An Improved Method of Adjusting the Driving Chains of Velocipedes.
Year: 1894

page_text: PROVISIONAL SPECIFICATION.
j
An Improved Method of Adjusting the Driving Chains of
Velocipedes.
!
THOMAS TEBBUTT HARRISON Abbots Lodge Lower College Green Bristol
Teaman do hereby declare the nature of this invention to be as follows:-
To carry out my invention, I cut away the rearward half (or thereabouts) of the.
adjusting pin together with its nut, and in their stead, I pass through the aperture
in the centre of the cap, a tubular pin or case, whose inner surface is threaded to
correspond with that portion of the solid adjusting pin which remains attached to
the ring encircling the axle of the driving wheel.
The tubular portion of the adjusting pin is provided with a shoulder, which
presses against the inner or forward face of the cap, and also with a fixed head,..
which presses against the outer or rearward face of the said cap.
When by means of its head, the tubular portion of the adjusting pin is turned in
its socket in the cap, the solid portion is drawn into and contained within the
tubular portion, and the desired stretch of the driving chain is thus attained.
The cap and the ends of the tynes of the fork are suitably provided, with nuts or
screws, so that the cap may be removed when necessary to take out the driving
wheel; or the cap may be cut into two portions, and furnished with screws as
above for the same reason.
A's a modification of the invention :
The shoulder on the tubular portion of the adjusting pin, and also the screws or
nuts which fix the cap to the tynes of the fork, may be dispensed with.
.
The invention may be carried out equally well as regards the above mentioned
modification, by reversing the positions of the solid and the tubular portions of the
adjusting pin. The solid portion then passes thro' the cap and is provided with a
fixed head, while the hollow portion is attached to the ring encircling the wheel
axle.
Dated this 18th day of December 1894.
COMPLETE SPECIFICATION.
An Improved Method of Adjusting the Driving Chains of
Velocipedes..
.3
I, THOMAS TEBBUTT HARRISON of Abbots' Lodge, Lower College Green,
Bristol, in the County of Gloucester, Tea Dealer's Mauager, 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 :→
To carry out my invention I cut away the rearward half (or thereabouts) of the
adjusting pin together with its nut and in their stead I pass through the aperture
in the centre of the cap a tubular pin or case the inner surface of which is threaded
to correspond with that portion of the adjusting pin which remains attached to the
ring encircling the axle of the driving wheel..
-

page_text: The tubular portion is provided with a shoulder which presses against the inner
or forward face of the cap and also with a fixed head which presses against the
outer or rearward face of the said cap. When, by means of its head the tubular
pin is turned in its socket in the cap, the solid portion is drawn into and contained
within the tubular portion and. the desired stretch of the driving chain is thus
obtained. The cap and ends of the tines of the fork are suitably provided with
screws or nuts in order that the said cap may be easily removed when necessary to
take out the driving wheel; or the cap may be divided in two portions and suitably
provided with screws as above. As a modification of the invention the shoulder
on the tubular portion of the adjusting pin and the screws fixing the cap to the
ends of the tines of the fork may be dispensed with.
The invention may be carried out equally well as regards the above mentioned
modification by reversing the positions of the solid and. tubular portions of the
adjusting pin the solid portion then passing through the cap and is provided with
a fixed head while the hollow portion is attached to the ring encircling the wheel
axle.
It will be seen that the object of my invention is to abolish that portion of the
adjusting pin which in the ordinary adjusting device protrudes beyond the nut.
By so doing I remove a source of danger to the cyclist, and render the adjustment
more compact, and neat in appearance.
In order that my invention may be more fully understood I append a sheet of
drawings in which:
Fig. 1 is an elevation of the back fork of a bicycle showing my improved
adjusting device in position.
Fig. 2 is a sectional elevation of same.
Fig. 3 is a view of the face of the cap.
Fig. 4 is a modified form of adjuster.
A designates one of the members of the frame of a rear driving safety bicycle,
and B the fork, which in general forms the junction piece for this and another
member not shewn. There are in the case of a rear driving bicycle of the ordinary
type, two of these. forks, one on. each, side of the wheel, and both are formed
integrally with. or rigidly attached to such members of the one frame. The fork
is formed with the usual slot b in which slides one end of the central pin round
which the wheel rotates. My improved adjusting device is constructed and
applied to this ordinary type of fork as follows:-A cap C is used which is
hollowed out at c¹ so as to fit over and enclose the ends of the fork B, thus
retaining the cap in the position shewn. Through this cap C in a line with the
slot is bored a hole c, in which fits loosely so as to be revoluble, the sleeve D,
having a flange d and a polygonal head d. The flange has in general a milled
edge, which enables it to be turned by the fingers, or a spanner can be applied to
the head and used for the same purpose. The sleeve is bored through nearly
its whole length, and screw threaded internally so as to engage with the threads of
a pin e this forming part of a ring E which encircles one end of the central pin
upon which the wheel rotates.
If now the wheel is supposed to be in position with one end of its central pin
passing through the fork slot, b and the ring E, and the other end passing through
a similar fork, slot, and ring upon the other side of the wheel, the latter may be
drawn towards the caps C, or allowed to recede from them simply by turning the
head d and internally screwed sleeve D. The screwed pin e is not revoluble, so
that the turning of the sleeve in one direction draws the ring E and spindle towards
the caps C; and the turning in the other direction allows it to move away from
the caps. By this means the spindle with the wheel, hub, and chain wheel is
caused to slide along the slots 6 either away from or towards the driving (chain)
wheel, and thus the chain may be adjusted readily, conveniently, and exactly.
The adjusting device shewn in Fig. 4 operates in precisely the same manner, but
the arrangement of parts is the converse of the preceding. In this case C is the
cap, in which the male screw G turns, while the sleeve H (which is formed.

page_text: integrally with the ring E) is screwed internally to fit the male screw G. By
turning this screw either by its milled flange g, or head g', the sleeve H and ring E.
with the spindle and wheels are caused to slide backwards and forwards as before
described with reference to Figs. 1, 2, and 3.
My invention is equally applicable and in the same manner to tricycles and
other velocipedes.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. In an adjusting device for the chains of bicycles and other velocipedes, the
combination of a cap C, an internally screwed sleeve D having a head d', and a.
male screw formed integrally with a ring E, substantially as shewn and
described.
2. In an adjusting device for the chains of bicycles and other velocipedes, the
combination of a cap C a male screw G, having a head g¹, and an internally
screwed sleeve H, the latter being formed integrally with a ring E, substantially
as shewn and described.
3. Io an adjusting device for the chains of bicycles, and other velocipodes, the
combination of parts as hereinbefore described and illustrated in the accompanying
drawings.
Dated this 19th day of Sentember 1895
WILLIAM J. MUNDEN,
106 Priory Park Road, Kilburn, London, N.W.,
Agent for the Applicant.