An Improved Guard for Circular Saws and other similar Machinery.
Year: 1899

page_text: Date of Application, 11th July; 1899
Complete Specification Left, 12th Sept., 1899-Accepted, 25th Nov., 1899
PROVISIONAL SPECIFICATION.
An Improved Guard for Circular Saws and other similar Machinery.
We, GEORGE ERNEST MENNELL, of Beverley Road, Norton, near Malton, in
the County of York, Timber Merchant, HENRY VINCENT MENNELL, of Number 7,
Claremont Terrace, Gillygate, in the City of York, Ironmongers' Assistant, and
THOMAS WALLS, of Number 14, Sheppard Street, Stoke-upon-Trent, in the County
of Stafford, Solicitor's Clerk, do hereby declare the nature of this invention
to be as follows:-
An inspection of the drawings hereto annexed will also further describe and
explain the said invention, and, unless otherwise stated, the letters and figures
used in this specification refer to the respective parts of the guard illustrated by
the drawing marked "Figure 1."
That part of the guard indicated by the letter A is a steel plate which passes
upward through the block R along the back of the saw and thus not only forms a
guard for the back of the saw but is also the support of the whole guard. Also
by being made concave in shape, and a stronger gauge at its base than at the
top, it renders the whole guard very rigid and prevents side waver.
It is also
made sufficiently thin so as to pass through the cut in the wood, and, by gradually
increasing in thickness from the front edge to the centre, it answers the purpose
of a riving knife. By again gradually diminishing in thickness from the centre
to the outside edge unnecessary friction is avoided.
Attached to the upper part of plate A by joint B is a short arm B which has
its underedge V shaped so as to slide in the groove C of the hood C.
The hood C is raised or lowered by altering the adjustment of the rod D by
means of the thumb screws E and F, which, in conjunction with the steel
suspension wire G, is a provision for expanding or contracting the upper portions
of the guard, and, in connection with the parts TV and P (Figure 1) and O
(Figure 3), hereinafter mentioned, is the means by which the guard is made
applicable to saws or cutters of different diameter or size.
The hood C has a V groove on its top or upper edge to receive B, and also a
long slot H in which the bolt of F and a small roller I travel.
The steel wire G passes through the connecting links J and forms the axle on
which the roller I revolves. Both ends of same are then bent in an upward
direction towards the respective ends of arm. K to which they are securely screwed
to a tight tension so as to hold the upper portions of the guard together and prevent
side waver.
The arm K passes through, and extends an equal distance on each side of,
plate A, and having a shoulder about midway butting up to plate A on one side,
is securely held in position by nut L.
One end of each of the two connecting links J are rivetted to the arm B by
rivet M, while at the other ends of the links and between same. is the small
revolving roller I above mentioned.
To the underside of the saw bench top is bolted two long parallel slides N N,
the end sections of which are also indicated by N N on Figure 4. The bottom

page_text: end of plate A passes through a slot in; and is affixed by a countersunk screw ◎
(Figure 3) and also by a countersunk screw P, to block R.
The upper part of block R is so made as to exactly fit and slide in the slides N N
and in the saw cavity of the bench top as shewn by Figure 4.
To the underside of block R are screwed two pieces of wood S S (Figures 1, 2
and 3) to stride rather more than the teeth of the saw so as to prevent the teeth
from coming in contact with the metal bench should the saw become heated or
buckled.
Passing through the block R at points T (Figures 3 and 4) is a long screw T,
which, being turned by the handle U, moves the block R backward or forward in
the slides N N and thus carries the whole guard backward or forward.
The guard is tilted backward or forward by means of the attachment V which
is adjusted by the thumb screw W and nut X. This attachment, in conjunction
with the long screw T, rod D, wire G, and countersunk screws P (Figure 1) and O
(Figure 3), is, as before stated, the provision for making the guard applicable
to saws or cutters of different diameter or size.
"
The drawing Figure 1" represents the guard fully expanded to suit a saw or
cutter of large diameter or size, whilst the drawing "Figure 2" represents the
guard contracted to suit a saw or cutter of small diameter or size and illustrates
how it always keeps parallel with the circumference of the saw or cutter. When
so contracted the groove C¹ of hood C passes down, and fits on, the inside edge of
plate A.
The drawing "Figure 3" shews the front end section of block R detached from
the saw bench, and further illustrates the manner in which the plate A passes
through, and is supported by, it.
The guard shewn on the drawings hereto annexed is suitable for saws from
thirty inches to forty-eight inches in diameter, (it is shewn over a thirty inch
saw in Figure 2 and over a forty eight inch saw in Figure 1) and one made on a
smaller scale would be suitable for saws from eighteen inches to thirty inches in
diameter.
An Improved Guard for Circular Saws and other similar Machinery.
We, GEORGE ERNEST MENNELL, of Beverley Road, Norton, near Malion, in
the County of York, Timber Merchant, HENRY VINCENT MENNELL, of Number 7,
Claremont Terrace, Gillygate, in the City of York, Ironmonger's Assistant, and
THOMAS WALLS, of Number 14, Sheppard Street, Stoke-upon-Trent, in the County
of Stafford, Solicitor's Clerk, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:―
This invention is applicable to circular saws and other similar revolving
cutters.
The objects of the said invention are to shield or cover the saw teeth or cutters
so that injuries to persons, falling upon or otherwise coming into contact with
saw teeth or cutters not shielded, are prevented, and also so as to prevent accidents
owing to pieces of wood being thrown forward from the back of the saw or cutter.
The manner in which the said invention is to be performed or carried into

page_text: practical effect will be readily understood on a perusal of the following description
and explanation thereof, and an inspection of the drawings annexed to or left
with our Provisional Specification. Unless otherwise stated, the letters and
figures hereinafter used refer to the respective parts of the guard illustrated by
Figure 1" of such drawings.
"6
That part of the guard indicated by the letter a is a steel plate which passes
upward through the block r along the back of the saw and thus not only forms
a guard for the back of the saw but is also the support of the whole guard. Also
by being made concave in shape, and a stronger gauge at its base than at the top,
it renders the whole guard very rigid and prevents side waver. It is also made
sufficiently thin so as to pass through the cut in the wood, and, by gradually
increasing in thickness from the front edge to the centre, it answers the purpose
of a riving knife. By again gradually diminishing in thickness from the centre to
the outside edge unnecessary friction is avoided:
Attached to the upper part of plate a by joint 61, is a short arm which has
its underedge shaped so as to slide in the groove c1 of the hood c.
The hood c is raised or lowered by altering the adjustment of the rod d by
means of the thumb screws e and f, which, in conjunction with the steel suspen-
sion wire g, is a provision for expanding or contracting the upper portions of the
guard and in connection with the parts t, r, and p (Figure 1) and o (Figure 3)
(hereinafter mentioned) is the means by which the guard is made applicable to
saws or cutters of different diameter or size.
The hood has a V groove on its top or upper edge to receive b and also has
a long slot in which the bolt of f and a small roller i travel:
The steel wire 7 passes through the connecting links and forms the axle on
which the roller revolves. Both ends of the same are then bent in an upward
direction towards the respective ends of arm to which they are securely
screwed to a tight tension so as to hold the upper portions of the guard together
and prevent side waver.
The arm k passes through, and extends an equal distance on each side of,
plate a and having a shoulder about midway butting up to plate a on one side
is securely held in position by the nut 7.
One end of each of the two connecting links are riveted to the arm 6 by
rivet m while at the other ends of the links and between same is the small
revolving roller above mentioned.
To the underside of the saw bench top is bolted two long parallel slides nn,
the end sections of which are also indicated by an on Figure 4. The bottom end of
plate a passes through a slot in, and is affixed by a countersunk screw o (Figure 3)
and also by a countersunk screw p, to block r.
The upper part of block r is so made as to exactly fit and slide in the slides n n
and in the saw cavity of the bench top as shewn by Figure 4.
To the underside of block 7 are screwed two pieces of wood s, s, (Figures 1, 2
and 3) to stride rather more than the teeth of the saw so as to prevent the teeth
from coming in contact with the metal bench should the saw become heated or
buckled.
Passing through block rat points 1; 1 (Figures 3 and 4) is a long screw t which
being turned by the handle moves the block backward or forward in the
slides a, and thus carries the whole guard backward or forward.
The guard is tilted backward or forward by means of the attachment which
is adjusted by the thumb screw w and nut.. This attachment in conjunction
with the long screw t, rod d, wire g, and countersunk screws (Figure 1) and o
(Figure 3) is, as before stated, the provision for making the guard applicable
to saws or cutters of different diameter or size.
The drawing "Figure 1" represents the guard fully expanded to suit a saw or
cutter of large diameter or size, whilst the drawing "Figure 2" represents the
guard contracted to suit a saw or cutter of small diameter or size and illustrates
how it always keeps parallel with the circumference of the saw or cutter. When

page_text: so contracted the groove 1 of hood c passes down and fits on the inside edge
of plate a.
"
.2%
The drawing "Figure 3" shews the front end section of block detached from
the saw bench, and further illustrates the manner in which the plate a passes
through, and is supported:by, it.
The guard shewn on the said drawings is suitable for saws from thirty inches
to forty eight.inches in diameter (it is shewn over a 30 inch saw in Figure 2 and
over a 48 inch saw in Figure 1), and one made on a smaller scale would be
suitable for saws from eighteen inches to thirty inches in diameter.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim is:―
The improved guard for circular saws and other similar machinery consisting,
substantially as hereinbefore described and illustrated by the said drawings, of
(1) a concave steel plate (after design a) to guard the back of the saw or cutters
and to support the whole guard; (2) an arm attached to the upper part thereof
(after design b) and (3) a hood (after design c) to guard other parts of the saw or
cutters; (4) adjusting rod, (5) short cross arm, and (6) suspension wire (after
designs d, k, and g); (7) a block (after design r), and in combination therewith,
two pieces of wood screwed thereto (after design s), two long parallel slides (after
design n) and a long screw and handle (after designs t, and u); and (8) an
attachment (after design ) for tilting the guard.
Dated this Ninth day of September One thousand eight hundred and'
ninatu
GEORGE ERNEST MENNELL,
HENRY VINCENT MENNELL,
THOMAS WALLS.