Improvements in Velocipedes.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in Velocipedes.
I, JOHN JACOB MERLAIN, of South Bend, County of St. Joseph, and State or
Indiana, U.S.A., Gentleman, do hereby declare the nature of my invention for
IMPROVED SPRING FORKS FOR BICYCLES and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
. In the annexed drawings in duplicate :-
Figure 1 is a side elevation of a bicycle showing my improved spring supports
or forks. Figure 2 is a front view enlarged of the front spring fork as applied to
wheel. Figure 3 is a side view thereof enlarged. Figure 4 is a detail plan view
thereof. Figure 5 is a detail.
This invention is an improvement in bicycles and similar vehicles and its object is
to provide a spring support for the saddle bar and it consists in the peculiar
construction of the forks of the bicycle front or rear wheel, or both, said forks
consisting of bars rigidly connected at one point and adjustably connected at another
point by adjustable or yielding toggle joints, whereby weight superimposed upon the
said joint will distend or separate the bars and thereby utilize their resiliency to
cushion the saddle bar of the machine, all of which will be clearly understood from
the following description and claims :-
Figure 1 of the drawings shows a bicycle of the style known as "safety" machines,
having a front wheel Z, rear wheel Y, saddle bar X, treadle and seat. The front end
of the saddle bar is connected to the front wheel Z by means of my improved spring
fork which is constructed as follows:-
A designates a short shaft passing through the hub of either wheel Y or Z and
B, B, are angular journal blocks on the ends of said shaft exterior to the wheel, said
blocks being wedge-shaped, as shown; to the side faces of the blocks on the front
wheel are rigidly secured upstanding bars CD preferably of flat or strap spring metal,
and owing to the beveled sides of the blocks the free ends of the bars diverge. The
upper ends of the bars C, D, rise above the periphery of the wheel and are provided
with eyes c, d, respectively; hars C are in front of bars D but in line therewith.
E and F designate the leaves of the toggle joint; the leaf F has an eye f which
is embraced between two eyes e, e, of leaf E, and G designates a bolt passing
through said eyes and hinging the leaves together. H, H, designate outwardly
projecting diverging arms of leaf E, which are formed with eyes h, h, at their
extremities, through which passes a bolt I that also passes through eyes d, d, of
bars D, D, thus hinging the leaf to said bars. Leaf F is similarly formed with
projecting arms J, J, having eyes i, j, transfixed by a bolt K that passes through
eyes c, c, of bars C, as shown.
The toggle joint thus adjustably or flexibly connects the pairs of bars C, D, and
straddles the wheel as shown. The length of the leaves of the toggle joint is such
that it is kept normally partially closed, its central part, which is bolt G, standing
highest, and if any pressure is exerted to flatten the joint it will be resisted by the
resiliency of spring bars C, D, which will be distended or separated more or less
according to the greater or less opening and closing of joint. This will be apparent
from the drawings.
L designates a handle shaft attached to or formed with leaf F and rising therefrom,
and to the upper end thereof the ordinary steering handles can be secured. The front
end of the saddle bar X is loosely connected to said standard, as indicated in the
drawings, in any suitable manner. The rider can thus-turn-wheel Z to guide the
machine. The spring bars C, D, are preferably flat and laid edgewise to the wheel,
being coupled on both sides thereof, and they will hold the wheel firmly in a plane

page_text: relatively thereto, and will turn it therewith without vibration or torsional strain; their
elasticity will only affect the saddle bar in its vertical movements, and owing to their
peculiar connection therewith any sudden jolt or jar of the front wheel will cause the
toggle joint to distend the spring for the moment, and the natural resiliency of the
bars will permit the wheel to pass over obstructions without uncomfortably affecting
the rider. As applied to the front wheel Z both bars C, D, are elastic, but as applied
to the rear wheel a modification of this construction is desirable; in this the spring
fork lies horizontal to the ground but is connected to the wheel shaft as is the front
fork, and the toggle joint is connected directly to the saddle bar ✗ below the seat.
The member F of this fork corresponds to leaf F of the front fork and is rigidly
connected to the saddle bar, and the lowermost bars D₁ corresponding to bars D of
the front fork, are rigid or non-elastic, but are pivoted or hinged to F¹ as indicated
at f. The upper leaf E¹ is hinged to F¹ and is also hinged to the upper leaves C¹.
This construction has the effect of forcing C¹ upward while the centres or pivotal
point f, the axle of the wheel Y and the seat V hold a constant relative position
as regards each other. The ordinary spring under the seat will sometimes raise the
rider in rebounding, so as to throw his feet off the pedals; this cannot happen
with the spring forks as described. It should be understood that when one bar D¹
or is mentioned, its correspondent is understood as being on the opposite side
of the wheel, similarly to bars C and D.
In order to vary the resistance of the spring fork, or stiffen it, I employ an adjustable
clamp R, consisting of a loop r embracing the opposite bars C, D, as shown, and
adjustably secured in position on bar D by a set screw, while in its other end is an
adjustable screw R¹ the point of which bears against bar C. By shifting this loop
along the spring bars of the fork, the latter is stiffened as the bars can only be sprung
apart above the loop, and when the clamp is carried to the top of the fork the latter
becomes rigid.
I preferably use duplex pairs of spring bars and make the toggle joint double
armed, but in some instances the positions of the parts of the forks might be reversed.
That is the toggle joints might be mounted on the shafts, and the converging ends
of the spring bars be connected to the saddle bar. In either case it is evident that
the function and effect of the fork would be unaltered.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I.
claim is;-
1. In a fork for bicycles etc., the combination of opposite bars connected at their
converging ends; with a toggle joint consisting of two leaves hinged together and
connected respectively to the diverging ends of said bars, as and for the purpose set
forth.
2. In a fork for bicycles etc., the combination of opposite bars connected at their
converging ends, and the toggle joint having two leaves respectively united to the
diverging ends of said bars; with the adjustable clamp attached to said bars for
regulating the stiffness of the fork, substantially as specified.
3. The combination in a bicycle of the front and rear wheels, the saddle bar, the
pairs of diverging bars connected to the journal blocks on the axle of each wheel, and
on opposite sides of the wheels, and the double leaved toggle joints, each leaf of which
is connected to the outer or diverging ends of the similar bars of opposite pairs on
the same wheel, and the connections between one leaf of each joint and the saddle
bar, and the handle bar, all. constructed and arranged substantially as specified.
Dated this 91at don of t
1000