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Publication numberUS244720 A
Publication typeGrant
Publication dateJul 19, 1881
Filing dateOct 18, 1880
Publication numberUS 244720 A, US 244720A, US-A-244720, US244720 A, US244720A
InventorsFredrick Hildebrandt
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fredrick hildebrandt
US 244720 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)




SPECIFICATION forming part of Letters Patent No. 244,720, dated July 19, 1881.

Application filed October 18,1880. (Nomodel.) l

the four-piece'stove-elbows, by which a neater,l

more durable, and stronger elbow is obtained.

The fourpiece elbows heretofore manufactured were made of two different gradesthe first grade having all the con nectingrivets of the four pieces or sections on the inside, so as to be out ot' sight, while the second or cheaper grade has the rivets on the outside. They are manufactured by cutting two sets of blanks from two sheets of sheet metal and using onelialf of the blanks obtained thereby for one grade and the other halt' for the other grade of elbows. Each middle piece of these elbows was provided at one end with an outwardlybent flange or lipv and at the other end with an annular bead, w hile the end sections had respectively ahead and a lip at their inner edges, which connected with the lip of one of the middle sections and with the bead of the other ln putting the sections to middle section. gether there is always considerable delay in springing the tongues or lips of one section into the connecting-beads of the adjoining section. Another objection was that in closing the beads over the lips by the bead-closin g machine a bad and faulty joint was obtained, which rendered the article unsightly and objectionable.

The object of this invention is to furnish a four or more piece elbow, which is quickly put together and uniformly connected without any tlaw or defect; and the invention consists of providing one middle section of the elbow7 with lips or tongues at both ends, and the second middle section with annular beads at both ends, and making the end sections, as before, with lip and bead respectively.

It consists, secondly, of making the blanks of the outerand middle sections,provided with annular beads at their ends, of slightly greater width than the outer and middle sections having end lips, thelatter sections being riveted closer to decrease slightly their diameter, so that an easier insertion of the pieces or sec- Similar letters of reference indicate corre-V spondin g parts.

In manufactu rin g in y elbows I prefer to make them also in two grades by cutting the blanks,

as heretofore, from two pieces Vof sheet metal, and using one-halt of the blanks so obtained for the first grade, in which the rivets are placed at the inside of the elbow, while the remaining blanks are used for the second grade,

.in which the rivets are arranged at the outside of the elbow. The middle sections of the first grade are preferably slightly bulged at their outer circumference, by which the elbow receives a more rounded and better appearance. The blanks of the first grade are marked in Roman figures I to IV, and the blanks of the second grade in Arabic figures 1 to 4 in Figs. 1- and 2 of the drawings. In making up the blanks care has to be taken that the blanks I and II of the first sheet are made of slightly greater width than' the blanks III and IV of the second sheet, the blankrI being then bead- 'ed at the inner edge, while blank IIis beaded at both ends. The remaining blanks III and IV are bent up with lips or tongues, and are riveted at their edges in such a manner that their diameter is slightly less than the diameter of the sections I and II.

By making one-half the blank-s of slightly greater width than the other halt' and reducing the' diameter of the latter, as described, the sections or pieces are joined without diflculty by simply throwing one into the other, so that no time is lost in springing one section into' the adjoining sections, as has been formerly the case.

By means of the slightly greater width of one-halt' of the blanks there is also secured a better overlapping of the beads over the lips when connecting the sections'in the bead-closing machine. In this manner considerable time and labor are savedin making the elbows.


Having thus described my invention', I claim as new and desire to secure by Letters Patent- A four or more piece stove-pipe elbow, in which the inner edge of one of the end sec- 5 tions und both edges of one of the middle seetions are provided with annular beads and made of slightly greater width and diameter than the'seeond middle and opposite end seetion, which are provided respectively at both 1o ends and at the inner end with outwardly-bent lips or tongues, all substantially as and for the purpose set forth.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two witnesses this 13th day of Octo- 15 ber, 1880.



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Cooperative ClassificationF16L27/0849