US1222625A - Sprocket-wheel. - Google Patents

Description

W. HAY.

SPROCKET WHEEL,

APPLICATION r1150 AUG-H- 191a.

jl fi fiu Patented Apr. 17, 1917.

fee

WALTER HAY, 0F SEVILLE, OHIO.

SPBQCKET-WHEEL.

Application filed August 11, 1913.

To all whom it may concern Be it known that I, WALTER HAY, a citizen of the United States, residing at Seville, in the county of Medina and State of Ohio, have invented new and useful Tmprovements in Sprocket-Wheels, of which the following is a specification.

This invention relates to sprocket-wheels in which the teeth are formed independently of the body portion.

The principal objects are to provide a sprocket-wheel constructed largely of sheet metal and in which the accuracy of milled teeth is combined with the cheapness of punch-press products; in which each separate tooth is formed with a section of the wheel rim, thus enabling the teeth and the rim to be heat treated and then assembled absolutely true to pitch; in which the teeth are firmly, yet removably secured to the body in such manner as to prevent them from becoming loose, regardless of the length or severity of service; and in which the hub and the method of securing same to the body portion or web conform to the other parts of the wheel in simplicity, cheapness and dependability.

I am aware of the fact that toothed wheels have been devised. heretofore in which the teeth were formed from a continuous strip of sheet metal and then secured to the rim or body portion; also that sheet metal teeth have been formed separately and then secured into the body portion. However, with the former construction, hardening of the teeth in strips would destroy the accuracy of the pitch, and a broken tooth could hardly be replaced without renewing the entire strip of teeth. With the latter construction, in all cases known to me, each tooth requires two separate fastening means, and where the body portion is solid and sufliciently thick to accommodate wide teeth or wide chains, the cost of material and machine work would show no economy over a solid wheel with milled teeth; were the body portion more cheaply constructed with two sheet metal disks, then objectionable openings would appear between the teeth, and the rim bearing-surfaces for achain would be.

inadequate; and were it desired to harden the rim, the accuracy of the pitch would be destroyed during heat treatment.

It is believed that the foregoing brief thesis on other wheels having sheet metal teeth, when considered in connection with Specification of Letters Patent.

Patented Apr. 1?, 1915?. Serial No. 784,160.

the followin detailed description, will enable a clearer understanding of the features of improvement comprised in my invention.

quently presenting the appearance of a sheave. Equally spaced around the outer edge of the body disks are oppositely dis posed circular openings 12 (see also Fig. 3), with slots 12 extending therefrom and through the rim. The tooth 13 (see also F td and the rim section 13 are constructed of one piece of sheet steel, the ends of which project inwardly through the slots 12. and have a semi-circular form 13 and 18 to correspond with the openings 12. In assembling, two or more teeth with their integral rim sections are entered into the body portion from the side, the rim sections fitting closely the periphery of the body-disks, and the semi-circular end of a rim section and the semi-circular end of an adjoining tooth are brought together in each of the openings 12, thus forming practically a series of tubes in halves, into each of which tubes thus made is forced around pin 14 which causes expansion of the tubes and thereby the teeth and rim sections to be firmly and dependably secured to the bodydisks.

From a study of Fig. 1 it is obvious that the openings 12 and slots 12 can be made true to pitch and at low cost in a punchpress by aid of an indexing device, and if the wheels were to be made in large quantities, all the openings and slots could more cheaply be punched in one operation; also that there being no wear on the rims of the body-disks, hardening of same is unnecessary and consequently the diameter of same and the pitch of the slots always remains true; also that the width of the slots, which are preferably made radial, is only twice the thickness of the sheet steel used for the teethrim sections, hence the latter are rigidly secured against lost motion and mutually braced to withstand the pull of a chain. Each tooth with its respective rim section being a unit, hardening of same causes but slight change in its form; however, all Shrinkage or distortion resulting from heat treatment is rectified in assembling, the radial slots in the body-disks bringing each tooth true to pitch. By removing two pins any broken or injured tooth-rim section may easily be replaced; and similarly, when considerably worn, all the teeth can be replaced with new, the body, disks, due to the protection afforded by the rim sections, retaining their original diameter and so helping to maintain the original pitch-diameter of the chain when the teeth-rim sections are renewed, or possibly reversed. Further, it will be observed that, for the purpose of securing the teeth-rim sections to the bodydisks, there are only as many fastening means as there are teeth, which method promotes economy in several ways.

In order to extend, primarily, cheapness of construction, and, along therewith, rigidity and exactness to every detail of my new sprocket-wheel, I have adopted the hub construction shown in section in Fig. 2. The hub 15 is preferably made of steel, somewhat higher in carbon than the body-disks, and around the outside circumferentially is turned an oval-shaped raised portion 15 which is then knurled, the resulting teeth running lengthwise of the hub. The bodydisks are assembled on the hub, one on each s1de of the ralsed portlon, and the whole placed in a powerful press which, with the aid of a guide stud to square the hub and the proper gaging arrangement, forces the two bodydisks together and over the knurled raised portion (the teeth cutting into the softer metal of the body-disks). The body-disks are then riveted together, thus rigidly securing the hub thereto, the teeth made by knurling-preventing movement of the body-disks circumferentially, and the oval shape of the raised Copies of this patent portion preventing movement of same laterally, both relatively to the hub.

What I claim as my invention is 1. In a sprocket wheel, the combination of a body comprising disks, each of said disks having a hub opening, having a curved portion to provide an annular channel when the disks are in engagement with each other, a plurality of independent tooth sections, each tooth section having ends extending toward the hub opening, each end having a curved portion whereby when the adjacent ends of the tooth sections are brought together, the curved portions form circular portions, a pin extending through each of the annular channel between the disks and through circular portions for holding the teeth between the disks, and means for securing the disks together adjacent the hub openings.

2. In a sprocket wheel, the combination of a body, a plurality of independent tooth sections formed with chain-supporting extensions, each tooth section having its ends extended into the body, each end having a curved portion whereby when the adjacent ends of the tooth sections are brought together, the curved portions form circular or tubular portions, and. a pin extending through each of the circular portions for securing the tooth sections to the body.

3. In a sprocket wheel, the combination of a body, a plurality of independent tooth sections, each tooth section having its ends extended into the body, each end having a bent portion whereby when the adjacent ends of the tooth sections are brought together, the bent portions form tubular portions, and means cooperating with the tubular portions for securing the tooth sections to the body.

WALTER HAY.

Witnesses i H. E. KRAMER, W. G. BRUMBAUGI-I.

may be obtained. for five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

and each disk

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