Longitudinally intermediate the axles each of the frame side members is depressed to a low level as at 25, and center transom 15 is located at the same level.

For permitting swivel between the truck and supported vehicle body 3, center transom 15 is formed at its center with a vertical cylindrical recess 32 and frame side members are each formed intermediate their ends with a pair of longitudinally spaced upwardly facing flat horizontal bearing surfaces 29.

A transverse bolster 31 is formed with a depending cylindrical boss 33 pivotally received within recess 32. Bolster 31 is parallel to and slightly spaced vertically from the upper surface of center transom 15 and extends outwardly of the truck frame over frame side members 13. For supporting bolster 31 on the truck frame and for stabilizing the truck frame and bolster against tipping longitudinally of the truck with respect to each other, the latter is provided, in the region in which it passes over the truck frame side members 13, with forwardly and rearwardly extending wings 35, formed with downwardly facing flat horizontal bearing surfaces 37 slidably seated on upwardly facing frame side member bearing surfaces 29, the substantial distance between

bearings

29, 37 at each side of the bolster lengthwise of the truck thus providing an arm opposing tendencies of the truck frame and bolster to tip longitudinally of the truck with respect to each other. The transverse and longitudinal spacing of

bearing surfaces

29, 37 prevents tilting of the bolster and truck frame about transverse and longitudinal axes with respect to each other.

At its ends transversely outboard of truck frame side members 13, bolster 31 is formed with upwardly open spring pockets 39. Toperrnit transverse movement of the vehicle underframe U relative to the truck, a sandwich device comprising a pair of horizontal rubber pads 41 bounded by and interleaved with metal plates 43 is seated in each pocket 39 and supports an upwardly open spring seat 45. Spring seats 45 in turn support pairs of upright primary metallic coil springs 47, which directly support body 3 through spring caps 49.

Body 3 is capable of vertical movement relative to bolster 31 through vertical deflection of springs 47 and of lateral movement relative to bolster 31 through shear deflection in springs 47 and pads 41.

For limiting the lateral movement, body 3 is formed with depending stops 50 inwardly of spring caps 49 and bolster 31 has opposing upstanding stop brackets 52 spaced inwardly from stops 50 and mounting elastomeric bumpers 54.

To dampen such vertical and lateral movements, at

its ends the bolster is connected to body 3 by upright snubbers 51 and intermediate its ends is connected to body 3 by transverse horizontal snubbers 53.

For transmitting longitudinal forces from the truck to the underframe at track level, whereby to eliminate any vertical moment arm through which tractive forces generated at rail level by the engagement of the wheels and rails, might act to transfer load from one axle to the other, the outwardly protruding ends of bolster 31 are bent downwardly longitudinally of the truck, as at 55, in the same direction as each other, and terminate at a level sufficiently above the rail to conform to clearance limitations and at a distance somewhat offset longitudinally of the truck from the transverse center plane thereof. Bolster end portions 55 terminate in transverse webs 57 whose planes are inclined slightly longitudinally of the truck and traction links 59, which may be of similar construction to the anchor links disclosed in V. F. Green Reissue US. Pat. No. 21,987, are connected at 58 to webs 57 and extend therefrom longitudinally of the truck and upwardly to a similar connec tion at 61 to a transverse slightly inclined web 63 of a bracket 65 depending from body 3.

Connections

58 and 61 are constructed to provide limited universal pivoting of the links. The inclination of traction links 59 longitudinally of the truck is such that their axial projections intersect the transverse vertical plane, indicated by line C-C in FIG, 1, through the load center of the truck, at a very low level, preferably at rail level. With this arrangement the effective point of connection of the traction links to the truck structure is at the intersection of the traction link projections with the transverse vertical central plane of the truck just as though the links were attached to the truck structure at this point, and thus draft forces generated by the engagement of the wheels and rail surface are transmitted from the truck to the body at the same level, so as to eliminate any vertical moment arm about which load transference from axle to axle would otherwise occur.

The truck is powered by a pair of electric traction motors M journaled'respectively on axles 7 and 8 and supported by their noses on opposite sides of center transom 15. Gear boxes G transmit driving torque from motors M to the associated axles.

To eliminate substantial tipping of locomotive body 3 about a transverse axis resulting from the application of traction forces from the trucks to the body, which on conventionally suspended locomotives act through a vertical moment arm from the rail level to coupler level to raise the forward end of the locomotive body and lower the rear end, trucks A and 5B are positioned as shown in FIG. 1, with traction links 59 of both trucks extending longitudinally inboard of the locomotive toward each other, such that their axial projections intersect in the region of the line of draft, preferably at a point x, a predetermined distance y above the line of draft, the center line of couplers 6.

It will be evident that if the traction link projections intersect at the same level as the line of draft, the opposing vertical components of the traction link forces will cancel each other out, as the rear truck link pushes up on the body and the front truck link pulls down, and since the horizontal components will be in horizontal alignment with the couplers, there will be no moment on the locomotive body with respect to the line of draft, and hence no tendency to deflect the secondary suspension responsive to traction load. Such a connection would not affect truck-to-truck weight transfer (caused by the traction moment on the complete locomotive, and resulting in unequal deflection of the primary spring systems of the two trucks), but would affect only the moment on the locomotive body and hence the deflection of secondary springs 47.

The preferred arrangement wherein the axial projections of the traction links intersect a predetermined distance above the line of draft, provides a moment on the locomotive body, the arm of which is the distance y, which will deflect the secondary springs 47 by increasing the compression of the front truck secondary springs 47 and reducing the compression on the rear truck secondary springs 47. The distance y is dependent on the spring rates and if accurately determined, will provide a moment on the locomotive body which will deflect the secondary springs 47 sufficiently to compensate precisely for the deflection of the primary springs of the respective trucks.

The value of the distance y may be expressed by the following equation:

where b height of coupler center from rail K,, primary spring rate for an entire truck K, secondary spring rate for an entire truck In the development of the above equation for the value of y, if

a distance between truck centers a secondary spring deflection d, primary spring deflection P, total force applied to all secondary springs of a truck P,, total force applied to all primary springs of a truck T traction force to achieve the object of the invention, i.e., to deflect the secondary springs of each truck sufficiently to compensate precisely for the traction moment responsive deflection of the primary springs, it is necessary to make d, z d

Solving first for d,,: cl P /K Since P a T' b (moments acting on the entire locomotive) i: 'r om d, T b/a K Solving for d,: d, P /K Since P,,- a T- y (moments acting on the locomotive body) P T y/a d, T y/a K and since a z d T y/a K, T b/a K, therefore It will be understood that if, for mechanical or other reasons, the traction links 59 cannot be arranged so that their axial projections intersect precisely at point x, an intersection near this point will in most cases be sufficient to prevent excessive coupler height variation.

The details of the locomotive suspension disclosed herein may be modified substantially without departing from the spirit of the invention and the exclusive use of all modifications as come within the scope of the appended claims is contemplated.

I claim:

1. In a railway locomotive, a pair of trucks'spaced apart longitudinally, each of said trucks comprising a pair of powered longitudinally spaced wheeled axles, primary springs carried by said axles, truck structure comprising truck frames supported on said primary springs, secondary springs carried by said truck structure, said secondary springs being substantially vertically yieldable under load, a body supported by said secondary springs of both trucks for substantial vertical movement thereon with respect to said truck structure, vertical axis pivotal connections between said respective truck frames and said body, said body mounting draft coupling means on at least one ofits ends, longitudinally extending traction links pivotally connected at their one ends to the respective truck structures and extending solely longitudinally inboard and upwardly from their connections to the respective truck structure, said traction links being pivotally connected at their other ends to said body such that their axial projections intersect the transverse vertical planes through the load centers oftheir respective trucks at a level substantially lower than their connections to said truck structure and intersect each other in the region of the line of draft of the locomotive, said traction links being functional in both tension and compression and forming the sole longitudinal force transmitting connection said truck divided by the total spring rate of the primary springs of each said truck.

4. In a railway locomotive according to claim 2, the distance of the intersection of the axial projections of said traction links above the line of draft being such that the moment of the traction force and this distance on the body tilts the body sufficiently to cause the deflection of the secondary springs of each truck to compensate for the deflection of the primary springs of the respective trucks caused by the moment of the traction force and the coupler height on the entire locomotive.-

structures being to the ends of the respective bolsters.

6. In a railway locomotive according to claim 5, each said bolster having end portions outboard of the respective truck frame and extending downwardly and inboard longitudinally of the locomotive, said traction links being connected respectively to the extremities of said respective bolster end portions.

7. In a railway locomotive according to claim 6, said primary springs being supported directly from the axles and directly supporting the respective truck frame.

8. In a railway locomotive according to claim 5, each said truck frame comprising a pair of longitudinally extending transversely spaced side members and a transverse transom located intermediate said axles and rigidly connecting said side members, said vertical axis pivotal connection comprising cooperating cylindrical bearing elements at the centers of said bolster and of said transom.

9. In a railway locomotive truck according to claim 8, opposed horizontal bearing surfaces on said bolster and truck frame spaced apart longitudinally of the truck a substantial distance whereby to prevent tilting of the truck frame relative to the respective bolster longitudinally of the truck.

10. In a railway locomotive according to claim 8, said secondary springs comprising upright metal coil springs.

11. In a railway locomotive according'to claim 10, said secondary springs comprising flat horizontal pad devices in series with said coil springs whereby to accommodate substantial lateral as well as vertical movement between said body and said bolster.

Claims

1. In a railway locomotive, a pair of trucks spaced apart longitudinally, each of said trucks comprising a pair of powered longitudinally spaced wheeled axles, primary springs carried by said axles, truck structure comprising truck frames supported on said primary springs, secondary springs carried by said truck structure, said secondary springs being substantially vertically yieldable under load, a body supported by said secondary springs of both trucks for substantial vertical movement thereon with respect to said truck structure, vertical axis pivotal connections between said respective truck frames and said body, said body mounting draft coupling means on at least one of its ends, longitudinally extending traction links pivotally connected at their one ends to the respective truck structures and extending solely longitudinally inboard and upwardly from their connections to the respective truck structure, said traction links being pivotally connected at their other ends to said body such that their axial projections intersect the transverse vertical planes through the load centers of their respective trucks at a level substantially lower than their connections to said truck structure and intersect each other in the region of the line of draft of the locomotive, said traction links being functional in both tension and compression and forming the sole longitudinal force transmitting connection betweEn said trucks and said body.

2. In a railway locomotive according to claim 1, the intersection of said traction links being above the line of draft.

3. In a railway locomotive according to claim 2, the intersection of the axial projections of said traction links above the line of draft being approximately equal to the product of the coupler height and the total spring rate of the secondary springs of a truck divided by the total spring rate of the primary springs of a truck.

4. In a railway locomotive according to claim 2, the distance of the intersection of the axial projections of said traction links above the line of draft being such that the moment of the traction force and this distance on the body tilts the body sufficiently to cause the deflection of the secondary springs of each truck to compensate for the deflection of the primary springs of the respective trucks caused by the moment of the traction force and the coupler height on the entire locomotive.

5. In a railway locomotive according to claim 1, each said truck structure comprising a transverse bolster supported on the respective truck frame to pivot about said vertical axis pivotal connection, said secondary springs of each truck being carried on the ends of the respective bolster and directly supporting said body, there being a pair of said traction links for each truck, said traction link connections to the respective truck structures being to the ends of the respective bolsters.

11. In a railway locomotive according to claim 10, said secondary springs comprising flat horizontal pad devices in series with said coil springs whereby to accommodate substantial lateral as well as vertical movement between said body and said bolster.