IMPROVEMENTS IN APPARATUS FOR EXERTING PRESSURE OR POWER BY MEANS OF SCREWS, APPLICABLE TO SCREW PRESSES
Year: 1875

page_text: LETTERS PATENT to Richard Olpherts, of Ardee, in the County of
Louth, Ireland, for the Invention of "IMPROVEMENTS IN APPARATUS
FOR EXERTING PRESSURE OR POWER BY MEANS OF SCREWS,
APPLICABLE TO SCREW PRESSES."
SPECIALLY
Sealed the 9th April 1875, and dated the 16th February 1875.
PROVISIONAL SPECIFICATION left by the said Richard Olpherts at
the Office of the Commissioners of Patents, with his Petition, on
the 16th February 1875.
I, RICHARD OLPHERTS, of Ardee, in the County of Louth, Ireland,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN APPARATUS FOR EXERTING PRESSURE OR POWER BY MEANS OF SCREWS, SPECIALLY
APPLICABLE TO SCREW PRESSES," to be as follows:-
-
In screw presses in which the press beam or girder is lowered or
raised on stationary screw shafts by means of nuts or worm wheels
made to rotate on the said shafts there is always great friction between
these nuts or worm wheels and the beam or girder or washer plates
placed thereon. And in presses where the screw shafts are made to

page_text: are
rotate there is always great friction between the beam or girder and the
collars or other devices fixed to the shafts to prevent them being pulled
through the beam. Again in other apparatus where screws
employed for the purpose of effecting pressure or power screw railway
brakes for example, there is similar friction between the piece in which
the screw works and the collar fixed to the screw to prevent it being
pulled through such piece.
Now the object of my Invention is to diminish this friction, and the
improvements consist in the employment for the purpose of rollers or
other like antifriction devices as herein-after described.
In presses or other apparatus where nuts or worm wheels are caused
to rotate in order to lower or raise a beam or the like on stationary
screw shafts, I place these rollers between the nuts and the beam. I
mount the rollers on radial axles held in an outer and an inner ring, and
they may with advantage be formed with one or more shoulders which:
work in grooves cut respectively in the lower bosses of the nuts and in
washer plates above the beam.
In presses or other apparatus where the screw shafts are made to
rotate the rollers are placed between the beam or corresponding part
and the collars or other devices employed on the screw shafts to prevent
the shafts being pulled through the beam.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Richard Olpherts in the Great Seal Patent Office
on the 13th August 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
OLPHERTS, of Ardee, in the County of Louth, Ireland, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of February, 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 successors,
give and grant unto me, the said Richard Olpherts, Her special licence
that I, the said Richard Olpherts, my executors, administrators, and
assigns, or such others as I, the said Richard Olpherts, my executors,

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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, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
APPARATUS FOR EXERTING PRESSURE OR POWER BY MEANS OF SCREWS, SPECIALLY
APPLICABLE TO SCREW PRESSES," upon the condition (amongst others) that I,
the said Richard Olpherts, my executors or administrators, by an instru-
ment 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 Richard Olpherts, do hereby
declare the nature of my 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, reference being had to the
accompanying Drawings, that is to say :—
In screw presses in which the press beam or girder is lowered or
raised on stationary screw shafts by means of nuts or worm wheels
made to rotate on the said shafts there is always great friction between
these nuts or worm wheels and the beam or girder or washer plates
placed on the beam. And in presses where the screw shafts are made
to rotate there is always great friction between the beam or girder and
the collars or other devices fixed to the shafts to prevent them being
pulled through the beam.
Now the object of my Invention is to diminish this friction, and the
improvements consist in the employment for the purpose of rollers or
other like antifriction devices, as herein-after described.
In presses where nuts or worm wheels are caused to rotate in order to
lower or raise a beam or stationary screw shafts, I place these rollers
between the nuts and the beam. I mount the rollers on radial axles
held in an outer and an inner ring.
In
presses where the screw shafts are made to rotate the rollers are
placed between the beam and the collars or other devices employed

page_text: on the screw shafts to prevent the shafts being pulled through the
beam.
My Invention will be fully understood on reference to the accom-
panying Drawings.
Figure 1 is a vertical section of part of a screw press with rollers
applied thereto, as herein-before described; and Figure 2 is a plan of
the rollers and adjacent parts.
A is the beam or girder of the press; B is a stationary screw shaft
which passes through apertures formed in the beam, as shewn; two or
more of these shafts will be employed according to the size or
description of press. C is a nut fitting on the screw shaft B; D is
a worm or toothed wheel on the nut C, to which wheel rotary motion is
imparted by a tangent screw shaft, or otherwise. The exterior of the
nut O is of hexagonal or other suitable angular form, and the interior of
the wheel D is of corresponding form so as to fit thereon and turn the
nut, or the wheel and nut may be wedged or otherwise fixed to each
other so as to turn together; E, E, are the antifriction rollers upon
which the bottom or boss of the nut C rests. These rollers are mounted
on radial axles, which are held in an outer fixed ring F and an inner
fixed ring G: They are by preference of conical form, as shewn, the
cone being such that if extended its point would be in the centre of the
screw shaft B. H is a plate upon which the rollers bear, part of this
plate being inclined to correspond with the inclination or cone of
the rollers. I is another plate or washer between the plate H and
the beam A. K, K, are angle pieces to bear upon the upper side of the
boss of the nut. L, L, are bolts to secure the pieces K and plates H
and I to the beam.
It will be readily understood that when the nut C is caused to rotate
so as to lower the beam A on the screw shaft, the friction or thrust of
the bottom of the nut instead of being received as it would otherwise
be by the beam or by a washer on the beam is received by the rollers E,
and as these rollers are free to rotate on their axes the friction is con-
sequently much reduced.
The application of my Invention to presses in which the screw shafts
instead of being stationary, as in the arrangement just described, are
caused to rotate, will be understood by imagining the nut C, Figure 1,
to be a collar or head solid with the screw shaft, and acting so as to

page_text: prevent the shaft being pulled through the beam. The friction or
thrust which is usually received by the beam is received by the rollers
and is much reduced.
And having now described the nature of my said Invention, and in
what manner the same is to be performed, I declare that I claim, the
employment in presses where the pressure or power is exerted by means
of screws, of rollers, or analogous devices, substantially in the manner
and for the purpose herein-before described.
In witness whereof, I, the said Richard Olpherts, have hereunto
set my hand and seal, this Thirtieth day of July, One thousand
eight hundred and seventy-five.