Improvements in Chain Adjusting Devices for Velocipedes.
Year: 1898

page_text: Date of Application, 22nd Nov., 1898-Accepted, 23rd Dec., 1898
[Communicated from abroad by CROSBY AND MAYER COMPANY, of 506, Genesee
Street, in the City of Buffalo, in the County of Erie, and State of New
York, United States of America.]
Improvements in Chain Adjusting Devices for Velocipedes.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:-
This invention relates to the adjusting devices employed on the rear fork ends
of velocipedes for adjusting the tension of the driving chain, and more especially
to adjusting devices of this kind comprising a shifting plate or washer connected
with the movable rear axle and an adjusting screw engaging with said plate.
The object of my invention is the provision of a simple and inexpensive chain
adjustment which is neat in appearance and which shifts the rear axle positively
in both directions.
Referring to the accompanying drawing:
Figure 1 is a side elevation of the rear fork end of a bicycle provided with
my improved adjusting device.
Figure 2 is a longitudinal section on line 2-2, Figure 1.
and
Figure 3 is a transverse section on line 3-3, Figure 1, looking forwardly.
Figure 4 is a plan view of the blank from which the shifting plate is formed,
Figure 5 is a detached perspective view of the shifting plate and a portion
of the adjusting screw.
Like letters of reference refer to like parts in the several figures.
A represents the members of the upper and lower rear forks of a bicycle
and B one of the usual flat sided fork ends connecting the fork members on
one side of the rear wheel. Each fork end is provided with the usual longi-
tudinal slot for the passage of the adjustable rear axle C. D is the hub of
the rear wheel mounted on said axle, E the usual small sprocket wheel
secured to the hub, and F the driving chain. All of these parts are of ordinary
and well known construction.
The rear axle is provided at each end and on the outer side of the fork end
with a shifting plate or washer G having at its rear end an eye g which encircles
the axle. H is an adjusting screw whereby the shifting plate G is moved on
the fork end for properly tensioning the chain. This screw engages in a screw
threaded opening formed in a lug or bearing which projects from the outer
side of the fork end and is arranged on the front side of the shifting plate.
The rear end of the screw is connected with the shifting plate in such manner
that the screw,
while capable of turning in the lug i and the plate is held
[Price Sd

page_text: against endwise movement on the plate, thus compelling the plate to move
toward and from the lug upon turning the adjusting screw in one or the other
direction. For this purpose, the shifting plate is provided at its front end with
a lip or ear projecting outwardly at right angles thereto and having a
slot which receives a cylindrical neck or reduced portion h formed near the
rear end of the adjusting screw. This neck while free to turn in the slot of
the ear is confined against endwise movement therein by the shoulder of
the screw at the front end of the neck and the head or shoulder h at the rear
end thereof, as shown in Figure 2, the slot of the ear being narrower than the
diameter of the screw. This slot is preferably closed at its outer end and
extends inwardly through the body or main portion of the shifting plate, as
shown in Figures 2 and 5.
The shifting plate is provided with a slot or opening which communicates
with the inner end of the slot of the ear g₁ and which is of sufficient width
to admit the head of the adjusting screw, so as to permit the neck of the
screw to enter the narrow slot of said ear. The shifting plate is preferably
stamped from a flat blank of sheet metal of the form shown in Figure 4.
punching the wide and narrow slots in the blank, its front portion is bent at
right angles to the body thereof to form the ear g¹.
After
By this construction, the eye of the shifting plate can be readily passed over
the rear axle and the slotted ear of the plate can be conveniently passed over
the head and neck of the adjusting screw. As the eyes of the shifting plates
or washers embrace the axle on its front and rear sides and the plates are held
against endwise movement on the adjusting screws, the axle is shifted positively
in both directions by the screws. After effecting the adjustment, the axle is
clamped by the usual end nuts j which bear against the outer side of the
washers or shifting plates. Upon loosening these end nuts sufficiently to permit
the slotted ears of the shifting plates to be disconnected from the adjusting
screws, the axle can be withdrawn rearwardly from the slotted fork ends, the
adjusting screws remaining attached to the fork ends and the shifting plates
being retained upon the axle by the end nuts thus preventing the parts of the
adjustment from becoming lost or mislaid.
This adjusting device is neat and sightly, it affords an ample range of adjust-
ment, and as it is arranged wholly on the outer side of the fork end, it does not
interfere with the wheel hub or its hearing cones.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated
to me by my foreign correspondents, I declare that what I claim is:-
1. The combination with the fork end having a slot and a lug provided with
a screw threaded opening, of the adjustable axle arranged in said slot, a washer
or shifting plate engaging with the axle and provided with a lip or ear having
an open slot, and an adjusting screw arranged in the screw threaded lug of the
fork end and having a neck or contracted portion arranged in the slot of said
ear, substantially as set forth.
2. The combination with the fork end and the adjustable axle guided therein,
of a washer or shifting plate engaging with the axle and provided at its front
end with a lip or ear having a slot which extends inwardly through the body
of the plate, said plate being provided with a slot or opening which is wider
than the slot of said ear and which communicates therewith, and an adjusting
screw arranged in a screw threaded lug on said fork end and having a neck or
contracted portion arranged in the slot of said ear, substantially as set forth.
3. The combination with the fork end and the adjustable axle guided therein,
of a washer or shifting plate provided at its rear end with an eye which encircles
the axle and at its front end with an ear having a slot which extends inwardly
through the body of the plate, said plate having a slot or opening which is wider
than the slot of said ear and which communicates therewith, and an adjusting

page_text: screw arranged in a screw threaded lug on the fork end and provided near its
rear end with a reduced portion forming a cylindrical neck which is arranged
in the slot of said ear and a head which is adapted to pass through the enlarged
slot or opening in the body of the plate, substantially as set forth.
Dated this 22nd day of November 1898.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.