IMPROVEMENTS IN BENCH SAWING MACHINERY WORKED BY HAND OR POWER
Year: 1876

page_text: LETTERS PATENT to William Blackett Haigh, of Oldham, in the County of
Lancaster, for the Invention of "IMPROVEMENTS IN BENCH SAWING MACHINERY
WORKED BY HAND OR POWER."
Sealed the 5th January 1877, and dated the 8th July 1876.
PROVISIONAL SPECIFICATION left by the said William Blackett Haigh at
the Office of the Commissioners of Patents on the 8th July 1876.
WILLIAM BLACKETT HAIGH, of Oldham, in the County of Lancaster.
MENTS IN BENCH SAWING MACHINERY WORKED BY HAND OR POWER."
"IMPROVE-
One part of this Invention consists in adapting the framework and various parts
of the circular saw bench with certain additions and alterations for enabling a
straight fret saw to be used as well as a circular one. For this purpose I employ a
slide working in guides, and connect to it two arms, to which the saw is adjusted
and held by screws and nuts in the ordinary manner, and for giving up-and-down
motion to the slide arms and saw I employ a crank connected by a rod to a pin on
the slide, and give motion to the crank by means of a pulley driven by a strap and
a pulley on the circular saw spindle.
Another improvement relates to band sawing machines, and consists in placing
one of the pulleys carrying the band saw on a stud at one end of a double lever,
there being at the other end a spiral spring; the double lever working on a fulcrum
or shaft working in bearings placed in a slide fitted to guides, and having below it
the ordinary tightening or regulating screw and nut, and thus, by placing the
pulley on the arm of a lever, the tension can be so adjusted that much less power
is required to work the saw.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said William Blackett Haigh in the Great Seal Patent Office on the 8th
January 1877.
(6
WILLIAM BLACKETT HAIGH, of Oldham, in the County of Lancaster. IMPROVE-
MENTS IN BENCH SAWING MACHINERY WORKED BY HAND OR POWER."
The first part of this Invention consists in adapting the framework and various
parts of the circular saw bench with certain additions and alterations for enabling a
straight fret set to be used as well as a circular one. For this purpose I employ a
slide working in guides, and connect to it two arms, to which the saw is adjusted
and held by screws and nuts in the ordinary manner, and for giving up-and-down
motion to the slide arms and saw I employ a crank connected by a rod to a pin on
the slide, and give motion to the crank by means of a pulley driven by a strap and
a pulley on the circular saw spindle.
The second part of my Invention relates to bench sawing machines, and consists
in placing one of the pulleys carrying the band saw on a stud at one end of a double
lever, there being at the other end a spiral spring, the double lever working on a
fulcrum or shaft working in bearings placed in a slide fitted to guides and having
below it the ordinary tightening or regulating screw and nut, and thus by placing
the pulley on the arm of a lever the tension can be so adjusted that much less power
is required to work the saw.
This Invention will be clearly understood by reference to the accompanying
Sheet of Drawings with the figures and letters of reference thercon, in which Fig. 1
is a side elevation of the first part of my Invention, shewing my method of utilizing
a circular saw bench for working a fret saw. Fig. 2 is a side elevation of the
second part of my improvements relating to band sawing machines.
.
In Fig. 1a represents the bench or framework of the machine, and 6 the driving
shaft. The slide & works in the guides e, and has connected to it the two arms f, g,
"to which the saw his adjusted and held by the screws and nuts i,j; and for giving
the up-and-down motion to the slide d, arms f, g, and saw h, I employ the crank
connected by the rod 7 and pin n on the slide, motion being given to the crank by
the pulley m driven by tlie strap n and driving wheel o on the circular saw spindle.
For balancing and assisting the slide in its backward motion I use a spring p fixed
to the bracket a¹, its other end working under an anti-friction pulley q on the
slide d.
In Fig. 2 a represents the bench or framework and b the driving shaft of the
machine; b, the regulating or tension pulley carrying the band saw b² fixed on the
stud c¹ at one end of the double lever d, there being at the other end the spiral
spring e¹. The double lever d¹ works on the fulcrum or stud f¹ fixed to the slide g¹
working in the guides and having below it the ordinary tightening or regulating
screw and nut i¹; and when the machine is working the effect of this arrangement of
double lever and spring is to allow a small amount of play to the saw, so that if it
should come in contact witli a knot or other non-yielding substance it will give
way to it, and thereby prevent breakages. The slide y¹ is only moved when a new
saw is put in or one shortened, and the arm carrying the socket for the spring e¹
and the double lever being both attached. to it, it follows that when the slide is
moved either upwards or downwards to regulate the tension or length of the saw
that the arm j and double lever d' move with it, thereby always keeping their
relative positions and so avoiding the necessity of changing or adjusting one to the
other.
1
Having now described the nature and particulars of my said Invention, I desire
it to be understood that I claim-
First. The general arrangement of the machine, as shewn and described, for
enabling a straight fret saw to be used in combination with a circular one on the
ordinary circular saw bench.

page_text: And, Secondly. In band sawing machines the placing the regulating or tension
pulley carrying the band saw on a stud at one end of a double lever, at the other end
of which is a spiral spring for the purpose of regulating the tension of the saw when
working, and the mode or method of fastening the double lever d', bracket j¹, and,
slide q together, as and for the purposes herein-before described and illustrated on
the accompanying Sheet of Drawings.
In witness whereof, I, the said William Blackett Haigh, have hereunto set my
hand and seal, this Fifth day of January, in the year of our Lord One
thousand eight hundred and seventy-seven.
Signed, sealed, and delivered by the within-
named William Blackett. Haigh in the
presence of,
G. SEPTIMUS HUGHES,
Patent Agent,
Manchester.
W. B. HAIGH. (L.S.)