NEW OR IMPROVED MACHINERY FOR GRINDING CURLING STONES
Year: 1881

page_text: LETTERS PATENT to Andrew Kay, of the Firm of T. and A. Kay, of Haugh,
Mauchline, in the County of Ayr, North Britain, Curling Stone Manu-
facturers, for an Invention of "NEW OR IMPROVED MACHINERY FOR GRINDING
CURLING STONES."
PROVISIONAL SPECIFICATION left by the said Andrew Kay at the Office
of the Commissioners of Patents on the 13th October 1881.
"NEW OR
ANDREW KAY, of the Firm of T. and A. Kay, of Haugh, Mauchline, in the
County of Ayr, North Britain, Curling Stone Manufacturers.
IMPROVED MACHINERY FOR GRINDING CURLING STONES."
The said Invention relates to new or improved machinery for grinding curling
stones, and consists as follows:-A cylindrical grinding surface is provided of
free-stone, or other suitable grinding material mounted upon a shaft or axis carried
in suitable bearings, so that it is capable of being rotated and also of being drawn
endways by a screw or its equivalent. This grinding surface is of larger diameter
at one part than at the other, the said grinding surface at the junction of the parts
of larger and smaller diameter being of a curved figure corresponding to the curve,
of the curling stone as seen from the side. In bearings above the grinding surface
is a shaft at right angles to the axis of the said grinding surface, and set slightly to
one side of the said axis, that is to say, not being in the same vertical plane, and
having at its lower end an enclosing ring or cup in which the curling stone to be
ground is carried. Motion of rotation is given to this shaft, which may be effected
by bevel gearing, the bevel wheel on the said shaft being connected thereto by a
groove and feather, so that the said shaft may be raised and lowered without
affecting the position of the said wheel. A weighted lever is attached to the end
of this shaft to give the necessary forcible contact of the curling stone being ground
with this grinding surface. A cord attached to this lever and led over pulleys to a
convenient position serves as a means for raising the shaft when the stone is to be
removed from the ring or cup at its end. When the machine is in operation the
D

page_text: curling stone to be ground is placed in the ring or cup before mentioned, the shaft
carrying the said ring or cup being raised for this purpose. The said shaft is then
lowered and the curling stone is pressed by the weighted lever upon the cylindrical
grinding surface, so that its rounded edge is seated in the corresponding curve of
the said grinding surface. Motion of rotation is given to the shaft carrying the
curling stone and to that carrying the grinding surface, so that the said stone and
grinding surface at the part being ground travel in reverse directions. When the
curling stone is sufficiently ground on the one side (top or bottom) it is reversed in
its holding ring, and the other side is similarly ground. The part of the grinding
surface of smaller diameter, whereon the curling stone rests, and which is close to
the curved junction with the part of the said grinding surface of larger diameter, is
preferably inclined downwards or inwards towards the said curved portion, so that
the curling stone is inclined slightly downwards towards the side at which the
grinding of its curved portion takes place. As the grinding surface wears
longitudinally it is adjusted by the before mentioned screw, which moves it end-
ways towards the curling stone. As the grinding surface is worn down towards its
centre, the part of larger diameter is or may be kept at the proper distance above
the part of smaller diameter by being cut down by suitable tools, either worked by
hand or attached to the machine, so as to automatically trim down the said part of
larger diameter to the proper extent.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Andrew Kay in the Great Seal Patent Office on the 12th April
1882.
ANDREW KAY, of the Firm of T. and A. Kay, of Haugh, Mauchline, in the
County of Ayr, North Britain, Curling Stone Manufacturers.
"NEW OR
IMPROVED MACHINERY FOR GRINDING CURLING STONES."
My said Invention relates to new or improved machinery for grinding curling
stones, and consists as follows:-A grinding surface is provided of free stone or
other suitable grinding material mounted upon a shaft or axis carried in suitable
bearings, so that it is capable of being rotated and also of being drawn endwise by
a screw or its equivalent. This grinding surface is of larger diameter at one part
than at the other, the said grinding surface at the junction of the parts of larger
and smaller diameter being of a curved figure corresponding to the curve of the
curling stone as seen from the side. In bearings above the grinding surface is a
shaft at right angles to the axis of the said grinding surface, and set slightly to one
side of the said axis, that is to say, not being in the same vertical plane, and
baving at its lower end an enclosing ring or cup in which the curling stone to be
ground is carried. Motion of rotation in an opposite direction to that of the
grinding surface is given to this shaft which may be effected by bevel gearing, the
bevel wheel on the said shaft being connected thereto by a groove and feather, so
that the said shaft may be raised and lowered without affecting the position of the
said wheel. A weighted lever is attached to the end of this shaft to give the
necessary force of contact of the curling stone being ground with the grinding
surface. A cord attached to this lever and led over pulleys to a convenient
position serves as a means for raising the shaft when the stone is to be removed
from the ring or cup at its end.
And in order that my said Invention may be properly understood, I now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, reference being had to
the annexed Drawing, and to the letters and figures marked thereon, that is. to
say,-
The Drawing represents in side elevation apparatus constructed according to my
said Invention. The grinding surface or stone A is mounted and secured by
wedges, or in any other suitable manner, upon a shaft a carried in bearings a¹
supported in a wall, block, or other fixture Z, as shewn also in bearings a¹*
supported by a standard a bolted to the floor, or the bearings may be supported in
any other suitable or convenient manner. The shaft a carrying the stone A is
caused to be rotated by the pulley a³, and it is also capable of being moved in a
horizontal direction by a screw B carried in a bearing or nut 6 which is supported
by the standard b¹ bolted to the floor. The said screw B is operated by the hand
lever 62 keyed or otherwise secured to the one extremity of the said screw, the
opposite extremity of the same being provided with a collar free to rotate within a
box portion 63 secured upon the end of the shaft a, within which box portion the
extremity of the screw B is locked or prevented from being withdrawn.
The grinding surface of the stone A, as shewn, is of larger diameter at one part x
than at the other part 1, the said grinding surface at the junction of the parts of
the larger and smaller diameter being of a curved form, as at 2.
In bearings c carried by brackets c¹ mounted at the side of the wall or other
part Z is the vertical shaft C, which actuates the curling stone D which is to

page_text: The said shaft C is
be ground into shape upon the cylindrical grinding stone A.
mounted at right angles to the axis of the grinding surface A, and is preferably set
slightly to one side of the axis of the grinding surface A, that is to say, not in
the same vertical plane.
An encircling ring or cup E is keyed upon the lower extremity of the shaft C,
8, the top
the said ring being preferably constructed with several claws or arms
portions of which at e¹ bear upon the top of the curling stone D, whereby the
said stone when rotated is prevented from slipping out of the grip of the ring
or cup.
Motion of rotation in an opposite direction to that of the grinding surface A is
given to the shaft C by the bevel wheels F, F1, the wheel F being keyed upon the
horizontal short shaft carried in bearings in portions of the brackets c³, the said
The bevel
shaft f being rotated by the fixed pulley of the pair of pulleys f¹.
wheel F gears with the bevel wheel F¹. The wheel F' is keyed upon the shaft C
by a feather fitting in a key-way in the said shaft, and so that the shaft C is
capable of being raised or lowered without affecting the position of the bevel
wheel F¹.
In order to give the necessary force of contact of the curling stone being
ground with the grinding surface a lever G is centered upon a pin held within
adjustable holes formed in a bracket g held against the side of the wall or other
attachment Z.
The free extremity of the lever G has suspended from it weights g¹, which
weights produce a downward pressure upon the shaft C in the following manner:-
A rigid frame consisting of an upper and lower part h, h', connected together by
the two rods or screws h³ is fitted upon the extremity of the shaft C, being secured
thereto by the screwed centre h, the attachment being such that the shaft C is
free to revolve within the part h¹.
The said centre h is screwed into the extremity of the shaft C, which is so
formed as to secure or hold in position the lower part h¹, and leaves the shaft free
to rotate and its centre h* to abut accurately against the centre of a short shaft or
rod C, which is rigidly attached to or forms part of the upper portion h¹, the
said rod C¹ being attached to the lever G by a pin and slot g³. The weight to
bear upon the curling stone in course of being ground is imposed upon the shaft C
without undue friction, thus enabling the machine to work with freedom.
In order to raise the shaft C when the curling stone is to be removed from the
ring or cup at its end, a cord attached to the lever G, and led over pulleys to a
convenient position, may be employed, or any other suitable and convenient
arrangement may be adapted to effect the raising of the shaft C.
.
When the machine is in operation the curling stone to be ground is placed in
the ring or cup E, the shaft C carrying the said ring or cup being raised for this
purpose. The said shaft is then lowered, and the curling stone is pressed by the
weighted lever G upon the grinding surface of the stone A, so that its rounded edge
Motion of
is seated in the corresponding curve of the said grinding surface.
rotation is given to the shaft C carrying the curling stone D, and to that carrying
the grinding surface, so that the said stone and grinding surface at the part being
ground travel in reverse directions. When the curling stone is sufficiently ground
on the one side (top or bottom) it is reversed in its holding ring and the other
side is similarly ground. The part of the grinding surface of smaller diameter
whereon the curling stone rests, and which is close to the curved junction with the
part of the said grinding surface of larger diameter, is preferably inclined slightly
downwards or inwards towards the said curved portion, so that the curling stone
is inclined slightly downwards towards the side at which the grinding of its curved
portion takes place. As the grinding surface wears longitudinally it is adjusted
by the screw B, which moves it endwise towards the curling stone.
grinding surface is worn down towards its centre the part of larger diameter is or
may be kept at the proper distance above the part of smaller diameter by being
As the

page_text: cut down by suitable tools either worked by hand or attached to the machine so
as to automatically trim down the said part of larger diameter to the proper
extent.
Having now described and particularly ascertained the nature of my said
Invention, and the system, mode, or manner in or under which the same is or
may be used or practically carried into effect, I would observe in conclusion that
what I consider to be novel and original, and therefore claim as the Invention
secured to me by the hereinbefore in part recited Letters Patent is,―
First. The general arrangement and combination of parts constituting the
mechanism for producing curling stones of the requisite shape, substantially as
hereinbefore described and shewn upon the accompanying Sheet of Drawings.
Second. The arrangement of a grindstone revolving at right angles to the axis
of revolution of the curling stone, the grindstone being so shaped that the rotation
of the grindstone produces the requisite grinding and contour of the curling
stone, as herein before described and shewn upon the annexed Sheet of Drawings.
Third. The employment of a screw or its equivalent for maintaining the grind-
stone and curling stone in the requisite contact, and so as to ensure the continuous
wear of the grindstone as nearly as possible in continuous contour, as hereinbefore
described and shewn upon the annexed Sheet of Drawings.
In witness whereof, I, the said Andrew Kay, have hereunto set my hand
and seal, this Tenth day of April, in the year of our Lord One thousand
eight hundred and eighty two.