US1995849A - Car roof - Google Patents

Description

March 26, 1935-? G. G. GlLPlN 1,995,849

` CAR ROOF I Filed April 18, 1951 Z @All/rom Ww f// @Troie/vers.

Patented Mar.- 26, 1935 PATENT oFFlcE ROOF Garth G. Gilpin, Riverside, Ill., assigner to P. H.

Murphy Company, New Kensin corporation of Pennsylvania Application April 18,

Claims.Y

This invention relates to car roofs of the socalled neutral axis type wherein the metal roof sheets are shaped and secured together to form a roof consisting of alternating ribs and chan- 5 nels, and the roof as a whole functions mechanically as a beam supported on the side plates of the car. The principal object of the present invention is to provide a roof of this type with reinforcing members whose structure and position serve toincrease the strength and load carrying. capacity of the roof without increasing the overall depth thereof. Other objects areV simplicity and cheapness of construction, ease of assembly and fewness of parts. The invention consists in the parts and arrangements and combinations of parts hereinafter described and claimed.

In the accompanying drawing, whereinrlike symbols refer to like parts wherever they occur,

Fig. l is a plan View of a portion of a car roof embodying my invention,

Fig. 2 is a vertical cross-section through onehalf ofthe roof on the line 2 2 in Fig. 1,

Fig. 3 is a similar cross-section on the line 3--3 in Fig. l,

Fig. 44 is a `vertical longitudinal section on the line 4-4 in Fig. 1; and

Fig. 5 is an enlarged vertical cross-section on the line 5-4-5 in Fig. 1.

In the present construction, the roof sheets 1 are arched and span the space from side plate 2 to side plate 2, their ends being turned down and riveted or otherwise rigidly secured to such side plates. Conformably to the so-called neutral axis type of roof, the roof sheets l'of the present invention are shaped and secured together to form a series of hollow flat-topped ribs A at one level alternating with a series of flatbottomed channels B at a lower level, which extend transversely of the car and function after the manner of a beam supported on such side plates. The ribs and said channels are preferably of substantially equal cross-sectional area with the ribs merging at or near the ends of the roof sheets into the plane of the bottom of the channels.

According to the present invention, the longitudinal middle portion 3 of each roof sheet 1 is offset downwardly with respect to the side portions 4 thereof thus forming a channel B, 50 such middle portion and the side portions being integrally connected throughout their length by upstanding web members 5 that decrease in height from a maximum at the ridge to a minimum depth at the eaves where the roof sheet is turned down and riveted to the side plates. The

1931, 'serial No. 531,092 (o1. 10s-5.4)

roof `sheets are arranged side by side with the side portions 4 of adjacent sheets overlapping and rigidly secured together, preferably by rows Of rivets 6, the width of the side portions 4 Vand the amount-of the overlap being such that the width 5 of the `ribs Arformed by theside portions of adjacent sheets` will be substantially equal to the width of the channels B.

Located within each hollow roof rib A is a hollow reinforcing member 7,'preferably of channel-shapedcross-section, with lateral flanges 8 at the upper edges of its side walls. Each reinforcing member 7 extends from side plate to side plate midway between the sides of the rib 'within which itis located with one of its lateral top flanges 8-located vbeneath and rigidly secured to the overlapped margins of the side portions of adjacent sheetsby the row of securing rivets 6 therefor.` The other lateral top flange 8 of the hollow reinforcing member 7 is secured toY the portion of the roof sheet located thereabove by a second row of rivets 9. The hollow reinforcing members '7 are preferably secured at their ends to the side plates 2 and they cooperate with the overlapped side portions of the roof sheets located above them after the manner of hollow box girder carlines. It is noted that the reinforcing members are all located Vwithin the hollow ribs A of the roof and are mainly or wholly between the upper and lower levels thereof. If desired, the sheets and reinforcing members may be shaped to bring the neutral axis of the roof as a whole approximately midway between the upper and lower surfaces of the roof, thereby enabling the maximum strength of the metal to be utilized. As the stiffening effect of the sides of the panel and the sides of the hollow seam construction decreases with the distance therefrom, it is desirable to make the width of the seam construction approximately one-third the width of the rooi rib or panel, as illustrated in Figs. 4 and 5. By this arrangement, the entire width of the roof rib or panel participates in taking care of the compressive stress therein.

It is a great merit of the roof above described that all the metal in the roof participates in taking care of the load after the manner of action of a beam supported by the side plates, and that the compression strength of the roof is greatly augmented by the reinforcing members which increase the capacities of the upper middle portions of the ribs for taking care of the stresses which tend to buckle them. It is also noted that the middle portions of the channel-shaped sheets are located in the lower portion of the roof where 55 they are better adapted to take care of tensile stresses.

Members 10 are located below the roof sheets, and reinforcing members and extend longitudinally of the car at the ridge. These members are secured to the bottom of the reinforcing members 7 and serve as struts to stiften the roof and as a means for distributing the load between said reinforcing members. The members 10 also serve as lifting beams to which lifting tackle may be secured. Preferably such members are made in the form of an inverted channel with lateral base flanges adapted to be slidably engaged by the lifting tackle.

What I claim is:

l. A etal car roof having alternating nattopped ribs and fiat-bottomed` channels of substantially equal width formed therein extending cicsswise of the car, said roof consisting a! a plurality of roof sheets whose side margins are rigidly secured together, each o! which comprises side portions at substantially one level and a middle portion at a lower level, and channelshaped reinforcing members of a width about one-third that of the roof ribs, said reinforcing members being located inside the respective ribs midway thereof with their margins rigidly secured to the tops ofsaid ribs.

2. A metal car roof having alternating fiattcpped ribs and flat-bottomed channels o! substantially equal cross-sectional area formed therein and extending crosswise of the car, said roof consisting of a plurality of roof sheets whose side margins are overlapped and rigidly secured together, the side portions of each of said sheets being at one level and the middlel portion of each sheet being at a lower level, and channel-shaped reinforcing members located within said ribs substantially midway between the sides thereof and rigidly secured to the tops thereof along lines distant from the sides of the rib about one-third of the width of the rib.

3. A metal car roof having alternating flattopped ribs and flat-bottomed channels of substantially equal width formed therein extending crosswise of the car, said roof consisting of a plurality of roof sheets Whose side margins are rigidly secured together, each of which comprises side portions at substantially one level and a middle portion at a lower level, and channel-shaped reinforcing members of a width about one-third that of the roof ribs, said reinforcing members being located inside the respective ribs and midway thereof with their margins rigidly secured to the tops of said ribs, and members located beneath said sheets and connected to said reinforcing members and adapted to support the portions of the sheets located at the lower level and to constitute load-lifting beams.

4. A metal car roof having alternating attopped ribs and fiat-bottomed channels of substantially equal width formed therein extending crosswise of the car, said roof consisting of a plurality of roof sheets whose side margins are rigidly secured together, each of which comprises side portions at substantially one level and a middle portion at a lower level, and channel-shaped reinforcing members of awidth about one-third that of the roof ribs, said reinforcing members being located inside the respective ribs and midwayV thereof with their margins rigidly secured to the tops of said ribs, and members secured to said reinforcing members and extending crosswise thereof beneath and in contact with the lower portions of the roof sheets.

5. A metal car roof having alternating fiattopped ribs and flat-bottomed channels of substantially equal cross-sectional area formed therein and extending crosswise of the car, said roof consisting of a plurality of roof sheets whose side margins are overlapped and rigidly secured together, the side portions of each of said sheets being at one level and the middle portion of each sheet being at a lower level, and channelshaped reinforcing members located within said ribs substantially midway between the sides thereof and rigidly secured to the tops thereof along lines distant from the sides of the rib about onethird of the width of the rib, and members extending beneath said ribs, channels and reinforcing members and rigidly secured to the latter in contact with the undersides of said channels.

GARTH G. GILPIN.

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