IMPROVEMENTS IN ROLLER SKATES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Henry Kesterton at the Office of the
Commissioners of Patents on the 24th April 1876.
HENRY KESTERTON, of Birmingham, in the County of Warwick, Mechanical
Engineer. "IMPROVEMENTS IN ROLLER SKATES."
My Invention consists in constructing and combining or arranging the parts of
roller skates in the manner herein-after described whereby the axes of the rollers
are made to incline to one another in one or other direction by the depression of
the fore end and heel end respectively of the skate, and the skater thereby enabled
to direct his path to the right or the left without any lateral inclining of the foot.
To the under side of the sole of the skate, and near the fore end, a strong quick
threaded screw is fixed perpendicular to the plane of the sole, and a similar threaded
screw is similarly fixed at the heel end of the skate. These quick threaded screws
engage in corresponding screw boxes in the bearings of the roller axes respectively.
Strong coiled springs surrounding the screws bear at their upper ends against the under
side of the sole, and at their lower ends on the horizontal arms of the bearings.
These springs are of such strength that the weight of the skater is borne by them
and through them by the bearings of the roller axes, there being no pressure on the
screws so long as the foot presses equally on both ends of the sole. The axes of the
rollers are parallel so long as the sole of the skate is horizontal, and this is the
normal state to which the parts always tend to return, and which they retain so
long as the pressure is equal on the fore and hind parts of the sole. When,
however, the skater depresses the fore part of his foot, and thereby relaxes the
pressure on the rear or hind part, the sole of the skate takes an inclined position,
the heel end rising and the fore end or toe end falling, and the coiled spring under
the fore part of the sole is compressed, and that under the rear part expands. The
result of this depressing of the front and raising of the rear end of the sole is to
force the screw at front into its screw box, and to raise that at back from its screw
box. But as the screws themselves are incapable of rotation the pressure on the
screws causes the screw boxes to turn upon the screws through a greater or less
angle, and as the screw boxes are part of or are fixed to the bearings of the axes
of the rollers, the angular motion of the screw boxes causes a like angular motion
of the axes of the rollers. The said axes are thus inclined to one another, and the
skate consequently takes a curvilinear path. When the heel is depressed and the
fore end of the foot raised a contrary inclination of the sole of the skate is produced,
and the screws operate upon their respective screw boxes in a direction opposite
to that already described. A turning of the screw boxes in a contrary direction
Dine 571

page_text: results, and consequently an inclination of the roller axes to one another in a
contrary direction. This is followed by the skate taking a curvilinear path in a
direction contrary to that it took by the contrary inclination of the sole. When
the skater ceases to exercise special pressure on either the heel or fore end of the
sole of the skate the coiled springs resume their balance, the sole of the skate 5
becomes horizontal, the axes of the skates become parallel, and the skate takes a
rectilinear path.