Improvements in or relating to Sprocket Wheels.
Year: 1899

page_text: Date of Application, 22nd Sept., 1899-Accepted, 28th Oct., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to Sprocket Wheels.
"
I, GUSTAV RIESELER, of "Burgia Cycle Works, Burg, near Magdeburg, in the
Empire of Germany, 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 present invention relates to a sprocket wheel particularly adapted for
cycles upon which it is impossible for the chain to jump or slip, thereby causing
accidents which may produce very serious consequences, especially on bad roads,
not the least of which is the harm caused to the cycle. This object is obtained
by employing loose teeth and arranging them in such a manner that they are
pressed forward by springs fixed in the rim of the wheel itself.
By way of example the invention is represented in the accompanying
drawing:-
―
Figures 1 and 2 represent two different constructions both in longitudinal
section.
Figure 3 is a vertical cross-section, and
Figure 4 is a horizontal section.
In the wheel rim a, which is either cast in one with the wheel itself, Figure 1,
or fastened to the main portion as represented in Figure 2, are provided radial
borings or holes, the inner width of which is not of uniform dimensions, but is
so formed as to make a kind of seat or abutment at the outer limit of the ring.
Into these openings are placed the teeth b from the inside, which teeth are
pressed through and against the periphery of the wheel by spring c secured in
the interior of the borings between the lower part of the tooth and a pin d
(Figure 1), or a ring or plate e screwed on to the inner side of the rim as repre-
sented in Figure 2. The part of the tooth within the rim a is somewhat wider
than the part projecting out of it, and forms a kind of abutment for the purpose
of preventing the tooth from being pushed out altogether. The outer end of the
tooth, intended to gear with the chain f is rounded off towards the top.
The effect of this arrangement of teeth may be explained in the following
manner: When the chain f has become somewhat worn in such a manner that
the length of the links no longer corresponds with the exact distances between
adjacent teeth, the pins connecting the links may come in contact or engage with
the head of a tooth while the teeth cease to uniformly engage with the chain.
According to this invention however the teeth 6 being actuated by springs and
being provided with rounded off heads will be forced somewhat out of the
ring a, the difference between the teeth actuating the chain f, becoming adjusted
to the width of the links of the chain so that they are always uniformly engaged.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. A sprocket wheel in which the teeth are not formed in one with the rim
but are radially and movably arranged in the rim being pressed outwards by

page_text: springs, and their heads being rounded off so that, when lateral pressure is
exerted by the chain links the heads will penetrate into the spaces whenever
the chain has become lengthened, thereby adjusting thmselves to the length of
the links, substantially as described.
T
2. The complete sprocket wheel rim construction, substantially as described
or illustrated in the accompanying drawings. -
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