US2504113A

US2504113A - Underframe for vehicles, fspecially railway cars

Info

Publication number: US2504113A
Application number: US588866A
Authority: US
Inventors: Walter B Dean
Original assignee: Budd Co
Current assignee: ThyssenKrupp Budd Co
Priority date: 1945-04-17
Filing date: 1945-04-17
Publication date: 1950-04-18
Anticipated expiration: 1967-04-18
Also published as: GB641347A; FR925694A

Description

W. B. DEAN April 1s, 195o UNDERFRAME FOR VEHICLES, ESPECIALLY RAILWAY C ARS Filed April 17. 1945 7 Sheets-Sheet 1 INVENTOR Waler B. Dean. BY f Ku-74 ATTORNEY W. B. DEAN April 18 1950 UNDERFRAME FOR VEHICLES, ESPECIALLY RAILWAY CARS Filed April 17, 1945 7 Sheets-Sheet 2 YB Dean M7: ATTORNEY INV ENTOR Walt W. B. DEAN April 18, 1950 UNDERFRAHE FOR VEHICLES, ESPECIALLY RAILWAY CARS '7 Sheets-Sheet 3 Filed April 17. 1945 v w @y mm D M Y l l l l l 1 l 1 l l I l i.. M R mm? m EH T ma A 1w hunmmummmumulnmmmm April 1s, 195o 2,504,113

UNDERF'RANE FOR VEHICLES, `IISPECII..I.Y RAILWAY CARS w. B. DEAN '7 Sheets-Sheet 4 Filed April 17. 1945 Ilrllellxldllwllnlzllu g z t Y INVENTO D M ATTORNEY April 18, 1950 w, B DEAN 2,504,113

UNDERFRAME FOR VEHICLES, ESPECIALLY RAILWAY CARS Filed April 17. 1945 7 Sheets-Sht 5 P KG. 9

Walter @7pm ATTORNEY W. B. DEAN April 1s, 195o UNDERF'RAME' FOR VEHICLES, ESPECIALLY RAILWAY CARS Filed April 1v. 1945 7 Sheets-Sheet 6 lNvl-:N'roR Walter B. Dean 7? M# ATTORNEY W. B. DEAN April 18, 1950 UNDERFRAME FOR VEHICLES, ESPECIALLY RAILWAY CARS Filed April 17. -1945 7 Sheets-Sheet 7 ATTORNEY lNVENTOR Walter B. Dea.

Patented Apr. 18, 1950 UNDERFRAME FOB VEHICLES. FSPEGIALLY RAILWAY CARS Walter B. Dean. Nal-berth, Pa., assigner to The Budd Company, Philadelphia, Pa., a corporation of Pennsyl Application April 17, 1945, Serial No. 588,886 zo claims. (ci. s-416) The invention relates to an underframe for vehicles such as railway cars and more particularly to an underframe of the type having a center sill provided with cross members for supporting the flooring and for connection with the end and side-:walls u n l A`primaryobjet, sill for velii underframes which combines minimum weight with the ability to withstand most severe stresses and to counteract the well known tendency of center sills to bend upwardly in the middle together with the entire body when subject to severe longitudinal compression.

Another object of th'nventlonisanend lmdilf; frame adapted for the transmission of the stresses from the coupler and buffer into the adjoining portion of the body`center sill without undue stress concentrations and with such distribution of the stresses contributing to the achievement of the above outlined main object.

Still further objects of the invention have to do with the simple and efcient connection between the center sill and the remainder of the underframe structure, with the connection of the latter to certain of the upstanding body walls, and with the construction and arrangement of the underframe members adjoining the center sill.

With the aforesaid and other objects in View. a main feature of the invention resides in a center sill which, contrary to the customary structures, is asymmetrically constructed in regard to a horizontal longitudinal plane passing through' the geometric center line of the sill and which has a concentration of strength in its lower portion so that the neutral axis lies closer to the underside than to the upper side of the sill.

Another feature of the invention consists in an end underframe construction having means for directing the stresses exerted on the end underframe by the buffer and coupler in a downwardly inclined direction and thereby toward vthe strong lower portion of the adjoining body center sill.

The invention is especially adapted, though by no means restricted, for use in combination with the copending applications Serial No. 580,646, Body for Vehicles, Especially Rail Cars" of the inventor and Serial No. 580,647, Body Construction, Especially for Rail Cars, of R. J. Theriault, both filed on March 2, 1945. The body center sill may also be used in connection with or as part of the end underframe structure disclosed in the simultaneously led application Serial No. 588,760 of the inventor and Albert G. Dean, on End Underframe Construction for Vehicles, Especially Railway Cars.

The outlined and other objects, advantages and features of the invention will be more clearly and more easily understood from the embodiment illustrated in the attached drawing and described in the following.

In the drawing:

small scale planvview of the main Fig. 2 is a fragmentary plan view of the complete underframe on a larger scale;

Fig. f3 is a fragmentary side elevation partly in` section along line 3-3 of Fig. 2;

Fig. 4 is a fragmentary plan view of one of the end underframe structures with the adjoining the body center sill, the same structure being sho n in the preceding figures yet on a smaller scale and with less deails;

Fig. 5 is a side elevation of the structure shown in Fig. 4;

Fig. 6 is a longitudinal section along line 6-8 of Fig. 4;

Fig. 7 is a fragmentary end elevation of one of the end sills viewed in the direction of the arrows on lines 'I-'l of Fig. 2 but on a larger scale;

Fig. 8 is an inside elevation of the structure shown in Fig. 7, and a section along line 8-8 of Fig. 2 through the underframe structures on the scale of Fig. 7;

Fig. 9 is a fragmentary end elevation of the transverse sill at the vestibule partition wall and a section substantially along line 9-9 of Fig. 2 lllrough the end frame center sill on the scale of Figs. 10 and "11 are fragmentary sections through the center sill of the end frame and through adjoining underframe parts substantially along lines II-III and II--I I, respectively. of Fig. 2 and on the scale of Fig. 7;

Fig. 12 is a fragmentary end elevation of the bolster beam and a section through the end frame and body center sills substantially along lines I2--l2 of Fig. 2l on the scale of the preceding figures:

Fig. 13 is a large scale fragmentary longitudinal section through the non-vestibule end of the underframe substantially along line I3-I3 of Figs. 2 and 14;

Fig. 14 is a fragmentary plan view of the region surrounded by line I4 in Fig. 2 on the scale of Fig. 13;

Fig. 15 is a fragmentary section corresponding to and on the scale of Fig. 13 yet of the vestibule end and taken substantially along line l5-l5 of Fig. 2;

Fig. 16 is a large scale section through one of 3 the bolster beams and the adjoining floor and a side elevation of the adjoining center sill portions, the section being taken substantially along lines I6-I6 of Fig. 2;

Fig. 17 is a fragmentary end elevation of one of the cross bearers or needle beams and a, section through adaoining portions of the center sill. side sili and floor substantially along line I1-I1 of Fig. 2 on a similar scale as the preceding ngures;

Fig. 18 is a fragmentary transverse section on the scale of Fig. 17 through the middle portion of the underframe in a region between a bolster beam and a cross bearer, tne section being taken substantially along hnes I8| 8 of Figs. 2 and 19; and l Fig. 19 vis a section through one of the cross bearers and adjoining floor portions substantially along lines lei-I9 of Figs. 2, 17 and 18 and on the scale of the latter.

The underframe illustrated in the drawing comprises: a body center sill I; end underframes 2 and 3, each provided with a center sill portion 4 and a bolster beam

end cross bearers

6 and 1; a vestibule partition cross bearer 6; and intermediate body cross bearers or needle beams 6. The general arrangement of these members is clearly illustrated in Fig. 1, and theu skeleton framework formed by them is structurally connected with a transversely reinforced sheet metal floor designated as a whole by the numeral III in F' .2.

igt should be understood that the entire construction is substantially symmetrical with respect to the longitudinal vertical center plane, and that the end underframes are substantially identical with the exception of details incidental to the fact that the car has, as customary, a vestibule and entrance wells at one end. called hereinafter the vestibule end, but is free from such wells at the other end, called hereinafter the non-vestibule end. The description or illustration of one side of the body will serve,

therefore. as description for the other side, and the gures and description of either -one of the end underframes will in most cases serve for disclosing the construction of both end underframes except where the diilerences are specincally outlined.

'I'he construction of the end underframes is shown in detail in Figs. 4 through 16. At ilrst. only the unitary structure composed of the center sill portion 4 and the bolster beam 5 as well as the collision or bumper member II will be described, leaving the description of adjoining portions of the floor and of the cross members to a later part of the specification.

Each end underframe is welded together, preferably by electric arc welding, from a plurality oi' steel plates cut to appropriate size, with the exception of a, few complicatedly shaped parts auch as the end member II which are preferably castings connected by welding to the remainder of the end underframe.

The center sill portion 4 of each end underframe comprises a pair of transversely spaced vertical walls I2 reinforced along their upper and lower margins by outwardly directed iianges I3 and I4. These walls with their ilanges may be constituted each by a rolled U-section-see Fig. 1l. From the region of lateral brackets I5 serving for the attachment of the partition wall'cross beam 3, to be described later on, the lower portions of the walls diverge outwardly toward the end of the frame these diverging portions of the side walls and flanges are designated. respectively. I6 and I1 (Figures 4 to 6, 8, 13 and 15) 'lhe lower marginal portions of the vertical walls I2 and I6 as well as the adjoining portions of the flanges I4 and I1 are cut away over part of their length and repiaced by a welded-in angle section piece I3 of heavier gauge, the flange I9 of this angle section constituting a continuation of the nanges I4 and I1 (Figures 5, 6, 9, 13 and l5) The brackets I5 are welded to the walls and flanges Il, I6, I3 and I9 and the connection to the nange I3 is reinforced by corner gussets 'tu (Figures 4, 5 and 13).

At a short distance outboard of the brackets I5 each side wail I2 and its top nange I3 are continuedby an angle section member having a vertical arm or wall 2I and horizontal arm or flange 22. The inboard ends of these members are 1nterconnected by a vertical transverse web 23 and their lower margins are connected to a horlzontal plate 24 which has its lateral margins? welded to the upper margins of the diverging walls I6 (Figures 4, 6, 8 and 13). On the outside of the walls I2 and I6, the plate 24 is continued inboard by nns 25 which extend across and some distance inboard beyond the brackets I5 (Figures 5, 13 and 15). A transverse angle section piece has the ends o f its

arms

26 and 21 welded to the upper and lower margins of the plate 23 so that its apex is on about the level of the flanges I3. The arm 26 is wider than the arm 21 and its marginal portions interconnect and form continuations of the flanges I3 and 22 (Figures 4, 5, 13 and l5). The space between the arm 26, the fins 25, the brackets I5 and the wall 23 is filled out by small plates 28 arranged in the planes of walls I2 and 2I (Figures 5, 13 and 15) Besides, the triangular structure formed by the

arms

26, 21 and the plate 23 is centrally reinforced by a welded-in triangular gusset 29 (Figure 4).

The end casting I I is a hollow section structure having its top wall 3II arranged in line with the flanges 22 and its bottom wall 3| arranged on the level of the plate 24 (Figures 5 and 6). Interior

transverse webs

32 and 33 are respectively arranged in continuation of the vertical walls I6 and 2I (Figures 4, 7 and 8). The lower portion of the webs 32 are continued by inner vertical wall portions of a bowv or yoke 34 (Figures 6 to 8) serving for the support of the coupler (not shown). A pair of vertical horns 35 project beyond the top surface of the casting II and may consist of separately manufactured lpieces welded to the casting proper along the lines 36. See Figures 3 to 8 and 13 to 15. These horns 35 serve as connecting means and reinforcements for and as parts of the collision beams or posts (not shown). The end casting I I is welded, such as by arc welding, to the walls I6, 2I, 24 and to the ilanges I4, 22 in plane 31 where the two structures meet (Figures 4 to 6). Brackets 38 (Figures 4 and 5) serve for the support of buffer side stems (not shown).

The top wall 26 of the

angle section member

26, 21 is continued by a web or plate 33 which slopes downwardly in the direction toward the bolster beam 5 and has its side margins welded to the side walls I2. The inboard end of the plate 39 is welded to a horizontal plate 40 lwhich interconnects the wall I2 at the level of the flanges I4 and extends in both directions slightly beyond two transverse longitudinally spaced vertical webs or bulkheads 4I inserted between and welded to the walls I 2 and the plate 40. See Figures 4, 6, 9, 10, 11 and 16.

Inserted between and welded to the walls I2 and the meeting margins of the webs 25. 21 and 39 is a transverse bulkhead 42 which is reinforced by an inboard directed flange 43. the lower portions of which are connected to a pair of castings or forgings 44, one on each side (Figures 6 and 9). These members 44 which are likewise welded to the walls I2 and the reinforcing angles I8, serves as guides and abutments for the draft and bumng gear (not shown). A second bulkhead 45 is arranged inboard of the bulkhead 42 and is likewise welded to the inclined web 33, the vertical walls I2, the members Il and to a horizontal plate 43 which latter is welded along its lateral margins to the members I8 and the walls I2 and arranged at about the level of the anges I4. The bulkhead 45 serves as the second abutment for the draft and fbuiilng gear.v See Figures 4. 6 and 10.

The side walls I2 with their flanges I3 and I4 extend inboard a short distance beyond the bolster beam 5. As shown in Figures 5, 6 and 16.

the upper portions of the walls I2 with their flanges I3 end at a considerable distance outboard of the lower portions with their anges I4 which latter constitute on each side a rearwar extension or horn designated by the numeral 41. These extensions of the side walls and their flanges are for the attachment of the body center sill I which will be described later on.

The webs or bulkheads 4I are arranged in line with the side walls 48 of the bolster beam 5 (Figures 12 and 16). The bottom walls 49 of the bolster halves have their inner margins secured to the flanges I4 and are consequently interconnected by the latter and the plate 49. The upper walls 50 of the bolster beam halves are attached to the anges I3 and continued and interconnected by a top plate 5I inserted between the walls I2 and of about the same longitudinal extent as the bottom plate 40. ASee Figures 4. 6, 12 and 16.

The box sectional bolster beams are interiorly reinforced on each side by a web or bulkhead 52 and the connections between the side Walls 48 and the top flanges I3 as well as the connection between the bottom wall 49 and the bottom flanges I4 are reinforced by welded-in

corner gussets

53 and 54, respectively. The middle portions of the bolster beams are upwardly and outwardly inclined and their side walls and bottom walls are provided with large openings 55 for saving of weight and for giving access for the welding operations. See Figures 4, 5, l2 and 16.

The outer ends of the bolster beams, as shown in Figures 4 to 6 and 12, are offset and provided with an upstanding plate 55 for fitting into and connection with the side sills 51 and the adjoining side walls (not shown). The formation of the ends of the bolster beams and their connections to the side sills and to the side walls is more fully disclosed in the application Serial No. 580,647 of Raymond J. Theriault, referred to hereinbefore.

From the foregoing description of the end underframes it will have become apparent that an extremely sturdy and strong structure is achieved which, for all practical purposes, can be considered as a one-piece structure inasmuch as its component parts are firmly welded together by electric arc or similar welding.

Each end underframe structure is furthermore reinforced by a cover plate 58 for the draft gear pocket, which plate is secured by a great number of bolts 56' to the flanges I6 of the reinforcing members I8 and extends in outboard direction beyond plate or web 45.

The axes of the stresses exerted by the buffer gear and by the draft gear (not shown) are indicated respectively, by the dot-an'd-dash lines 59 and 56 in Figure 6. These stresses are transferred into the walls I2 and, by means of the bulkheads 42 and 45 in collaboration with the inclined web 39 downwardly into the lower portion of the end underframe near the bolster beam. y

The purpose of this downward direction of stresses will become apparent from the following description of the construction of the body center sill I.

The body center sill I, as shown in Figures 12 and 16 to 19, consists mainly of two transversely spaced vertical walls 5I and a bottom wall 52. The side walls are channel sections, each having vertical web 53 and upper and lower marginal outwardly directed

flanges

54 and 55. The webs 53 are stiffened each by an inwardly projecting channel section groove 55. The .bottom wall 52 consists of two

super-imposed plates

51 and 68. The plate 51 has marginal upwardly directed flanges 59 which overlap and are secured, such as by electric spot welding, to the webs 53 of the side walls below the channels 55. The lower plate 58 underlies and is secured, such as by electric spot welding. to the arms or flanges 55 of the side walls and the web of plate 51. Both

plates

51 and 58 are provided with a`n upwardly projecting stiffening channel section portion 10.

Disregarding the sheet metal flooring I0, which will be described later on, the body center sill I presents an open-top box or hollow section with a heavily reinforced bottom wall 52. The consequence 'of this construction is, as shown in Figure 6, that the horizontal neutral plane of the sill, indicated by the dot-and-dash line 1I, lies far below the horizontal plane, indicated by the dot-and-dash line 12, passing through the geometric center of the sill. In the illustrated embodiment, the neutral plane 1I is at about t/g of the height of the center sill. In a practical embodiment of a full size car the height 13 of the sill is 15.4" and the distance 14 from the neutral axis 1I is located at 10.82" from the top, that is, from the upper surface of the flanges 54.

The ends of the body center sill I lt telescop- ,ingly between the inboard extensions of the side walls I2 and over the outsides of the top and bot'- tom flanges I3 and I4 of the end underframes. The webs 53 and the bottom anges 55 with the marginal portions. of the reinforcing plate 68 are connected by

rivets

15 and 15 ,to the overlapped portions of the end frames. The connection between the upper flanges I3 and 54 will be described after the description of the flooring. The underside of the bottom plate 55 is overlapped at each end by a center bearing casting 11 which is connected to the plate 56 and to the flanges I t and 55 by rivets 18. See Figures 4 to 6, 12 and 16. The center plate serves, as usual, for the connection between the underframe and the trucks (not shown).

The transverse bearers or needle beams 9, best shown in Figures 17 and 19, are of closed box sectional construction having longitudinally spaced side walls 19 provided with iianges 60 along their lower margins, a bottom plate or web 8l interconnecting and secured to the flanges 86, and a channel section closing member 83 on each side of the center sill bridging by its web 85 the space between the walls 19 and secured by its groans arms l to the insides `oi' the latter. The side walls end at the outside of the center sill and are secured to the webs 0I thereof by flanges 00. 'I'he bottom plate 0I extends across the center sill from one side of the body to the other and is secured to the ilanges 0I and the bottom plate 00 thereof. The intersection of the cross bearer and the center sill is further reinforced by a pair of channel section members 01 which are secured by their bottom walls to the margins oi the plate 0 and thereby to the ilanges 00 and in their middle portion to the plates 61, 60 and the flanges 00.

Shear webs or bulkheads 00 are inserted between the upper portions of the center sill side walls 03 in line with the side walls 'Il of the cross bearer and are secured to the center sill side walls 63 by their marginal flanges 09 (Figures 17 and 19). The space between the two plates 00 and between the inner ends of the cover plates 03 is bridged by a channel section member 90 which is similar in cross section and arrangement to the cover plates 03. It may be noted here that the cover plates 03 and 90 are not considered main stress transmitting elements of the structure but that the upper chord of the cross bearer is mainly formed by parts of the adjoining floor structure which will be described shortly hereafter.

'I'he outer ends of the cross bearers are each closed by a vertical plate 9| which extends upwardly beyond the top surface thereof and the walls of the cross bearers are offset so as to flt into the side sills 51 (Figure 17). This end construction and the connections of the cross bearer with the side sills and with the side walls of the body (not shown) are more fully disclosed and form the subject matter of the application Serial No. 580,647, Raymond J. Theriault, repeatedly rei'erred to hereinbefore.

The iloor between the cross bearers and between the cross bearers and the bolster beams is constituted by a multitude of transversely arranged channel section members 92 having their bottom walls 93 arranged in one plane and their side walls 94 abutting and connected with each other by spot welding and provided with inturned marginal anges 95. A few of the floor pans, as at 90, face downwardly. See Figures 2, 3, 12, 16 and 19. 'I'he pans 90 have their side walls connected with the adjoining side walls of the pans 92 and their bottom walls and anges arranged respectively in the planes of the flanges and bottom walls of the floor pans 92. The connection between the upturned and downturned floor pans 92 and 96 is additionally reinforced by weldedon strips 91 (Figure, 16). The purpose of the open-bottom floor pans is to make room for pipe lines and the like.

At some locations the side walls of adjacent floor pans are slightly spaced from each other, see at 98 in Fig. 3; and have their top flanges or walls connected by strips or bands similar to the strips 91, this spacing may serve for the insertion between the juxtaposed side walls of downwardly extending braces as suspension means of accessories (the braces and accessories are not illustrated) The bottom walls 93 of the open-top floor pans 92 and the flanges 95 of the open-bottom floor pans 90 rest on the top flanges 64 of the vcenter sill and are secured to the latter together with reinforcing strips 99, preferably by electric spot welding, Figs. 16, 18 and 19. Where the :door pans overlap the inward portions of the end underirames, rivets |00 pass through the reinforcing strips 99, the bottom wall 03 of the door pans, the anges 04 of the body center sill and the top flanges I3 of the end underframe, as clearly shown in Figs. 12 and 16.

The floor pans 92 adjoining the cross bearers I have their side walls 0I secured to the side walls 10 of the cross bearer and are reinforced by channel section members 0| which nest into the channel formed by the bottom wall Il, the side wall 94 and the flange 90 of the oor pan. The members |0| are also firmly secured to the floor pan and thereby to the cross bearer side walls 19. See Figures 17 vand 19. These floor pans with their reinforcements I0| extend over the entire width of the body underframe and constitute the main top chord members of the cross bearers rather than the cover members Il, 00 within the cross bearer, a fact briefly mentioned hereinbefore.

The outboard floor pans 92 abut with their outboard side walls 94. the inboard side walls I0 of the bolster beams and are secured thereto. For the latter purpose, a reinforcing band |0I is spot welded to 'the inside of the end side walls 94 and both are plug welded to the bolster wall 48. See Figures 12 and 16.

The regions between the bolster beams 0 and the vestibule partition bearer 0 or the brackets Il at the non-vestibule end are bridged by Z-section transverse members |02 having one of their arms |03 overlappingly secured to each other and by rivets |04 and reinforcing strips |05 to the top flanges I3 of the center sill portions of the end underframes whereas their webs |06 are upwardly directed and have their top arms |01 arranged in one plane with the top flanges of the channel section floor pans 92. The members |02 adjoining the bolster beams have a second upturned arm |00 (Figure 16) reinforced by a strip |0I' and abutting and secured to the outboard wall 40 of the bolster beam in the same manner as described in the preceding paragraph for the inboard side of the bolster beam. The outboard member |02, Fig. 13, has its top ilange turned inboard rather than in the outboard direction as the other members |02.

The members |02 are preferably of substantially heavier gauge than the iioor pans 92, 0l so as to materially reinforce the end portions of the car which have to carry heavy equipment such as air conditioning equipment, toilet facilities, etc. The ratio in thickness may be for instance about 2 to 1. No effort has been made to show this difference of gauge in the drawing.

At the non-vestibule end of the underframe (Figures 8, 13 and 14) four short open-top floor pans |09 are inserted between the web or arm |00 of the last member |02 and the inboard vertical wall |0 of the end cross bearer 1. The inner ends of these short floor pans |09 are supported on each side by the outwardly extending horizontal arm ||I of Z-section plates |I2, the other arm III of which rests on top and is secured to the respective iiange 22 of the end underframe. The ends of the plates ||2 are secured respectively to the outboard member |02 and the inboard part |I4 of the top wall of the cross bearer 1. The connection between member I|2 and the floor pans is further strengthened by strips III' secured to the outer margin of the arm ||3 and the l inner ends of the top flanges of the iioor pans.

Each cross bearer 1 consists in addition to the walls I I0, III, just described, ot an outer top wall portion IIS, an outer wall |I0 and a bottom wall |11, all of which members are overlappingly se- 4cured together so as to form a closed box sectional structure (Figures 13 to 15). 'Ihe inner ends of the walls ||4 to |I1 are reinforced by plates and channel sections ||8 and 'I I3 spot welded to the insides of these walls and arc welded at to the end wall |2| of the casting The top wall portion I I4 and the inner wall I I0 overlap the top wall 30 and the inner wall |22 of the casting and are secured thereto by plug welds |23, |24 (Figures 8 and 14) A transverse reinforcing and attachment strip |25 of angle section is secured to the top wall portion ||4.

The construction of the sill 8 at the vestibule end is identical with the construction of the sill 1,

except that is has no floor pans |03 secured thereto, so that the same reference numerals are applied to sill 6 in Figure 15 and no further description thereof is required.

The partition 8 has a wall |28 (Figures 9 and 15) together with its vertical hat section reinforcements |21 riveted to the brackets I5 and is secured by welding to the outboard web |28 of the last oor member |02. The wall |28 is slightly higher than the webs |06 of the adjoining floor members and it has its marginal'flange |23 turned inboard and connected with a Z-section strip |30.

Two hat sections |3| are arranged longitudinally at both sides of the longitudinal middle plane of the body, and two other angle section Ymembers |32 are arranged close to the side margins of the underframe. 'I'he members l3| and |32 extend from the end sill 1 and its strip |25 (Figures 8 and 13) to the strip |30 at the partition structure 8 and are secured by their flanges or one of their arms respectively to the tops of the l() employed. One such modified end underframe construction is disclosed in the, before mentioned, simultaneously nled application Serial No. 588,760 of the present applicant and Albert G. Dean on End underframe construction for vehicles, especially railway cars."

It is pointed out in the beginning of this description that the end underframes are mostly formed of steel plates are welded together and by an end casting Il. The remainder pf the disclosed construction is formed vpractically throughout of sheet metal parts connected with each other by spot welding. The arc welds are conventionally diagrammatically indicated. The spot welds also are indicated at many places by asterisks or, in sectional views, by heavy black dots at the interfaces. The sheet metal of the construction is preferably of the high tensile type and more specifically cold rolled stainless steel.

With the full illustration and description of one embodiment of the invention in mind, the main feature of the invention, mentioned hereinbefore, will be easily understood.

floor pans as well as on the wall portions ||4 and |30 of the

transverse members

1 and 8. The floor boards (not shown) extend between the members |3| and between the members |3|, |32.

The opening between the walls 2| near the outboard ends of each end underframe is closed, as shown in Figures 7 and 8, by a removable plate |33 so as to give access to the chamber formed by the walls 2 I, the transverse web 23 and the horizontal wall 24 and serving for housing the buifer gear not shown) The center stem and the side stems of the buffer gear project through the openings |34 and |35, respectively, of the end casting The longitudinal members |38 bolted to the walls 2| serve for guiding the middle part of the buffer gear.

The outer ends of the floor pans 92, 96, |02 and |09 fit telescopingly into and are secured to the walls of the upper channel section portion of the side sills 51 (Figures 8 and 11) as is more fully disclosed in the hereinbefore cited applications Serial No. 580,646 of the present applicant and -Serial,No. 580,647 of Raymond J. Theriault. The

side walls 51 ext'end uninterruptedly between and are secured to the non-vestibule end sill 1 and the partition wall structure 8 (Figures 1 and 2). The regions between the one bolster beam 5 and the end sill 1 and between the other bolster beam 5 and the partition structure 8 are reinforced by downwardly facing channel sections |31 which have their bottom walls secured to the undersides of the floor pans, their outer walls to the side sills 51 and their inner walls to an angle section strip |38. The ends of these members |31 are secured to the respective bolster beams 5 and

cross bearers

1 and 8. See Figures 1, 8, l1 and 12.

While the body center sill is illustrated and described in combination with substantially identical arc welded end underframes 2 and 3, different end underframes on one or both ends may be structure.

The tendency of center sills to bnd upwardly together with the remainder of the body under compression loads may be attributed to the fact that the loads are mostly applied near the underside of the body by the buffer and coupler, see lines 59 and 60 (Figure 6), causing compression of the center sill and the lower portion of the body whereas the upper portion of the body (not shown) is subjected to much less compression forces and is consequently less foreshortened. The obvious consequence of this condition is that the body will arch upwardly in its middle portion. Customarily center sills which have their neutral plane approximately coincided with the horizontal transverse plane passing through the geometric center of the sill have no remedying eil'ect on this situation.

The new center sill construction, however, with its great concentration of strength in the lower portion of the sill effectively counteracts the tendency to arch or bend upwardly, because it requires much more strength to compress the lower portion of the sill and thereby to foreshorten it than to compress the upper portion thereof.

In this connection it is worth mentioning that the floor pans, though forming main transverse structural elements for the entire vunderframe and also between the center sill side walls, are believed to have, partly on account of the transversely extending reinforcing grooves |39 (Figures 16 and 18), no great strength in longitudinal direction so that the center sill is indeed practically an open-top box or hollow section The bottom chord of this structure which is formed by the plates 61, 68 and the flanges 65 has many times the strength of the top chord constituted `merely by the anges 64 (Figure 18).

It will now also be easily understood how important it is that the stresses originating at the buffer and the bufilng gear are transmitted, withoutabrupt change in direction, downwardly in inboard direction which is partly achieved by the inclined webs 39 and the bulkheads, bottom reinforcements and other transverse members such as 24, 26, 21 secured to the side walls I2 of the end underframes. In this same connection it will be understood why the connection between the end underframes and the lower portion of the body center sill is so much stronger and includes a greater number of rivets than theconnection near the upper margin of the body center sill.

The foregoing description and the attached drawing of one `embodiment is by way of illustration only and is not intended to limit the scope of the invention as deilned by the attached claims. the invention is susceptible of many modifications and of adaptations to specific body constructions without departing from its spirit and basic principles, and` certain features of the invention, such as for instance the body sill or the end underframe construetions maybe used advantageously independently of other features.

What is claimed is:

l. In a vehicle body, an underframe having a longitudinal center sill of such asymmetrical construction that its horizontal neutral plane is a considerable distance below the middle of the sills height, which sill is structurally connected substantially throughout its length along its upper side to a shear panel structure of great transverse but little longitudinal stiffness.

2. In a vehicle underframe: such as for railway car bodies, a longitudinalcenter sill having two transversely spaced side walls and a bottom wall but being substantially open at the top so that its neutral plane is closer to the sill underside than to its upper side, and a transversely reinforced panel closing the open top and structurally connected to' the upper margins of the sills side walls substantially throughout their length, the structure having great strength against transverse stresses and counteracting the tendency of the sill and of the remainder of the body connected therewith to buckle upwardly under heavy compression stresses.

3. Underframe for vehicle bodies such as railway car bodies comprising between its wheel supported points a hollow section open-top longitudinal center sill and a transversely reinforced panel, constituting the floor supporting structure, structurally connected to the upper margins of the sill's side walls and extending across the mouth and over at least a major part of the length of the sill.

4. Underframe center sill for vehicles such as railway cars consisting mainly of two heavy gauge channel section transversely spaced longitudinally extending side wall members, of a heavy gauge bottom wall structure extending between and connected to the lower marginal arms of the side wall members, and of alight gauge top wall structurally interconnecting and interbracing said side walls, so that the closed box-sectional structure formed by said walls has its horizontal neutral plane substantially below the middle of its height.

5. A center sill for vehicles of open-top hollow section having laterally facing transversely spaced U-section side walls and a first bottom wall member overlappingly attached to and interconnecting the lower arms of the side walls, in combination with a generally U-section second bottom wall member extending between and having its arms secured to the lower portions of the webs of the side walls and its web secured to the middle portion of said first bottom wall member.

6. In an underframe for vehicle bodies, such as railway car bodies, a longitudinal center sill having supporting points widely spaced from each other in the longitudinal direction of the sill, said sill comprising two transversely spaced longitu- 12 tending bottom wall structurally interconnecting the side walls and a transversely stiff but longitu dinally weak structure extending across the mouth of the sill and structurally interconnecting the upper margins oi' the side walls.

7. End underframe for vehicle bodies especially railway cars comprising a center sill portion having transversely spaced upstanding side walls interconnected by transverse webs, one of said webs extending from a point near the upper side and the outboard end of the center sill portion at a gentle slope in inboard direction to a point near the underside of the center sill 'portion so as to direct compression forces exerted on the center sill near its outboard end toward the underside of the sill.

8. End underframe for railway cars comprising a center sill portion and a bolster beam integrally connected to the center sill portion at a distance inboard from the latters outboard end, said center sill portion being provided with means for directing longitudinal impact stresses exerted on the center sill in a downwardly inclined direction toward a point of the center sill near the bolsterbeam.

9. End underframe for railway cars comprising a hollow section center sill having transversely spaced side walls interconnected by transverse walls and webs, the outboard end of said sill being widened and provided with a top plate for the accommodation of a buli'er suspension, said top plate near the outboard end of the center sill merging into a downwardly and inboard sloping web extending between and secured to the side walls and approaching the underside of the side walls near the attachment zone of a bolster beam.

l0. Center sill construction for vehicles provided at its end portions with means for the attachment of bumng and draft gear, in combination with a middle portion adjoining the end portions, which middle portion has its horizontal neutral plane arranged below its geometric longitudinal middle line, and means on said end portions adapted for directing at least a large part of the stresses exerted by the bufllng and draft gear without abrupt change in direction downwardly and inboard into the lower part of the middle portion of the center sill.

11. In an underframe for railway car bodies and the like, a center sill having a thick walled end portion and a thin walled sheet metal middle portion, said middle portion having such asymmetrical construction that its horizontal neutral plane is below the middle of the height of this portion, the inboard end of the end portion overlapping and being secured to said middle portion for a greater length near the bottom of the sill than near its top.

l2. In an underframe for railway car bodies and the like, a center sill having a thick walled end portion and a thin walled sheet metal middle portion, said middle portion having such asymmetrical construction that its horizontal neutral plane is below the middle of its height, the inboard end of said end portion of the center sill extending at the bottom a considerable distance further inboard than the top and overlapping the outboard end of the middle portion of the sill, and connecting means between the overlapping portions arranged near the top and bottom of the sill and4 extending over a greater length near the bottom.

13. Center sill structure for railway cars and the like comprising at least one vertical wall prodinally extending side walls, alongitudinally ex- 7s vided with a laterally projecting web sloping 13 downwardly in inboard direction, bufiing and draft gear abutments arranged beneath said transverse sloping web and secured thereto as Well as to said vertical wall.

14. In an end center sill for underframes of railway cars and similar vehicles, longitudinally extending and transversely spaced side walls interconnected by an inboard and downwardly sloping web, a transverse bulkhead arranged beneath said web and secured to the same as well as to said side walls, a bottom plate interconnecting the lower margins of the side walls in the region of and secured to said bulkhead, said side walls, web and bulkhead constituting together a pocket for a builing and draft gear and said bulkhead being adapted to serve as abutment for the buiiing gear, and a removable cover plate structurally connected to the side walls, extending in outboard direction beyond said bottom plate and constituting a main stress transmitting element of the center sill structure.

15. End underframe for vehicle bodies especially railway cars comprising a center sill portion having transversely spaced upstanding side walls interconnected by transversewebs, one of said webs extending from a point near the top at the outboard end of the center sill portion at a gentle slope in inboard direction to a point near the underside of the center sill portion so as to direct compression forces exerted on the center sill near its outboard end toward the underside of the sill and to interbrace the side walls of the sill, the inboard margin of said web merging into and being secured to a generally horizontal plate which extends inboard beyond said web and is secured to said side walls.

16. In a center sill for railway cars and the like, a pair of transversely spaced longitudinal side walls constituted mainly by rolled U-sections, part of the vertical web and one arm of each U- section being cut out along part of the length and near the lower margin of the sill and replaced by an angle section member of heavier gauge, one arm of which member is welded along its margins to the margins of the cut-out of the web whereas its other arm-has its ends welded to and arranged in continuation of the adjoining portions of the lower arm of said rolled sections.

17. Center sill for railway car and the like vehicle bodies, having two transversely spaced lonsitudinally extending upright side walls interconnected by a transverse generally longitudinally extending web and by a transverse structure generallyv triangular in side elevation arranged outboard of the end of said web, said structure having its one side arranged substantially vertically with its middle at about the height of the outboard end of said web and being adapted as abutment for compression transmitting means and its other two sides converging inboard upon and secured to the end of said web.

18. Center sill for railway car and the like vehicle bodies, having two transversely spaced longtudinally extending upright side walls interconnected by a transverse generally longitudinally extending web and by a transverse structure generally angle shaped in side elevation arranged outboard o f the end of said web, said structure having its apex arranged at the height of and secured to the outboard end of said web and its two arms diverging outboard vupwardly and downwardly respectively, the outboard ends of said arms merging into generally horizontal longitudinally extending vertically spaced webs secured to and reinforcing said walls outboard of said structure.

19. In an end center sill for underframes of railway cars and similar vehicles, longitudinally extending and transversely spaced side walls intei-connected by a web sloping at least over part of its length in downward and inboard direction, a transverse bulkhead arranged beneath said web and secured to the same as Well as to said side walls, a bottom plate interconnecting the lower margins of the side walls in the region of and secured to said bulkhead, said side walls, web and bulkhead constituting together a pocket for a buing and draft gear and said bulkhead being adapted to serve as abutment for the buiiing gear, and a removable cover plate structurally connected to the side walls, extending in outboard direction beyond said bottom plate and constituting a main stress transmitting element of the center sill structure.

20. In an end center sill for underframes of railway cars and similar vehicles, longitudinally extending and transversely spaced side walls having their upper portions over at least a part of the length of the sill interconnected by a transverse web, a transverse bulkhead arranged beneath said web and secured to the same as well :.s to said side walls, a bottom plate interconnecting the lower margins of the side walls in the region of and secured to said bulkhead, said side REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 832,623 Pronty Oct. 9, 1906 861,313 Ostrander July 30, 1907 1,002,469 Summa Sept. 5, 1911 1,274,113 Wareld July 30, 1918 2,366,709 Dean Jan. 9, 1945