IMPROVEMENTS IN THE MANUFACTURE OF FILES BY MEANS OF MACHINERY FOR SMOOTHING AND CUTTING THEM
Year: 1866

page_text: LETTERS PATENT to Jorgen Balthazar Dalhoff, of Copenhagen, in the
Kingdom of Denmark, Goldsmith, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF FILES BY MEANS OF MACHINERY FOR SMOOTHING AND
CUTTING THEM."
Sealed-the 17th July 1866, and dated the 30th January 1866.
PROVISIONAL SPECIFICATION left by the said Jorgen Balthazar Dalhoff
at the Office of the Commissioners of Patents, with his Petition, on the
30th January 1866.
I, JORGEN BALTHAZAR DALHOFF, of Copenhagen, in the Kingdom of
Denmark, Goldsmith, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF FILES BY MEANS OF MACHINEKY FOR
SMOOTHING AND CUTTING THEM," to be as follows:-
My improvements consist, firstly, in smoothing the surface of the file by
means of a planing machine previous to cutting it. The file is moved per-
pendicularly up and down between two planes placed under water and
approaching each other according to.the thickness of the file. The planes at
the same time are moving sideways to and fro on the surface of the file in
alternately oblique directions corresponding with the directions of the cuts.
By this process the file receives a smoother and more even surface than can
be obtained by filing or grinding, and a perfectly straight chisel will fit every
part of the file. even where it is bellied. This planing machine consists of a
Price 81

page_text: box containing water and having two elevated side beams of wood to form
the frame, at the top of which is the main axle by which the machine is set
in motion. At one end of this axle is an arm, which in revolving, moves a
slide perpendicularly up and down. The file is attached to the lower end of
the slide and reaches down into the water where the two planes are placed.
When the machine is in motion the file will then move up and down
between the two planes. Each plane consists of an inner and outer box, the
inner one contains a number of straight sharp knives and rests on a tap
passing through a hole in the outer one, this tap serves to turn the knives in
different oblique directions within the outer box. To effect this movement a
wheel is employed, which by means of a strap round the main axle is put
into a slow motion, on the outer edge of the wheel is a raised rim running in
a serpentine line from one side of the wheel to the other, and pressing on
rollers attached to an iron frame, which by the revolution of the wheel is moved
horizontally backward and forward. This frame being connected with the
tap on the inner box of the plane will consequently when it moves turn the
inner box backwards and forwards within the outer one.
Secondly, in cutting the file an improved chisel holder is employed. It is
placed in a file-cutting machine in such a manner that it presses firmly against
the file before the stroke takes place, and consists of a massive piece of metal
with one side forming a slope upon which the chisel rests, and a hoop by
means of which the chisel is pressed firmly against the slope; between the
hoop and the chisel is placed a moveable plate with a pointed tap that receives
the whole pressure, and thus the chisel is able to turn according to the shape
of the file. By means of a screw the hoop and the chisel can be moved
backwards and forwards even during the process of cutting. By this com-
bination it is possible to make both the first and second cuts of a file by the
same machine as it is only necessary to change the position of the chisel holder.
The haminer strikes perpendicularly down on the chisel while it rests in the
sloping position.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jorgen Balthazar Dalhoff in the Great Seal Patent Office on
the 18th July 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JORGEN
BALTHAZAR DALHOFF, of Copenhagen, in the Kingdom of Denmark, Goldsmith,
send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of January, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Jorgen Balthazar Dalhoff, Her special licence that I, the said Jorgen
Balthazar Dalhoff, my executors, administrators, and assigns, or such others as
1, the said Jorgen Balthazar Dalhoff, my executors, 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 THE MANUFACTURE OF FILES BY MEANS OF MACHINERY FOR
SMOOTHING AND CUTTING THEM," upon the condition (amongst others) that I,
the said Jorgen Balthazar Dalhoff, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and scals,
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 Jorgen Balthazar Dalhoff, 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 :-
Firstly, a machine to smooth the file before cutting it. The file is moved
perpendicularly up and down between two planes placed under water and oil,
and able to approach each other according to the thickness of the file, the
planes at the same time are turning sideways to and fro on the surface of the
file alternately in the two oblique directions which the teeth will have. This
operation regard as absolutely necessary to the successful cutting of a file
by means of machinery as it enables the same chisel to fit every part of a file
whether bellied or not.
On the accompanying Drawings, Fig. 1 is a side view of the machine;
Fig. 2, end view; Fig. 3, bird's-eye view; Fig. 4, a and b, the outer box
of the plane; Fig. 5, a and b, the plane with its knives. The same objects
represented in the different Drawings are indicated with the same letters.
A, a water-tight box with two compartments; B, two sidebeams of wood;
C, the main moving axle; D, an arm, which when it revolves moves a piece
of wood d in a slide, and the file c up and down: E, two planes: they consist
of an outer box, Fig. 4, a and b, with two half round taps c. by which they

page_text: are suspended, and an inner box. Fig. 5, a and b, with a number of knives.
This box is at the back provided with a tap c, which passes through the hole d
in the bottom of the outer box, this tap c serves to turn the inner box con-
taining the knives in different oblique directions. In the bottom of the inner
box under the knives is introduced an india-rubber plate, and for rough
planing a plate of lead may be placed between each of the knives. One of
these planes can also be used separately without the machine to smooth the
file. F, two axles, each with two arms b' at the top provided with beds in
which the half round taps e' of the planes rest; b two other arms proceeding
from the same axle F, but crossing each other and extending in a bend line
to outside the opposite side of the water reservoir, at the end of each of
these arms is placed a weight b, and thus the planes are pressed against the
file; bare two counterweights to keep the planes in balance. G, a wheel
which by means of a strap around the axle C is put into a slow motion. The
wheel is on its periphery provided with a raised rim grunning in a serpentine
line from one side of the wheel to the other. Han iron frame provided with
rollers running on iron rails, and two erect standing rollers h³, which when
the wheel G revolves receive the pressure of the rim g and draw the frame
forward and backward. On the frame are two bars i each at its opposite end
fitted to a small arm connected with the tap (Fig. 5, c²). The horizontal
motion of the frame G will thus cause the inner box with the knives to be
turned to and fro by its tap.
Secondly, a chisel holder (Fig. 6), placed in a file-cutting machine in such
a manner that it presses firmly against the file before the stroke takes place.
Fig. 6 represents a sectional, a birds'-eye, and a side view of the chisel holder.
a, a massive piece of metal with a slope in the direction the chisel ought to
stand, and upon which the chisel rests; b, the chisel, having a point of support
at the top and one at the bottom, with an open space in the middle; c, a hoop
holding the chisel firmly by means of a screw; between the chisel and the
screw is placed a round plate with a pointed top and an india-rubber plate,
enabling the chisel easily to turn according to the form of the file, and causing
an elastic but firm pressure on the chisel against the chisel holder. At one
end of the hoop c is a screw d, by which the chisel and hoop can even during
the process of cutting be moved to either side if the chisel cuts harder in one
side than in the other. The chisel holder is modified according to the file
required; for cutting common files it is used as described above, but for files
required to be very deep with sharp teeth not bending back the lower support
of the chisel is sloped as e, and the chisel has a rounded form at the same place
besides being on the whole of its back somewhat round. This makes. the motion

page_text: of the chisel during the cutting more certain, and it is possible to determine
precisely the form of the teeth, particularly when the chisel has on its edge a
small facet as indicated by the line 1, 2, a fork f, and a small lever g, which
by means of a screw presses upon the fork. hold the chisel in the required
depth, and prevent it sliding upward after the stroke. In cutting files of
various kinds where the teeth are required to rise more or less, the chisel rests
with its back against a semicircular piece of metal introduced in the chisel
holder; this piece of metal has a tap i moving up and down in a slide-in-the
chisel holder and pressing against a screw that is regulated according as the
chisel is wanted to stand more or less perpendicularly on the file.
Having thus described the nature of my Invention I declare that what I
claim is as follows:-
1. That the knives in the planes which smooth the file stand with their
edge in the same oblique direction on the file as the chisel occupies when
cutting it, and the chisel will thus fit every part, as the knives remove all
unevenness and give the file a uniform rounding all over.
2. That it, by means of the chisel holder, is possible absolutely and precisely
to determine the form which the teeth will receive in the cutting. namely.
in cutting common files the chisel rests on two sloping points of support with
a flat surface on a flat surface, but if the teeth are required to rise more, yet
without having their points bent back, then the lower point of support slopes
outward and the chisel has a roundish form on the back, thus receiving
an arched motion, and when files of different kinds are to be cut the chisel
rests on a loose piece of metal semicircular at the back and able to move in
the necessary arched line: by a screw in the chisel holder the position of
the chisel against the file, and consequently the depth and rise of the teeth
may he regulated.
In witness whereof. I, the said Jorgen Balthazar Dalhoff, have hereunto
set my hand and seal, this Eighteenth day of July, One thousand
eight hundred and sixty-six.
JORGEN BALTHAZAR DALHOFF. (L.S.)