IMPROVEMENTS IN SAWS AND SAW MILLS
Year: 1852

page_text: LETTERS PATENT to Richard Archibald Brooman, of the firm of
Robertson, Brooman, and Co., of 166, Fleet Street, in the City
of London, Patent Agents, for the Invention of "IMPROVEMENTS
IN SAWS AND SAW MILLS"
A communication.
Sealed the 31st May 1853, and dated the 6th Deceinber 1852.
PROVISIONAL SPECIFICATION left by the said Richard Archibald
Brooman at the Office of the Commissioners of Patents, with
his Petition, on the 6th December 1852.
I, RICHARD ARCHIBALD BROOMAN, of the firm of Robertson, Broo-
man, and Company, of 166, Fleet Street, in the City of London,
Patent Agents, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN SAWS AND SAW MILLS" To be as follows:-
This Invention relates to certain improvements in saws and saw
mills.
The improvement in the construction of saws consist in so form-
ing the teeth that they shall act as chisels or planes, and cut away
the wood for forming the "kerf" or saw groove, instead of tearing
or rasping it, as in the old mode.
In the accompanying Drawings, Fig. 1, is a side view, and

page_text: Fig. 2, an edge view, of a fragment of a mill saw, which has the
improved form of teeth, and Fig. 3, is a side view of a circular
saw on the same principle. In the edge of the saw plate A, notches
B, B, are formed in any well-known or usual manner; C, C, are the
saw teeth between the notches formed in the saw plate. The outer
edges or faces a, of the whole series of teeth are in the same right
line in the reciprocating saw, and in the same circle in circular saws.
The cutting edges c, of the teeth are usually formed by upsetting
and inclining outwards the acute angles at the forward ends of their
outer edges or faces a, a. The teeth may be set in the usual
manner, for the purpose of cleaning themselves; but it is preferred
to allow the teeth to remain in the same plane with the saw plate,
and to spread out their cutting edges on each side a sufficient dis-
tance to form a suitable width of "kerf" for the saw plate to freely
play in.
After upsetting and throwing outward the cutting points of
the saw teeth, it is advisable to remove from the front of their
extremities, by means of a file or stone, a sufficient amount to bring
the cutting edges all on to the same right line in straight saws, and
to the same circular line in circular saws, and also a sufficient amount
to give firmness and strength to the outline of the cutting edges of
the teeth, as shewn at d, d. In the same manner is removed, from
the sides of the extremities of the cutting edges of the teeth, a suf-
ficient amount to bring both of said sides into planes parallel with
cach other, and also to give the requisite strength to the outline of
the cutting edges of the teeth. The points or cutting edges c, c,
of the teeth, are raised above the outer edges or faces a, a, of the
same, a distance equal to the thickness of the chip that each tooth
is intended to remove.
The fronts or cutting edges of the teeth may be set up by means
of a forked punch (D, Fig. 1), that is driven by a hammer, which
will give shape to both the inside and the outside of the points, and
at the same time raise them above the face a, of the tooth. The teeth,
if large and massive, asin mill saws, can have their points or cutting
edges set up with greater facility and regularity, by means of an

page_text: anvil F, of the form shewn in Figure 1, supported against the front
face a, of a tooth, and a punch E, held in the position shewn in the
Drawing, and struck with a hammer until the point is sufficiently
broad and acute, and conforms to the chamferred edge of the anvil.
It is obvious that the shape of the cutting edges of the teeth will
correspond with the above named punch, or of the punch and anvil,
and, consequently, they may receive the shape of chisels, gouges or
other shape best adapted to the particular kind of work to which
they are to be applied. Each of the saw teeth will cut off clearly
and smoothly a portion of the wood equal to the distance that its
cutting edge projects from the outer face a, of the same, in place of
the scraping action upon the wood exerted by the teeth of saws
constructed in the usual manner.
As relates to saw mills, the following is a full description thereof,
reference being had to the accompanying Drawings, making a part
of this Specification; Fig. 4, being a top view; Fig. 5, an end
view; Fig. 6, a longitudinal vertical section; and Fig. 7, a detached
portion, of the mills as arranged for re-sawing boards, &c.
This part of the Invention consists, in the first place, in the cin-
ployment of inclined ways for the saw gate, for the purpose of causing
the saw gate to strike forward as it descends, and to retreat back-
wards as it rises; by which arrangement the saw is enabled to be
placed in a straight position within its gate, and to be more uni-
formly strained, and with a greater degree of tension than usual,
which causes its teeth to cut with more energy and uniformity than
the teeth of saws when arranged in inclined positions within their
supporting frames or gates in the usual manner.
The second feature consists in making the saw gate ways adjust-
able, by which the action of the saw placed in the said gate can be
varied to suit the nature and the depth of the material to be operated
upon.
The third feature consists in the combination with each other of
all the ways of the saw gate, in such manner that they can be simul-
taneously and uniformly varied and adjusted in their positions,
whilst the saw gate is in motion.

page_text: The fourth feature consists in the arrangement of the feeding
apparatus in connection with the saw gate and the adjustable ways,
in such manner that the feed motion communicated thereby to the
material operated upon will invariably be in perfect harmony with
the cut of the saw; and consequently this said arrangement in con-
nection with the third feature enables the operation to instantane-
ously vary the amount of the action of the saw, for the purpose
of enabling him to case it when passing through knots, or to adapt
it to the nature of the materials.
The ways a, a, of saw gate B, are hinged to the fender posts A, A,
and they are all connected to each other by means of the screws b, b,
which may be either connected to the said ways, or form portions of
the same, and which pass through female screws in the centres of
the pulleys c, c, which pulleys work in slots in the fender posts,
or in other suitable guides, and are all connected to each other by
the endless band or chain d; it will therefore be perceived, that by
taking hold of the said endless band or chain and imparting motion
to the series of pulleys c, c, the ways a, a, of the saw gate can be
varied in their inclination to any desired extent, for regulating the
action of the saw and adapting it to the nature of the material ope-
rated upon.
Feeding motion is imparted to the carriage G, from the saw gate,
in the following manner, viz.: a transverse shaft E, rests in suitable
bearings under the carriage, and within a short distance of the
fender posts, which shaft is connected to the carriage by means of a
rope q, having a turn round a pulley on the said shaft, and with its
ends secured to the ends of the carriage, or, by means of a pinion on
the said shaft, gearing into a rack on the carriage in the usual manner;
a feeding wheel e, is secured to the shaft E, in the position shewn in
the Drawing; by the side of the said wheel e, a lever f, is also placed
upon the shaft E, and works freely thereupon. An arm g, projects
from the upper end of the lever f, over the top of the wheel e; o
gripper i, is jointed to the under side of the arm g, and is drawn
against the side of the wheel e, opposite to the lever f, by the spring
h, as shewn in the Drawings. When the lever f, is vibrated upor

page_text: the shaft E, the gripper i, will glide freely in one direction over the
surface of the wheel e; and when moved in an opposite direction, the
gripper will press so firmly against the side of the said wheel, as to
impart its own motion thereto. In place of the gripper i, a spring
pawl may be combined with the arm g, in such manner as to act in
conjunction with ratchet teeth secured to the side or to the peri-
phery of the wheel e. The advantage of the curvilinear movement
of the feeding gripper or hand over the ordinary tangential move-
ment of the feeding hand, consists in its being adapted to impart
a greater degree of motion to the feeding wheel, and also in its being
more certain and positive in its action. Motion is imparted to
the lever, from the saw gate, through the medium of the bar j,
the angular lever , and the short bar o, as shown in Figure 6.
The aforesaid bar j, and lever k, are connected to one of the saw
gate ways a, by incans of the bar 1, the lever m, and the bar n,
in the manner shewn in Figure 6; by which arrangement the
amount of motion imparted by the saw gate to the carriage G,
will be governed by, and exactly correspond with, the amount of
horizontal forward movement imparted by the ways a, a, to the
saw gate as it descends. To wit, the bent and slotted lever k, the
bar j, and the bar l, are connected to each other and to the lever k, by
means of a joint pin, which plays freely in a slot in the upright
portion of the said lever k, the lower end of the said bar a, being
jointed to the end of the long arm of the lever m, and the short arm of
the said lever being jointed to the lower end of one of the ways a, of
the saw gate by means of the bar n; it will be perceived that when the
inclination of the series of ways a, a, of the saw gate is varied, the
position of the pivot, will be moved in the slot in the short arm of
the lever , which will vary the amount of inotion imparted thereby,
through the bar j, the lever f, and the wheel e, to the carriage, and
cause it to exactly correspond with the degree of inclination given
to the ways of the saw gate, and the amount of forward horizontal
motion imparted by then to the saw gate during its descent.
For slitting or re-sawing plank, board, &c., a mill inay be con-
structed in the following exceedingly simple manner, viz.: Combine

page_text: with the fender posts of a suitable frame, the adjustable ways a, a,
and the saw gate B, substantially as represented in the Drawings
and herein-before set forth; then place upon suitable bearings a car-
riage H, Fig. 9, and connect it to the sides of the saw gate, by
means of the embracing ledges 1, 2, secured to the sides of the said
carriage. The saw plays in a slot in the forward end of the carriage,
and a pressing roller is combined with it in any well known and
usual manner, for the purpose of holding the board or plank when
it is operated upon by the saw. At the rear end of the said carriage
H, are arranged spring clamps t, t, in such manner that when the
carriage is inoved rearward, during the down stroke of the saw, the
said clamps will glide freely over the sides of the board, and when
the carriage is moved forward by the upward stroke of the saw, the
said clamps will grip the board and carry it forward to be again
acted upon by the saw. The jaws t, t, of the said spring clamp, arc
arranged and operated in the following manner, viz. the jaws are
connected to boxes u, u, by means of the forwardly inclining short
arins v, v; the boxes 2, 2, are secured between the ways s, s, and
slide freely therein. Set screws a, a, pass through the openings in
the connecting ends of the ways 8, 8, and pass into female screws
in the boxes u, u. Springs w, w, are connected to the tops of
the boxes u, u, and press rearward against the front sides of the
bars v, v, for the purpose of causing the jaws t, t, to bear lightly
against the board or plank, and prevent the said jaws from gliding
over the same when they are moved forward. It will therefore be
perceived, that when the carriage is moved rearward, the arms v, v,
having nearly free forward play, allow the jaws t, t, to glide over the
board or plank placed between the same; and when the said carriage
is moved forward, the light pressure of the jaws t, t, upon the board,
will cause them to incline the bars v, v, to the rear, and thereby
force the jaws upward and make them firmly grip and carry forward
whatever may be embraced between them.
The set screws x, x, and the cranks y, y, upon the same, serve to
vary the positions of the feeding clamps, and to adapt then to the
different thicknesses of stuff to be operated upon.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Richard Archibald Brooman in the Great Seal
Patent Office on the 6th June 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
RICHARD ARCHIBALD BROOMAN, of the firm of Robertson, Brooman,
& Co., of 166, Fleet Street, in the City of London, Patent Agents,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of December, in the
year of our Lord One thousand eight hundred and fifty two, in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Richard Archibald Brooman,
her special licence that I, the said Richard Archibald Brooman,
my executors, adininistrators, and assigns, or such others as I,
the said Richard Archibald Brooman, my executors, adininistra-
tors, 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 night 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
SAWS AND SAW MILLS," communicated to me by a foreigner residing
abroad, upon the condition (amongst others) that I, the said Richard
Archibald Brooman, by an instrument in writing under my hand
and seal, 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 Archibald Brooman, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, reference being had to the
Drawings hereunto annexed (that is to say):
This Invention relates to improvements in saws and saw mills.

page_text: The improvements in the construction of saws consist in so
forming the teeth that they shall act as chisels or planes, and cut
away the wood for forming the "kerf" or saw groove, instead of
tearing or rasping it, as in the methods hitherto practised.
Figure 1, of the accompanying Drawings, is a side view, and
Figure 2, an edge view, of a portion of a inill saw, the teeth of which
are formed according to the present Invention; and Fig. 3, is a side
view of a circular saw on the same principle. A, is the saw plate, in
the edge of which are formed notches B, B, in any well known
manner;
C, C, are the saw teeth between the notches formed in the
saw plate. The outer edges or faces a, of the whole series of teeth
are in the same right line in reciprocating saws, and in the same
circle in circular saws. The cutting edges c, of the teeth are
usually formed by upsetting and inclining outwards the acute
angles at the forward ends of their outer edges or faces a, a.
The teeth may be set in the usual manner, for the purpose of cleansing
themselves; but it is preferred to allow the teeth to remain in the
same plane with the saw plate, and to spread out their cutting edges
on each side a sufficient distance to form a suitable width of "kerf"
for the saw plate to play in freely.
After upsetting and throwing outward the cutting points of the
saw teeth, it is advisable to remove from the front of their ex-
tremities, by means of a file or stone, a sufficient quantity, so as to
bring the cutting edges all on to the same right line in straight
saws, and to the same circular line in circular saws; and also a
sufficient quantity to give firmness and strength to the outline of
the cutting edges of the teeth, as shewn at d, d. In the same
manner a sufficient quantity is removed from the sides of the ex-
tremities of the cutting edges of the teeth, so as to bring both of
the sides into planes parallel with each other, and also to give the
requisite strength to the outline of the cutting edges of the teeth.
The points or cutting edges c, c, of the teeth are raised above the
outer edges or faces a, a, of the same a distance equal to the thick-
ness of the chip that each tooth is intended to remove.
The points or cutting edges of the teeth may be set up by means

page_text: of a forked punch (D, Figure 1), driven by a hammer, which will
give shape to both the inside and outside of the points, and at the
same time raise them above the face a, of the tooth. The teeth, if
large and massive, as in mill saws, may have their points or cutting
edges set up with greater facility and regularity by means of an
anvil F, of the form shewn in Figure 1, supported against the front
face a, of a tooth and a punch E, which is held in the position
shewn in the Drawing, and struck with a hammer until the point is
sufficiently broad and acute, and conforms to the chamfered edge of
the anvil. It is obvious that the shape of the cutting edges of
the teeth will correspond with the above mentioned punch, or of
the punch and anvil, and consequently they may receive the shape,
of chisels, gouges or any other shape, best adapted to the particular
kind of work to which they are to be applied. Each of the saw
teeth will cut off clearly and smoothly a portion of the wood equal
to the distance that its cutting edge projects from the outer face a,
of the same, instead of exerting the scraping action upon the wood,
as is the case with saw teeth constructed in the usual manner.
The improvements in saw mills consist:-
Firstly, in the employment of inclined ways for the saw gate, for
the purpose of causing the saw gate to strike forward as it descends,
and to retreat backwards as it rises; by which arrangement the saw
is enabled to be placed in a straight position within its gate, and to be
more uniformly strained, and with a greater degree of tension than
usual, which causes its teeth to cut with more energy and uniformity
than the teeth of saws when arranged in inclined positions within
their supporting frames or gates in the usual manner.
Secondly, in making the saw gate ways adjustable, whereby the
action of the saw placed in the gate can be varied to suit the nature
and depth of the material to be operated upon.
Thirdly, in the combination with each other of all the ways of the
saw gate in such manner that they can be simultaneously and uni-
forinly varied, and adjusted in their positions whilst the saw gate is
in motion.
Fourthly, in the arrangement of the feeding apparatus in con-

page_text: nection with the saw gate and the adjustable ways, in such manner
that the feed motion communicated thereby to the material operated
upon will invariably be in perfect harmony with the cut of the saw;
and consequently this said arrangement in connection with the third
feature enables the operator to vary instantaneously the amount of
action of the saw, for the purpose of enabling him to case it
when passing through knots, or to adapt it to the nature of the
inaterials.
Figure 4, is a top view; Figure 5, an end view; Figure 6,
a longitudinal vertical section, of a saw mill constructed and ar-
ranged according to the present Invention; Figure 7, a detached
portion of the mills arranged for sawing logs; Figure 8, is a side
view, and Figure 9, a detached portion, of the mill as arranged for
re-sawing boards, &c.
The ways a, a, of saw gate B, are hinged to the fender posts
A, A; and they are all connected to each other by means of the
screws b, b, which may be either connected to the said ways or
form portions of the same, and which pass through female screws
in the centres of the pulleys c, c, which pulleys work in slots in
the fender posts, or in other suitable guides, and are all connected
to each other by an endless band or chain d. It will, therefore, be
perceived, that by taking hold of the said endless band or chain, and
imparting motion to the series of pulleys c, c, the ways a, a, of the
saw gate can be varied in their inclination to any desired extent, for
regulating the action of the saw, and adapting it to the nature of the
material operated upon.
Feeding motion is imparted to the carriage G, from the saw gate,
in the following manner, videlicet: A transverse shaft E, rests in
suitable bearings under the carriage, and within a short distance
of the fender posts, which shaft is connected to the carriage by
means of a rope q, having a turn around a pulley on the said shaft,
and with its ends secured to the ends of the carriage, or by means
of a pinion on the said shaft gearing into a rack on the carriage
in the usual manner. A feeding wheel e, is secured to the
shaft E, in the position shewn in the Drawing by the side of the a

page_text: said wheel e; a lever f, is also placed upon the shaft E, and works
freely thereupon. An arm 9, projects from the upper end of the
leverf, over the top of the wheel e; a gripper i, is jointed to the under
side of the arm g, and is drawn against the side of the wheel e, op-
posite to the lever f, by the spring h, as shewn in the Drawings.
When the lever f, is vibrated upon the shaft E, the gripper i, will
glide freely in one direction over the surface of the wheel e, and when
moved in an opposite direction, the gripper will press so firmly
against the side of the said wheel as to impart its own motion thereto.
In place of the gripper i, a spring pawl may be combined with
the arin g, in such manner as to act in conjunction with ratchet
teeth fixed to the side or to the periphery of the wheel e. The ad-
vantage of the curvilinear movement of the feeding gripper or hand
over the ordinary tangential movement of the feeding hand consists
in its being adapted to impart a greater degree of motion to the
feeding wheel, and also in its being more certain and positive in
its action. Motion is imparted to the lever f, from the saw gate
through the medium of the bar j, the angular lever k, and the short bar
O, as shewn in Figure 6. The aforesaid bar j, and lever k, are con
nected to one of the saw gate ways a, by means of the bar I, the
lever m, and the bar n, in the manner shewn in Figure 6; which
arrangement the amount of motion imparted by the saw gate to the
carriage G, will be regulated by, and exactly correspond with, the
amount of horizontal forward movement imparted by the ways a, a,
to the saw gate, as it descends; that is to say, the bent and slotted
lever k, the bar j, and the bar l, are connected to cach other, and to
the lever k, by means of a joint pin, which plays freely in a slot in
the upright portion of the lever k; the lower end of the bar a, being
jointed to the end of the long arm of the lever m, and the short arm
of the said lever being jointed to the lower end of one of the ways a,
of the saw gate, by means of the bar n, it will be perceived that when
the inclination of the series of ways a, a, of the saw gate is varied
the position of the pivot z, will be moved in the slot in the short arm
of the lever k, which will vary the amount of motion imparted
thereby through the bar j, the lever f, and the wheel e, to the carriage,

page_text: and cause it to exactly correspond with the degree of inclination
given to the ways of the saw gate, and the amount of forward
horizontal motion imparted by them to the saw gate during its
descent.
Forslitting or re-sawing planks, board, &c., a mill may be constructed
in the following exceedingly simple manner, vizt.: The fender posts
of a suitable frame is combined with the adjustable ways a, a, and
the saw gate B, substantially as represented in the Drawings, and
herein-before described; then a carriage H, Figure 9, is placed upon
suitable bearings, and connected to the sides of the saw gate by means
of the embracing ledges », r, secured to the sides of the said carriage.
The saw plays in a slot in the forward end of the carriage, and a
pressing roller is combined with it, in any well known and usual
manner, for the purpose of holding the board or plank when it is ope-
rated upon by the saw. At the rear end of the said carriage H, are
arranged spring clamps t, t, in such manner, that when the carriage
is moved rearward during the down stroke of the saw, the said clamps
will glide freely over the sides of the board, and when the carriage
is noved forward, by the upward stroke of the saw, the said clamps
will grip the board, and carry it forward to be again acted upon by
the saw.
The jaws t, t, of the said spring clamp are arranged and
actuated in the following manner, vizt.: The jaws are connected to
boxes u, u, by means of the forwardly inclining short arms v, v; the
boxes u, u, are secured between the ways and s, s, slide freely therein;
set screws x, x, pass through the openings in the connecting ends of
the ways s, s, and pass into female screws in the boxes u, u; springs
w, w, are connected to the tops of the boxes u, u,: and press rearward
against the front sides of the bars v, v, for the purpose of causing the
jaws t, t, to bear lightly againt the board or plank, and prevent the
jaws from gliding over the same when they are moved forward. It
will, therefore, be perceived that, when the carriage is moved rear-
ward, the arms v, v, having nearly free forward play, allow the jaws
t, t, to glide over the board or plank placed between the saine, and
when the carriage is moved forward, the light pressure of the jaws
t, t, upon the board will cause them to incline the bars v, v, to the

page_text: rear, and thereby force the jaws upward, and make them firınly grip
and carry forward whatever may be embraced between them. The
set screws r,, and the cranks y, y, upon the saine serve to vary
the
positions of the feeding clamps, and to adapt them to the different
thicknesses of material to be operated upon.
And having now described the nature of the said Invention, and
the manner in which the same is to be performed, I declare that I
claim, as of the said Invention,-
Firstly, in respect of the improvements in saws, forming the
cutting edges of the teeth inclining outward from plane or curved
surfaces to a distance equal to the thickness of the chip that each tooth
is intended to remove from the wood, and also preventing the said
tooth from taking a deeper hold of the wood than the said regulated
depth as herein-before described.
Second, I claim, in the improvements in saw mills, the adjust-
able ways of the saw gate, and the manner of connecting them
together, so that they shall be capable of adjustment by varying
the angle of the ways as herein-before described; also the feeding
arrangement as combined, and operating with the saw gate and
adjustable ways, so that the feed may be regulated by the regulation
of the saw and ways so fitted as to cut or saw any particular kind
of materials as herein-before described.
In witness whereof, I, the said Richard Archibald Brooman,
have hereunto set my hand and seal, this Sixth day of June,
One thousand eight hundred and fifty-three.
K..
R. A. BROOMAN. (L.S.)