Improvements in and relating to the Chain Adjustment of Cycles.
Year: 1899

page_text: Date of Application, 9th Sept., 1899
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Chain Adjustment of Cycles.
JOHN BOYD DUNLOP and JOHN BOYD DUNLOP, Junior, Ailesbury Road, Dublin,.
Gentlemen, do hereby declare the nature of this invention to be as follows;
The object of this invention is to produce a simple method of chain adjust-
ment for cycles which permits of the. driving wheel being easily removed,
without interfering with the adjustment of the chain.
The fork-end may be of the usual form.
ends are drilled and tapped. A metal block is provided which is adapted to
The wheel axle is short and its
slide in the slot of the fork-end.
The portion of this block which is inside the fork-end is preferably in the
form of a saddle or arch, for receiving the end of the wheel axle and the portion
on the outside of the fork-end, is in the form of a washer for receiving a bolt
which is screwed into the end of the axle.
We may secure the chain adjusting bolt to the block, and adjust by means
of a nut having a flange. The flange of the nut is held in position against the
fork-end by means of an end plate rivetted to the fork-end. Or, we may pass
an adjusting bolt through the upper and inner part of the block which has a
hole tapped to receive it.
We may make the saddle portion of the block seperate from. the washer,
and form a ridge on the fork-end, to bear on the saddle, or, the ridge may be
supported directly on the axle, and the chain adjusted by the usual form of
chain adjuster.
When the bolts which are screwed into the wheel axle are withdrawn, the
wheel is free to be lifted out.
•
Dated this 8th day of a
improvements in and relating to the Chain Adjustment of Cycles.
JOHN BOYD DUNLOP and JOHN BOYD DUNLOP, Junior, Ailesbury Road, Dublin.
Gentlemen. 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: -
The object of this invention is to produce a simple device, for adjusting the
chain of a cycle, which permits of the driving wheel being easily removed
without interfering with the adjustment of the chain.
The fork end may be of the usual form. The wheel axle is short and its ends
[Price 8d.]

page_text: are drilled and tapped. Preferably, a metal block is provided which is adapted
to slide in the slot of the fork end. Preferably, the portion of this block
which is inside of the fork end is in the form of a saddle or arch, for receiving
the end of the wheel axle, and the portion on the outside of the fork end, is
in the form of a washer for receiving a bolt which is screwed into the end of
the axle and which locks the axle, or cone on the axle, against the inner face
of the fork end. The chain adjusting nut, as usual, screws on a bolt which is
secured to the block. The chain adjusting nut has a flange which is held
between the fork end, and an end plate which is rivetted to the fork end, and
the chain adjusting nut is thus prevented from moving backward or forward.
We may, in some cases, pass the adjusting bolt through a tapped hole in the
inner and upper part of the block.
We may make the saddle portion of the block seperate from the washer
portion. We may form a ridge on the fork end to bear on the saddle, or, the
ridge may bear directly on the wheel axle, and the chain may be adjusted by
the usual chain adjusting eye bolt.
In all cases we lock the block, or chain adjusting eye bolt, and the axle,
by means of a bolt screwed into the axle. When the bolt is withdrawn from
the axle the wheel is free to be lifted. or dropped, from the fork end.
In the accompanying drawings, which illustrate various forms of our invention,
Figure 1 is a side elevation, Figure 2 is a vertical section of Figure 1, on
the line 2-2, and Figure 3 is a perspective view of the block and chain
adjusting bolt, shown in Figures 1 and 2.
Figures 4 and 5 are perspective views, and Figure 6 is a vertical section of
another form of block.
Figure 7 is a vertical section, and Figure 8 is a side elevation, of another
form of block in position. Figure 9 is a seperate perspective view of the
block shown in Figures 7 and 8.
Figure 10 is a vertical section illustrating another form of our invention,
in which a ridge on the fork end bears directly on the wheel axle.
Like letters indicate like parts in the drawings.
A is a portion of the seat stay, and A¹ is a portion of the chain stay, joined
to the fork end B.
C is the block and chain adjusting bolt, C¹ is the block, and C is the chain
adjusting bolt.
"
C3 is the saddle shaped portion of the block C¹.
Care slots to receive the slotted fork end B.
C in Figures and 2 is the washer shaped portion of the block C¹, and
C in Figure 10, is the washer or eye of an ordinary chain adjusting bolt.
D is the wheel axle which is tapped to receive the bolt E.
F is the end plate rivetted to the fork end B. and G is a recess in the fork
end to accommodate the flange H¹ on the nut H.
In Figures 4, 5 & 6 the bolt E bears directly on the fork end, and the washer
portion C is dispensed with.
In Figures 7, 8 and 9 the ridge B₁ rests on the block C¹ which bears against
the inner face of the fork end B.
In Figure 10 the ridge B¹ rests directly on the wheel axle which bears against
the inner face of the fork end B.
In the drawings, the cone is shown solid with the wheel axle, but the cone
may be screwed on the axle, and the wheel bearing may be either cup, or
cone, adjusting.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is:
-
1. In a cycle, a block having a saddle shaped portion such as C³, for receiving
the end of the wheel axle, or cone and axle, substantially as described.

page_text: 2. In a cycle, a block having a saddle shaped portion such as C³, for receiving
the end of the wheel axle, or cone and axle, in combination with a bolt such
as E for the purpose described.
3. A ridge or shoulder such as B¹, on the inner side of a cycle fork end, in
combination with a block having a saddle shaped portion, such as C³,
illustrated in Figures 7, 8 and 9.
as
4. A ridge or shoulder such as B¹, on the inner side of a cycle fork end, in
combination with a wheel axle, and a bolt such as E, as illustrated in Figure 10.
5. In a cycle, a non-detachable nut such as H, in combination with a non-
detachable block such as C¹, and a bolt such as E, for the purpose described.
Dated this Eighth day of June 1900.
JOHN BOYD DUNLOP,
JOHN BOYD DUNLOP, JUNIOR.