US26290A

US26290A - Propeller and paddle-wheel shaft

Info

Publication number: US26290A
Authority: US
Publication date: 1859-11-29
Anticipated expiration: 1876-11-29

Description

UNITED STATES PATENT OEE-ICE.

WILLIAM PETERS, OF BALTIMORE, MARYLAND.`

PROPELLER AND PAnDLE-WHEEL SHAFT.

Specification of Letters Patent No. 26,290, dated November 29, 1859.

To all whom 'it may concern:

Be it known that I, WILLIAM PETERS, of the city of Baltimore, in the State of Maryland, have invented a new and useful Improvement in Constructing Propeller and Paddle-lVheel Shafts; and I do hereby de-` clare that the following is a full and exact description thereof, reference beinghad to the accompanying drawings and to the letters and marks thereon.

The object of my invention is to construct a shaft for propellers and paddle-wheels which in case of sudden and violent strain, such as the shafts of ocean Steamers are subject to, will not be liable to cross or direct fracture and the entire separation of the fractured ends from 4each other, as It is well known `has often occurred when the shaft was made entirely either of wrought or cast metal. The evil sought to be overcome by my invention has been essayed in constructing compound shafts in which wrought iron rods or bars, placed longitudinally or otherwise, have been surrounded with cast iron. The efforts in this direction have not, however, been successful, and in violent strains such shafts have usually yielded in the line of direct fracture.

The principle upon which my shaft is constructed, as will readily be seen, is opposed to direct fracture, as the strain is necessarily distributed and removed from the line of its force, z'. e., from the line of direct fracture at right angles to the line of the shaft.

The drawings forming part of this specification show how I carry out my invention.

Of these drawings Figure l is a longitudinal section of a complete shaft with the bearing ends for the molds attached; Fig. 2, being a side view of theshaft showing the broadest surface of one of the threads formed upon the periphery of the inner part or portion of the shaft, and Fig. 3 showing the interrupted 0r .broken condition of the'same thread by forming of other threads.

This improved shaft is made up of wrought and cast metal, or it may be made entirely of cast metal. When made of cast metal I prefer lthat the meta-l of the exterior Aportion of the shaft shall be different from that forming the interior part. Having se- Y lected the material of which to make the letter (a), I have cut upon it, as shown by i the drawings, `four screw threads, which threads in case this interior part be of cast I metal can be formed when this part iscast by the process knownxas casting Screw threads?"` In turning `these threads `upon the wrought metal interior the first thread is made continuous from right to left the r entire length of the interior shaft, the sec-` ond thread likewise continuous fromleft to right, while the third andfourth are made in the character of right `and left handedll threads, each commencing at` one end ofthe shaft and termin-ating atl the center or half the length. The twofirst named threads, by` the drawings are shown `by the yellow coloring and the two latter bythe blue coloring.

`Having this portion of the shaft thus `prepared it is placed in the mold for thef cast-` ing around it the exterior portion. The ends of the shaft beyond` the yellow colored part of Eig. 1, and beyond 'uit` dotted unes or Figs. 2 and 3, represent the bearing part y which in the mold and` which `are removed `80 on finishing the shaft. It is understood that the molds will have beenprepared for the placing in them this interior part of the shaft. The exterior part is then formed by running in the molten metal upon and around the interior portion.` This exterior or the interior may befwroughtiron and the exterior cast iron. A Shaft construct-` ed in this manner will 1 in case of, strain have a uniform distributionof `the force in the direction of itslgthand willsuccessfully resist fractures in a line at right angles to its length. y

It is` evident that this construction is susceptible of being used in making other articles than propellers and `wheel shafts, as it may be extended to mill spindles, pieces of ordnance, and other shafts where 1t is de` sirable to provide aga-inst` force exerted in opposing directions to the line of the Shaftgj Having thus set out my invention what I claim as new and desire to secure by Let--` ters Patent is- A propeller or paddle-wheel shaft constructed as herein set forth.

Witnesses:

JOHN S. HOLLINGSBEAD,

W. S.` CIIARY.

wM. PETERS. i