AN IMPROVED MILLSTONE DRESSING MACHINE
Year: 1875

page_text: LETTERS PATENT. to John Whittingham, of the Cross, Willaston,
Nantwich, in the County of Chester, Civil Engineer, for the Inven-
tion of "AN IMPROVED MILLSTONE DRESSING MACHINE."
PROVISIONAL SPECIFICATION left by the said John Whittingham at
the Office of the Commissioners of Patents, with his Petition, on
the 15th May 1875.
I, JOHN WHITTINGHAM, of the Cross, Willaston, Nantwich, in the
County of Chester, Civil Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVED MILLSTONE DRESSING MACHINE," to be
as follows:-
This Invention has for its object an improved millstone dressing
machine, and relates to an arrangement of apparatus designed to be
carried by a slide rest, which may be placed upon the face of the mill-
stone to be operated upon, and will enable the dressing tool to be moved
as required over the surface of the stone to be dressed. The dressing,

page_text: tool or chisel is fixed on a shaft or bar, one end of which is carried by a
spring attached to the frame of the machine, so that the shaft or bar
may be allowed to vibrate in the ordinary manner. The tool shaft or
bar passes through a slot or opening in a depending rod, whose upper
end is carried by a crank pin. The crank shaft being caused to rotate
gives an upward and downward movement to the depending rod. Within
the slot or opening in the rod is fixed a spring, which projects beyond
the rod and lies under, the tool shaft or bar. Motion being com-
municated to the crank shaft by gearing or otherwise an upward and
downward movement is thus communicated through the depending rod
and its spring to the shaft or bar carrying the dressing tool or chisel,
which is thereby caused to vibrate as required for operating upon the
stone to be dressed. The strength of blow is regulated by moving
the tool shaft or bar through the slot or opening in the depending rod,
and by a slide beneath the tool shaft or bar near the tool, such slide
being arranged with an incline, and carrying a cushion of india-rubber
or similar material, so that the strength of blow can be regulated to a
great nicety.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said John Whittingham in the Great Seal Patent Office 2
on the 15th November 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WHITTINGHAM, of the Cross, Willaston, Nantwich, in the County of
Chester, Civil Engineer, send greeting.
'
WHEREAS Her most Excellent Majesty Queen Victoria, by Hor 2
Letters Patent, bearing date the Fifteenth day of May, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John Whittingham, Her special
licence, that I, the said John Whittingham, my executors, adminis- 3
trators, and assigns, or such others as I, the said John Whittingham,
my exccutors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter
during the term therein expressed, should. and lawfully might make,

page_text: use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention
for "AN IMPROVED MILLSTONE DRESSING MACHINE," upon the condition
(amongst others) that I, the said John Whittingham, my executors or
administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said John Whittingham, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, and the accompanying Sheet
of Drawings therein referred to (that is to say) :-
This Invention has for its object an improved millstone dressing
machine, and relates to an arrangement of apparatus designed to be
carried by a slide rest, which may be placed upon the face of the mill-
stone to be operated upon, and will enable the dressing tool to be moved
as required over the surface of the stone to be dressed. The dressing
tool or chisel is fixed on a shaft or bar, one end of which is carried by a
spring or pivot attached to the frame of the machine, so that the shaft
The tool
or bar may be allowed to vibrate in the ordinary manner.
shaft or bar passes through a slot or opening in a depending rod, whose
5 upper end is carried by a crank pin. The crank shaft being caused to
rotate gives an upward and downward movement to the depending rod.
Within the slot or opening in the rod is fixed a spring, which projects
beyond the rod, and lies under the tool shaft or bar. Motion being
communicated to the crank shaft by gearing or otherwise an upward
o and downward movement is thus communicated through the depending
rod and its spring to the shaft or bar carrying the dressing tool or chisel,
which is thereby caused to vibrate as required for operating upon
the stone to be dressed. The strength of blow may be regulated by
moving the tool shaft or bar through the slot or opening in the
5 depending rod and by a slide beneath the tool shaft or bar near the
tool
.

page_text: Fig. 1 of the Drawings shews in side elevation a stone dressing machine
embodying my improvements; Fig. 2 is an end elevation at right angles
to Fig. 1; Fig. 3 is a plan.
a is the bed of the machine, which is placed on the stone to be dressed;
b is the slide rest arranged to be moved along the bed as required by a
rack and pinion, as shewn. On the slide rest 6 is carried a transverse
slide o, on which are two frames c', c³, arranged to be moved by a screw d
upon the slide rest 6, as required, to regulate the distance between the
groove to be cut in the stone. The frames c², c², carry the crank shaft e
operated by a handle through gearing g, and provided with a small fly
wheel o weighted at one side to balance the dressing tool and its shaft;
h is the dressing tool or chisel; i, the shaft or bar on which it is fixed;
this shaft or bar vibrates on a pin i¹, which pin is secured in a slot k to
the frame by means of a screw and nut ; this arrangement is for the
purpose of adjusting the tool as it wears away. The tool shaft or bar
may be carried by a flat spring, forming a sort of continuation of the
shaft or bar, so as to allow the latter to vibrate as required, but I prefer
the arrangement shewn in the Drawing, because I find in working a
spring is liable to fracture, and the machine works equally well without
the spring, the shaft merely vibrating on a pivot, as shewn; m is the
depending rod, whose upper end is carried by the crank pin; this rod is
formed with a slot at n, through which the tool shaft or bar passes; p is
a spring fixed within the slot and lying under the tool shaft or bar for
the purpose already explained. The machine thus constructed operates
in the manner herein-before described.
Having described the nature of my said Invention, and explained the
manner of carrying it into practical effect, I hereby declare that I do not
claim as of my Invention or the exclusive use of any of the individual
parts composing the machine herein-before described; but what I
consider to be novel and original and therefore claim as the Invention &
secured to me by the herein-before in part recited Letters Patent is,―
The actuating the tool shaft or bar by means of a rod and spring, said
spring being interposed between the tool shaft or bar and the rod to
enable a dead blow to be given by the tool to the stone, as above set
forth.
2

page_text: I also claim the combination of parts constituting the improved mill-
stone dressing machine, constructed, arranged, and operating as shewn
in and described with reference to the accompanying Sheet of Drawings.
In witness whereof, I, the said John Whittingham, have hereunto
set my hand and seal, this Eleventh day of November, in the
year of our Lord One thousand eight hundred and seventy-five.