US592871A - Velocipede - Google Patents

Description

no Model.) 2 Sheets-Sheet 2.

E. G. LATTA.

VELOGIPEDE.

No. 592,871. Patented Nov. 2,1897.

UNITED STATES PATENT @FFIQE.

EMMIT G. LATTA, OF FRIENDSHIP, NEWV YORK.

VELOCIPEDE.

SPECIFICATION forming part of Letters Patent No. 592,871, dated November 2, 1897.

Application filed April 9,1896. Serial No. 586,765. (No model.)

To aZZ whom it may concern:

Be it known that I, EMMIT G. LATTA, acitizen of the United States, residing atFriendship, in the county of Allegany and State of New York, have invented new and useful Improvements in Velocipedes, of which the following is a specification.

My invention relates to a crank-shaft and supporting-bracket for velocipedes.

It has the objects to produce at small cost a bracket which shall combine great strength and lightness, to secure the bracket to the frame of the machine in aneat and reliable manner, and to connect the crank-shaft, cranks, and sprocket-wheel by simple, cheap, and positive means without the employment of projecting keys and in such manner as to permit the ready detachment of the parts without the use of special tools.

In the accompanying drawings, consisting of two sheets, Figure l isa sectional side elevation of the bracket and adjacent parts. Fig. 2 is a sectional plan view thereof. Fig. 3 is a side elevation of the bracket and frame members with the shaft and bearings omitted. Fig. 4c is a detached rear view of the bracket. Fig. 5 is a longitudinal section of the right-v hand end of the shaft, the sprocket-wheel hub, and the crank. Fig. 6 is a detached face view of the inner portion of the righthand crank. Fig. 7 is a sectional elevation of a modified construction of the crank-shaft and sprocket-wheel.

Like letters of reference refer to like parts in the several figures. v

The bracket is cylindrical in form and consists of two cylindrical parts or tubes A A, preferably constructed ofsheet-steel and arranged concentrically, or one within the other. The outer part A is formed with projecting lugs or thimbles a for receiving the inner portions of the adjacentmembers or tubes B, B, and B of the frame. These thimbles are shorter than they are usually made and are preferably formed by first making openings in the bracket slightly smaller than the frametubes, then turning the edges of the openings outwardly to form the projecting rims or thimbles a, and then reaming them out to a thin or feather edge to fit the tubes. This method is much less expensive than that of drawing the thimbles out of the metal of the extend to the bottom of their seats.

bracket to the usual length, as has heretofore been the custom.

' The inner part A of the bracket is pro vided in its outer surface with comparatively shallow depressions c,which coincide with and are made of the same size as the thimbles of the outer part A and which form seats or sockets for the inner ends of the frametubes, as most clearly shown in Figs. 1 and 2. In these seats the tubes are secured by brazing, forming avery reliable connection. The registering thimble and depression of each pair thus form together a tube-seat arranged partly inside and partly outside of the bracket,

providing a brazing-surface for the tube about equal to one-half of its diameter, in addition to the side bearing of the ends of the tube. The bottoms of the depressions c are curved concentrically with the bracket, and the contiguous ends of the frame-tubes are correspondingly curved. The inner ends of the frame-tubes are covered or closed by the bottoms of the depressions 0, thus further strengthening the connection and at the same time preventing the spelter used in brazing from running into the bracket.

The ends of the front and upright tubes B B meet Within the bracket and are mitered or flattened at their contiguous portions, as shown in Figs. 1 and 3, to permit the same to In brazing these flat sides are united, adding materially to the strength of the connection. The seats of the tubes B and B communicate or open into each other, as there is not sufficient room for a division-Wall between the same.

The depressions in the inner part A for the reception of the rear-fork tubes B are not of equal depth across their entire width or diameter, but diminish in depth outwardly or toward the ends of the bracket, so as to leave sufficient room in the ends of the bracket for the usual bearing-cups d d, as shown in Fig. 2, the front ends of the fork-tubes being madeto conform to the bottom of said seats.-

The two cylinders forming the bracket are of uniform length, and each has a butt or flush joint extending lengthwise thereof, the joints of the two parts being arranged out of register, as shown in Fig. 3, to prevent opening of the joints after the same are brazed. As soon as the frame-tubes are inserted into the seats of the bracket the inner part of the latter is locked within the outer part, and by the brazingof the tubes in their seats the two parts of the bracket are firmly united and their meeting edges are joined all at one brazing operation, producing a bracket practically as strong and solid as a forged bracket and at much less cost.

The thimbles a of the bracket are preferably so short that by reducing them to a thin edge the frame presents the appearance of having flush joints.

The short liners or reinforcements commonly used to strengthen the tubes attheir junction with the bracket are not shown in the drawings, but they may obviously be used or not, as desired, and arranged either inside or outside of the tubes.

As a modification of the bracket the thimbles of the outer part might be omitted and said part be provided simply with holes registering with the seats of the inner part, in which case the joints would be flush. This construction would be much less expensive than the usual flush joints formed by extending lugs from the bracket into the frametubes.

If desired, the bottoms of the seats or depressions c in the inner part of the bracket may be perforated, but this would not produce so strong a'construction as the closed seats. depth than that shown, and they may be made to fit tubes of different eross'sections without extra expense other than that of the dies.

If preferred, one orboth parts of the bracket may be made of seamless tubing, but such a construction would be less desirable.

E is the crank-shaft,arranged in the bracket and having the usual bearing-cones e e, and f are the rows of balls interposed between said cones and the bearing-cups d d. The latter may engage with the ends of the bracket by screw-threads, as shown, and the right hand cup is fixed and has ashoulder d bearing against the end of the bracket, while the left-hand cup is adjustable and carries a check or lock nut g, which bears against the adjacent end of the bracket.

A crank-shaft of mild steel, having cones of high-carbon steel shrunk thereon and subsequently turned to the proper form, tempered, and ground, is regarded as the best construction for the shaft-bearings. In order to adapt such a shaft to my improved bracket in a manner to permit the left crank to be placed closely to the end of the bracket and avoid the use of projecting keys and so as to permit the easy detachment of the shaft without tools other than the usual wrench, a detachable crank H, of the type commonly known as the fixed variety, is employed at the left-hand end of the shaft. This is a crank fitted closely on the end of the shaft and secured thereto by a key or feather h, arranged parallel with the shaft and driven into a feather way or seat formed partly in the The seats may be of greater or less crank-hub and partly in the shaft. In order to detach this crank, it is necessary to first remove the shaft from the bracket. Otherwise there is danger of injuring the bearings. To readily detach the crank and at the same time permit the sprocket-wheel I to be changed, the right-hand crank J is constructed as shown in Figs. 2 and 5. This crank is preferably flat on its outer face and fluted on its inner face and has perforated radial arms or lugs j at its inner end and a flat-sided openingj in the center of its hub which fits over the tapering flat-sided end of the shaft. The hub or collar 1', forming the central portion of the sprocket-wheel, is provided with an internal screw-thread i, which engages with an external thread 7;, formed on the crank-shaft immediately on the inner side of its flatsided end. The arms of the sprocket-wheel are formed with holes adapted to register with those of the crank arms or lugs j, and through these coinciding holes pass fastening screws or bolts 1, whereby the sprocketwheel is compelled to turn with the righthand crank. The hub of the sprocket-wheel has the requisite length or bearing-surface to prevent stripping of its threads. To afford the necessary length, the inner face of the adj acent crank-hub is slightly rccessed,as shown at min Figs. 2 and G, and the hub is extended into the right-hand bearing-cup.

In connecting the parts of the crank-shaft and applying the latter to the bracket the left-hand bearing-cup, with the lock-nut g and the complementary balls, is first placed on the left-hand end of the crank, and the left crank is then driven upon the shaft and firmly keyed in place. The shaft is then placed in the bracket and the left-hand cup screwed into the adjacent end of the bracket. Then the right-hand cup, with its balls, is passed over the end of the shaft and screwed into the end of the bracket to its limit. The sprocket-wheel is next screwed upon the shaft, the right-hand crank is then applied to the crank-shaft, and the fastening-bolts Z are finally put in place and tightened, whereby the right-hand crank is firmly drawn into position on the end of the shaft. This forms a very rigid connection, which is equally secure against the pressure applied in driving the machine forward and against the force exerted in back-pedaling. This construction afiords the important advantage that in detaching the parts, after removing the bolts Z, the act of unscrewing the sprocket-wheel loosens or forces the right-hand crank from its seat on the shaft. It has the further IIO advantage of forming a perfect adjustment for taking up wear or looseness between said crank and the shaft by simply tightening the bolts, or, if necessary, by loosening the bolts, screwing the sprocket-wheel farther inward on the shaft, and again tightening the bolts any wear may be taken up. This connection of the sprocket-wheel hub or collar and the crank is preferably made by several bolts, so

that the parts are secured together on difierent sides of the shaft. In practice it has been found that from three to five bolts are desirable. In order to secure a fine adjustment, so that a very slight looseness of the crank on its seat may be taken up and the crank arms or lugs j and the web of the sprocket-wheel kept in close contact, it is desirable to arrange the several bolts at equal intervals around the shaft and at exactly the same distance from the axis of the shaft, so that the collar or sprocket-Wheel maybe given a complete turn or screwed only from one bolt-hole to another, as may be necessary to obtain a close fit of the parts. sirable that none of the bolts should be passed through the crank-arm itself, because when the web of the sprocket-wheel is connected with the crank-arm and the latter becomes bent the sprocket-wheel is liable to be bent or thrown out of alinement.

The modification'illustrat'ed in Fig. '7 shows a construction which next to a crank-shaft having bearing-cones turned on its body is the most desirable construction. This consists in forming the cones on a sleeve N, which is connected to the shaft. The left-hand crank is formed in one piece with the shaft, While the opposite crank is applied to the shaft and provided With radial arms, as in the first-described construction. The sprocket-wheel is in this case made of sheet metal and formed with a central opening which receives the shaft. A separate internally-screw-threaded collar or hub I, having radial arms 1 engages with the right-hand screw-thread of the shaft, the fastening-bolts in this case passing through holes formed in the web of the sprocket-wheel and in the arms of said collar, whereby the right-hand crank is drawn into place, as hereinbefore described, and the sprocket wheel is at the same time held against turning on the shaft. In this conrection.

It is also de modification after detaching the removable crank and the collar 1 the sleeve N may be held against turning by a suitable wrench and the shaft unscrewed from the sleeve and removed, leaving the sleeve and the bearings undisturbed.

The right-hand end of the crank-shaft and the opening of the adjacent crank-hub may.

be of any other suitable form that will compel the crank to turn with the shaft.

I claim as my invention- 1. A crank-shaft bracket comprising an outer tube or cylinder having openings for the passage of the frame members and an inner contiguous tube or cylinder forming with the outer tube a double-walled bracket, and provided opposite the openings of the outer tube with depressed seats or sockets which receive the ends of the frame members, substantially as set forth.

2. A crank-shaft bracket comprising an outer tubular part, having an outwardly-projecting socket or thimble, and an inner tubular part having a depressed or inwardlyextending seat or socket registering with the socket or thimble of the outer part, said coinciding thimble and socket being adapted to receive a frame member, substantially as set forth.

3. The combination with a crank-shaft havin g an angular end and a screw-threaded portion adjacent thereto, of an internally-screwthreaded sprocketwheel hub or collar engaging with said screw-threaded portion, a crank having its boss interlocked with the angular end of the shaft and constructed to surround the same and capable of removal from the shaft independently of the sprocket-wheel,

and bolts connecting the crank with said sprocket-wheel hub or collar, substantially as set forth.

Witness my hand this 31st day of March, 1896.

EMMIT G. LATTA. Witnesses:

GEO. W. FRIES, H. L. BLossoM.

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