IMPROVEMENTS IN ROLLER SKATES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by George Clark at the Office of the Com-
missioners of Patents on the 4th March 1870.
GEORGE CLARK, of No. 10, Craven Buildings, Drury Lane, in the County of
Middlesex. "IMPROVEMENTS IN ROLLER SKATES."
This Invention relates, firstly, to an improvement in the construction of roller
skates, whereby when the platform or footboard of a roller skate is made to pivot
and turn on the axles, or the axles are made to revolve under the platform or foot-
board, a radial novement and position are imparted to the axles of roller skates;
and regulated and controlled by means of springs connecting the axles to each
other, so that in the normal position of the axles with the springs so attached to
then they shall be parallel to each other, but shall be actuated and brought into a
radial position by means of the friction of the wheels inside any curve imparted to
the skate by the motions of the skater.
The method by which I carry the above mentioned plan into effect is to attach
the two axles to each other when in a parallel position, as above described, by
means of two or more metallic spiral springs a short distance apart from each other
longitudinally under the platform or footboard, each of the said spiral springs at the
time of their being attached to the axles to be stretched or drawn out to the extent
of about half the elastic force of the said spiral springs. The effect of this arrange-
ment is that the axles are fixed and maintained parallel to each other by the
drawing force of the springs, but they will radiate from the central line between the
two axles on one side or the other of the skate whenever the skates being in action
are by the force and direction of the skater's movements turned to one side or the
other. Without any mechanical fittings or contrivances to force or guide the axles
to take or assume any radial position the connecting of the axles to cach other with
and by means of spiral springs in the manner above mentioned and described,
whenever a turning or curvilinear motion is imparted to the skate by the skater, the
two axles will arrange themselves or be brought into a radial position, each in an
opposite direction, through and by means of the friction of the wheels on the inside
of the curve retarding their motion and bringing them nearer to each other, and
separating the wheels on the outside of the curve further apart from each other.
At any moment when by the motive action imparted to the skates in a curvi-
linear direction that motion is made to cease by the skater moving in a straight
line, the force of the springs which connect the two axles to each other will
CD11

page_text: instantly bring them into a parallel position. This contrivance for the purpose of
bringing the axles from a parallel to a radial position, or vice versa, may be said to
be a self-acting and reciprocating movement of the axles in opposite directions
exactly corresponding to each other.
Although I have described metallic spiral springs as suitable to carry my said
Invention into effect, any other kind of suitable metallic springs or india-rubber
springs, either alone or in combination with each other, may be made use of to effect
the object proposed by my said Invention.
My said Invention relates, secondly, to the use of other materials in lieu of or in
combination with wood for the rollers or wheels of roller skates. One material
which I propose for the purpose is porcelain or earthenware made of China clay or
fire-clay, or any other kind of clay suitable for porcelain or earthenware. I
propose to give to this material the necessary toughness and malleability to prevent
its breaking or chipping by pressure when in a plastic state, and annealing it with
oil or otherwise. Another material is glass, also rendered tough and malleable by a
process of annealing similar to that just above mentioned. A third material is soft
metal produced by the admixture in a fused state of lead, tin, zinc, bismuth, and
antimony, all or any of them in combination and in proportions to produce required
degree of hardness without being so hard as to cut or indent the skating surface.
A fourth material and combination is a ring of steel or other metal to be applied as
a tire outside a wheel of wood or of any other suitable material, for which papier
maché would be well adapted, with or without a thin band of india-rubber between
the metal tire and the wheel. To fix this tire round the wheel it would be
expanded by heat and passed over the circumference of the wheel, and be attached
thereto by contraction in cooling. The outside of the metallic ring should be
roughened to make it bite to the surface of the skating floor or pavement. A fifth
combination is the application of a band of india-rubber, felt, cloth, leather, or any
other yielding material, over and around the periphery of a wheel of wood or other
material, with a metallic spiral spring, or a split ring of elastic metal over the band
of india-rubber, or any other material. Such metallic spiral spring or ring will
form a tire to the wheel, and may be used alone without a band of india-rubber or
other yielding material.