IMPROVEMENTS IN FRET SAWS
Year: 1863

page_text: LETTERS PATENT to Henri Adrien Bonneville, Patent Agent, of the
British and Foreign Patent Offices, 24, Rue du Mont Thabor, Paris,
in the Empire of France, and 38, Porchester Terrace, Bayswater, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN FRET
SAWS." A communication from Louis Pierre Nouvel, the younger,.
Morobent rosiding at Nantor in the Limoire of France aforesaid
COMPLETE SPECIFICATION filed by the said Henri Adrien Bonneville at the
Office of the Commissioners of Patents, with his Petition and Declaration,
on the 5th December 1863, pursuant to the 9th Section of the Patent
Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRI
ADRIEN BONNEVILLE, Patent Agent, of the British and Foreign Patent
Offices, 24, Rue du Mont Thabor, Paris, in the Empire of France, and
88, Porchester Terrace, Bayswater, in the County of Middlesex, send
greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN
FRET SAWS," communicated to me by Louis Pierre Nouvel, the younger,
Merchant, & person residing at Nantes, in the Empire of France, aforesaid,
and have petitioned Her Majesty to grant unto me, my executors, adminis

page_text: trators, and assigns, Her Royal Letters Patent for the same, and have made
solemn declaration that it is a communication.
NOW KNOW YE, that I, the said Henri Adrien Bonneville, do hereby
declare that the following Complete Specification under my hand and seal fully
describes and ascertains the nature of the said Invention, and the manner in
which the same is to be performed, reference being had to the accompanying
Drawings, in all the Figures of which the corresponding parts of the mechanism
are represented by the same letters, that is to say :-
This Invention consists in the construction of a pierce or fret sawing appa-
ratus, in which the saw may be made to follow the lines of the pattern instead
of, as in the ordinary apparatus, having a rising and descending movement only,
the improved apparatus having besides the advantage of working in either
way. For this purpose a frame A is mounted by two pivots on a fixed post,
which forms part of the framework supporting the whole of the apparatus, this
frame A carries on the side opposite to the pivots a round straight rod a.
Another frame B is articulated with the first by means of two journals, and
can besides rise and descend on the rod a. The frame A in turning around
the post causes the rod a to describe an arc of a cercle, producing a move-
ment in a direction perpendicular to the saw blade, the frame B in turning
around the rod a causes the saw blade which is placed on this frame on the
side opposite to the pivots to describe an arc, which produces a movement on
the same level as the former, but in a different direction. The saw is held at
each end by a clamp or vice, the lower clamp may turn in the lower branch
of the frame B, where it is held by a double screw nut and washer. The
upper clamp hangs on a rod, which is fixed at a variable height in a socket
forming part of a frame C. This frame is suspended to the upper arm of the
frame B, where it is held by a double screw nut and washer. It turns on its
centre, and turns with it a toothed wheel, which communicates by a band chain
with another toothed wheel fixed to an arbor d, turning on the other side of
the frame B. At the lower end of this arbor d another toothed wheel is fixed,
which communicates by a second band chain with a fourth toothed wheel
below the saw frame, so that if the frame C is turned, the lower clamp t will
turn at the same time to a similar angle. A plate D held horizontally and
at a fixed height by a bracket E jointed on the rod a, and which turns on itself
in a cercle which forms the prolongation of the bracket, is bored with two
holes fitted with brasses, in which pass the two uprights of the frame C. This
plate having the same axe of rotation on itself as the saw, and describing
besides the same cercle around the rod a, if it is made to turn on itself, or
drawn in any direction, the saw will naturally participate in the movement;

page_text: it is, in fact, the organ by which the saw is conducted in working. Under the
frame A is an oscillating lever F, one ende of which draws the saw frame
down, while its other end is raised by another lever G. This second lever is
moved either directly by a treadle as in an ordinary treadle saw, or by a
connecting rod as in a fly-wheel saw, or saw capable of working by steam,
horse-power, or any other force. The ascending movement is produced by a
spring K, K, placed on the frame A. Spiral springs rolled around the rod a,
and a double straight spring placed under the frame A, serve to absorb the
excess of momentum which the frame retains after each movement, and render
this force in the opposite direction, which prevents the waste of labour which
would otherwise result from the inertia of the saw frame.
The saw is
stretched very readily, and with a regular force, which is lessened according to
circumstances. For this purpose the frame C is formed of two round and
straight uprights, and two cross bars c and k; a third cross piece 9, so arranged
as to rise or descend between the uprights, is fixed to a round rod which slides
in the cross-piece k, and which carries the toothed wheel, a cam m on the
cross-piece g raises in turning the cross-piece k, and consequently the whole
frame. In order to lessen the tension or the length of the course the screw h
is turned, the cam acts only partially, and the tension is diminished. The
plank or other article it is wished to cut is held on the table by means of a
double-clawed press L. The part N of the table is sliding, and can be
approached to or withdrawn from the part M. In order to use the apparatus
as a fixed saw, which may be useful when the piece to be cut is very small, the
plate D is fixed by means of two supports provided with conical pins, which
are pushed into two catch pieces p and q placed on the posts, and into holes
worked in the table E, (one of these supports is represented in Fig. 4,) then
the table M is drawn towards the table N, and the saw is passed through a
hole n.
Thus the saw moving only in a vertical direction may be used in
the ordinary way by turning the piece to be cut about with the hands.
In the Drawing the apparatus is supposed to be moved directly by the
foot, but it may be worked by steam power or other motive force, or simply
with the foot by the interposition of a fly wheel mounted on the framework
itself. For this purpose the lever G, instead of being supported at its centre,
has its fulcrum at the end on the front leg of the framework, and is drawn at
the other end near its joint with the lever F by a connecting rod or cord
attached to an excentric or crank turning with an arbor placed on the part M
behind the press, on which arbor is fixed a pulley either grooved or flat, double
or single, according to the motive force employed. This pulley in turning
draws the lever G, which in its turns causes the lever F to oscillate. This

page_text: :
substitution of motive force and addition of a fly wheel being quite accessary
and independant of the principle of the Invention, cause little or no change
in the construction of the apparatus, except that the frame should be a foot
longer, and receive in addition an upright and a cross bar.
Having thus described the nature of the said Invention, and the manner in
which it is to be performed, what I claim is,-
Firstly, the double articulation of the frame allowing the saw blade to be
moved in any direction, while retaining its axe of rotation parallel to itself.
Secondly, the communication of the circular movement of the parts which
turn with one end of the saw to an arbor, and the communication between
this arbor and the parts turning with the other end of said saw.
Thirdly, a system of levers, one of which at least has its fulcrum moveable,
and participates in the movement of the jointed frames.
Fourthly, one or more springs intended to produce or aid the movement of
the saw in one direction, which springs are fixed to a moveable part of the
apparatus.
Fifthly, one or more springs intended to compensate for the inertia of the
saw frame after each course.
Sixthly, journals or guides which turn two or more rods, animated by an
up-and-down movement while keeping them parallel to each other.
: Seventhly, a catch clamp removable with the saw.
Eighthly, a cam and reversing screw for proucing an uniform, instan-
taneous, and easily regulated tension.
Ninthly, two parts of a table, which may be approached or withdrawn at
will for supporting the article to be cut.
And, tenthly, the mode of fixing the articulations in order that the saw may
move lengthwise only. The whole substantially as and for the purpose
above described.
In witness whereof, I, the said Henri Adrien Bonneville, have hereunto
set my hand and seal, this Second day of December, in the year of
our Lord One thousand eight hundred and sixty-three.
TT
DONNEVILLE