An Improved Mitre Cutter or Trimmer.
Year: 1892

page_text: Date of Application, 29th Feb., 1892
Complete Specification Left, 25th Nov., 1892-Accepted, 11th Feb., 1893
PROVISIONAL SPECIFICATION.
An Improved Mitre Cutter or Trimmer.
I, WILLIAM Ross Fox, of Grand Rapids, Kent County, State of Michigan,
United States of America, Manufacturer, do hereby declare the nature of this
invention to be as follows:-
My invention is a wood working machine for cutting mitres and includes a
sliding knife and an adjustable gauge having a shearing edge to act in conjunction
with the cutting edge of the knife which shearing edge is maintained at the line of
cut in all positions of the gauge.
In machines of this class it is highly important that the strain resulting from the
pressure of the knife be sustained by the standards or posts of the machine in order
to relieve the adjustable gauge and I have therefore made my invention with this
essential feature in view, the gauge in all its positions bearing vertically along the
standard or post and thus accurately and securely held against lateral strain from
the knife.
The invention includes among its features of novelty, the means for controlling
the movements of the gauge in its adjustments, so that the shearing edge will
always be at the line of cut. It includes further a new form of knife and the
manner in which it is supported on the knife carriage and guided in the frame work
to prevent springing under the strain of the work; a balance weight for the
operating lever so that the knife will remain in any position in which it is left;
protecting wings extending out from the machine frame acting to shield the knife
edge when the knife is left in its extreme outward position and thus prevent
accidents to the workman; and other features hereinafter pointed out.
The machine consists of a frame or bed, upright posts or standards at the ends of
the knife way in which the knife carriage slides, and the adjustable gauges. The
gauges are arranged to bear laterally along the upright posts or standards, and in
adjusting the gauge to its various angular positions, one vertical edge of the gauge
bears upon and moves along the face of one of the posts and the adjacent vertical
edge forms the shearing edge and at all times the strain resulting from the pressure
of the knife against the shearing edge is sustained by the post throughout the
vertical extent of the gauge.
The rear of the gauge has a jam nut, which travels in a slot, in the machine bed,
and by which the gauge when adjusted to the proper position may be fixed.
This slot and nut do not determine the position of the shearing edge of the gauge
but serve only to hold the rear end of the gauge.
In order to control or guide the movement of the gauge so that the shearing
edge will always be at the path of the knife, a guide way is formed between the
horizontal meeting faces of the gauge and the machine frame, and preferably in the
bed directly under the forward end of the gauge.
This guideway is preferably a groove or slot and into it projects a pin, upon
which the gauge pivots when being adjusted. This pin is provided with a sliding
block accurately fitted in the slot. The centre of the pivot is equally distant from
the sides of the gauge, and the slot is formed on an incline, the central line thereof
coinciding with the mitre line drawn from the corner of the gauge, which bears
against the post, through the pin and equally dividing the right angle between the
bearing face of the post and the line of cut.
From this construction it will be clear that as the gauge is adjusted or turned
on its pivot one of its vertical edges bears upon and moves along the face of
the post, and the sliding block with the gauge pivot travels in the inclined slot
and this controls the movement in such manner as to maintain the adjacent

page_text: vertical edge which forms the shearing edge always on the line, along which the
knife moves and this is true even if the gauge be adjusted to the full 90° from
its normal position. I do not limit myself to the precise position of the guiding
way, nor to the precise form of said guideway, nor do I wish to be understood as
being compelled to use the sliding block, though this is desirable on account of
reducing the liability of lost.motion in the gauge.
In some cases I use a link combined with the gauge and guiding means already
described. The link is pivoted by an adjustable bracket, secured to the upright
post by a screw passing through a slot, and it is pivoted to the gauge by the pin
of the sliding block. The link is above the plane of the bed, and the gauge is
formed with a slot or recess, to receive the end thereof. This link also serves to
control the movement of the gauge and together with the inclined guideway
insures a perfect action. It is desirable that the pivot of the link whereby it is
attached to the bracket shall be on a line drawn from the shearing edge of the
gauge through the gange pivot. The adjustment of the bracket attached to the
post and its pivot makes it convenient to get the shearing edge at a proper distance
from the knife. The movement of the free end of the link is so slight that in
practice it does not move materially from a straight line, and therefore moves with
the pivot in the slot. It is often found desirable or necessary to make a very
slight bevel cut from the end of a piece of wood. I have therefore arranged the
cross bar which forms the upper knife way so that its rear face will be practically
even with or a little forward of the face of the knife and the cutting edge. This
will allow the piece of wood when set upright to be at the line of the cut, and by
tilting it very slightly its lower end will cross the line of cut, and a bevel of slight
angle may thus be formed. In other words the cross bar is free from projections
which would olistruct the space in rear of the knife and this is left entirely clear
above the knife: for allowing the material to be placed close to the cutting edge.
By having the rear face of the frame slightly forward of the knife edge the whole
of said edge is brought into the action of cutting.
In order to prevent the upper edge of the knife from springing out I form a
groove in the top bar and rabbet the upper end of the knife, thereby fitting it,
to the groove in which it travels and it is held against lateral deflection; or
the flange of the top bar may be bevelled, while the upper edge of the knife is
formed to correspond thereto.
I provide projecting wings extending from the main frame in a plane parallel.
with and close to the face of the knife and these wings extend a little. beyond
the extreme point of the knife's movement in either direction. These, wings act.
as shields and prevent the knife edge from being exposed when in either extreme
position, and thus there is no liability of the operator being cut accidentally by
reason of the edge of the knife projecting beyond the frame. The wings are
triangular in shape, their outer edges being inclined to conform to the incline of
the cutting edge. They are provided with ribs about their edges on the face
adjacent to the knife, and these aid in shielding the knife.
The movement of the gauge so as to maintain its shearing edge at the line of cut
may also be controlled in the following way;
The upright post has a curved face which is struck from the shearing edge of
the gauge as a centre. The gauge has an enlargement the face of which is, curved
to correspond with the curved face of the post, being struck from the. shearing
edge as a centre. The free end of the gauge has the jam nut and slot connection
before described and when the gauge is turned into its various angular positions
the curved bearing faces will keep the shearing edge at the line of cut.
The gauge may have in addition a curved bearing below in the form of a pintle
or an upper arm bearing against a stud on the frame. The curve of the end
of the arin is struck from the shearing edge as a centre. The gauge will thus.
be held against displacement either forward or backward in all its angular
positions and the shearing edge prevented from moving across, the line of cut or
receding from it.

page_text: The cutting knife is fixed to a carriage which slides in ways formed in a top
bar, which spans the upright posts, aud in the frame of the machine. The knife
carriage is provided with a rack in which a segment of a pinion, carried from the
base of the machine, gears; the segment is operated by a lever handle attached
thereto and in order to balance the weight of the lever so that the carriage and
knife will remain in any position in which it is left, I provide a weight connected
to the lever by a bevelled tongue and groove, this weight is heavy enough to
prevent the weight of the lever from moving the carriage either one way or the
other when the said lever is in an inclined position.
The carriage after continued use is easy to move even by the mere weight of the
lever and the weight is provided to prevent this. The weight may be heavy enough
to return the lever with the carriage to their central position.
In order to prevent springing of the knife under the strain of the work I
furnish a support for the upper portion which is the first part of the cutting edge
to enter the material to be cut, the edge inclining towards the centre of the
machine. This support is provided by forming a lug or extension on the knife
extending above the line of the cut, the depth of the frame work being preferably
increased to accommodate this lug or extension. The carriage is also formed
deeper and is provided with an extension reaching over the knife extension to
afford a lateral bearing for the same. The knife extension is secured to the
carriage by screws which make the fastening secure and maintain the cutting edge
and particularly the upper portion thereof against springing. The knife
throughout its body portion is held by screws to the carriage in the usual
manner.
Instead of the several means before described for controlling the movement
of the gauge to keep its shearing edge at the line of cut as it moves towards and
from the bearing post I may specially form the curved slot by which the rear of
is guided to accomplish the same purpose.
the gauge
The contour of the slot may be set out geometrically and the slot then formed,
or the slot can be milled by a inilling tool directly as follows;-
The bearing face of the post is finished and a bearing on the front is formed
temporarily by means of a bar or plate of steel fixed between the carriage of the
knife and the gauge of the same thickness as the knife, so that the face of it will
be in the same plane in which the shearing edge of the gauge is to be held. The
milling tool is carried in an arm the front end of which is of the same dimensions
in horizontal plane as the front end of the gauge. It corresponds in shape to the
gauge on the sides and ends. The milling tool is rotated by any suitable mechanism
and the bar is turned the outer end moving in a curved direction and the inner end
kept firmly against the post and the bar while the milling tool is operated. This
cuts the slot directly and of the contour required.
Since this slot and the connections therein serve not only to hold the gauge in
position when it has been set in proper position, but also to guide it to the proper
position and to maintain the shearing corner always in the plane of the cut or in a
plane parallel therewith, it is essential that the rear end of the gauge be held snugly
in the curved slot and to this end a plug is provided, fitted to move snugly in the
slot, having a hole through which a clamp screw is inserted, this screw having a
nut on its lower end to hold the parts securely in place. Instead of the plug being
made separate, it may of course be made with the gauge, though I prefer the
former construction as it is much less expensive, but I do not limit myself as to the
particular mechanism for holding the gauge snugly in the slot.
Dated this 27th day of February 1892.
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool, Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
An Improved Mitre Cutter or Trimmer.
I, WILLIAM Ross Fox, of Grand Rapids, Kent County, State of Michigan,
United States of America, Manufacturer, 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 :-
My invention is a wood working machine for cutting mitres and includes a
sliding knife and an adjustable gauge against which the material to be cut bears,
the said gauge having a shearing edge to act in conjunction with the cutting edge
of the knife which shearing edge is maintained at the line of cut in all positions of
the gauge.
In machines of this class it is highly important that the strain resulting from
the pressure of the knife be sustained by the standards or posts of the machine in
order to relieve the adjustable gauge and I have therefore made my invention
with this essential feature in view, the gauge in all its positions bearing vertically
along the standards or posts and thus accurately and securely held against lateral
strain from the knife.
The invention includes among it's features of novelty, the means for controlling
the movements of the gauge in its adjustments, so that the shearing edge will be
always at the line of cut. It includes further a new form of knife and the manner
in which it is supported on the knife carriage and guided in the frame work to
prevent springing under the strain of the work; a balance weight for the operating
lever so that the knife will remain in any position in which it is left; protecting
wings extending out from the machine frame acting to shield the knife edge when
the knife is left in its extreme outward position and, thus prevent accidents to the
workman, and other features hereinafter pointed out.
In the drawings
Figure 1 is a plan view of the machine.
Figure 2 is a detail of an additional means for controlling the movement of the
shearing edge as the gauge is adjusted.
Figures 3 and 4 are detail views of modified means for this purpose.
Figure 5 is a vertical section on line 4-4 of Figure 1, the dotted lines showing
the modified controlling means of Figures 3 and 4.
Figures 6 and 7 represent two different ways of guiding the knife in the frame.
Figure 8 is a rear view of the machine showing the improved form of knife and
carriage.
Figure 9 is a perspective view of the gauge shown in Figures 3 and 4 and dotted
lines of Figure 5.
Figures 10 and 11 are views of the two different forms of knife shown applied to
the right and left of the carriage of Fig. 8.
L
Figure 12 illustrates the manner of laying off the curved controlling slot for the
gauge.
Fi
Figure 13 shows one way in which said slot may be formed.
In these drawings 1, is the machine frame or bed, 2, the posts or standards at
the ends of the knife way 3, and 4 are the gauges. These gauges are arranged to
bear laterally along the posts 2, and in adjusting the gauge to its various angular
positions, the edge 1x bears upon and moves along the face of the post, and at all
times the strain resulting from the pressure of the knife is sustained by the post
throughout the vertical extent of the gauge.
Referring to Figures 1 and 5, the rear of the gauge has a jam nut 5, which
travels in a slot 6, in the machine bed, and by which the gauge when adjusted to
the proper position may be fixed.
This slot and nut do not determine the position of the shearing edge 4*,
only to hold the rear end of the gauge,
but serve

page_text: In order to control or guide the movement of the gauge so that the shearing
edge 4*, will always be at the path of the knife, a guide way 7 is formed between
the horizontal meeting faces of the gauge and the machine frame, and preferably in
the bed directly under the forward end of the gauge.
This guideway is preferably a groove or slot and into it projects a pin 5*, upon
which the gauge pivots when being adjusted. This pin is provided with a sliding
block 9 accurately fitted in the slot. The centre of the pivot is equally distant
from the sides of the gauge, and the front 6*, and the slot is formed on an incline,
the central line thereof as at L, coinciding with the mitre line drawn from the
corner of the gauge through the pin and equally dividing the right angle between
the bearing face of the post and the line of cut.
From this construction it will be clear that as the gauge is adjusted or turned on
its pivot the edge 1* bears upon and moves along the face of the post, as shown,
and the sliding block with the gauge pivot travels in the inclined slot to the
position indicated on the right of Figure 1, and this controls the movement in such
manner as to maintain the shearing edge 4*, always on the line M, M, along which
the knife moves and this is true even if the gauge be adjusted to the full 90° from
its normal position shown in full lines. I do not limit myself to the precise
position of the guiding way shown, nor to the precise form of said guideway, nor
do I wish to be understood as being compelled to use the sliding block shown,
though this is desirable on account of reducing the liability of lost motion in the
gauge.
In Figure 21 show the link 10 combined with the gauge and guiding means
already described. The link is pivoted at 12, to an adjustable bracket 13, secured
to the post 2, by a screw passing through a slot, and it is pivoted to the gauge by
the pin of the sliding block. The link is above the plane of the bed, and the
gauge is formed with a slot or recess a, to receive the end thereof. This link also
serves to control the movement of the gauge and together with the inclined guide-
way insures a perfect action. It is desirable that the pivot 12, of the link shall be
on a line drawn from the corner of the gauge through the gauge pivot. The
adjustment of the bracket 13 with the pivot 12, makes it convenient to get the
shearing edge at a proper distance from the knife. The movement of the free end
of the link is so slight that in practice it does not move materially from a straight
line, and therefore moves with the pivot in the slot. It is often found desirable or
necessary to make a very slight bevel cut from the end of a piece of wood. I have
therefore arranged the cross bar 14 which forms the upper knife way so that its
rear face 15 will be practically even with or a little forward of the face of the
knife and the cutting edge. This will allow the piece of wood when set upright to
be at the line of the cut, and by tilting it very slightly its lower end will cross the
line of cut, and a bevel of slight angle may thus be formed. In other words the
cross bar is free from projections which would obstruct the space in rear of the
knife and this is left entirely clear above the knife for allowing the material to be
placed close to the cutting edge.
By having the rear face of the frame slightly forward of the knife edge the
whole of said edge is brought into the action of cutting.
In order to prevent the upper edge of the knife from springing out I have
formed a groove in the top bar and rabbet the upper end of the knife thereby
fitting it to the groove in which it travels and it is held against lateral deflection.
This is shown in Figure 6 in which the flange 15 bears against the shoulder 16
formed on the knife.
In Figure 7 the flange 15 is bevelled, while the upper edge of the knife is
formed to correspond thereto.
In Figure 1, projecting wings 17 are shown as extending from the main frame in
a plane parallel with and close to the face of the knife and these wings extend a
little beyond the extreme point of the knife's movement in either direction. These
wings act as shields and prevent the knife edge from being exposed when in either

page_text: extreme position, and thus there is no liability of the operator being cut accidentally
by reason of the edge of the knife projecting beyond the frame. The wings are
triangular in shape, tlieir outer edges being inclined to conform to the incline of
the cutting edge. They are provided with ribs about their edges on the face
adjacent to the knife, and these aid in shielding the knife.
In Figures 3 and 4 are shown another means for controlling the movement of
the gauge so as to maintain its shearing edge at the line of cut.
The post 2 has a curved face 19 which is struck from the point 4* as a centre.
The gauge has an enlargement 20 the face of which is curved to correspond with
the curved face of the post, being struck from the shearing edge 4* as a centre.
The free end of the gauge has the jam nut and slot connection before described
and when the gauge is turned into its various angular positions the curved bearing
faces will keep the shearing edge 4* at the line of cut.
The gauge may have in addition a curved bearing below in the form of a pintle
or an upper arm 21 bearing against a stud 22 on the frame, Figure 4 and dotted
lines Figures 3 and 5. The curve of the end of the arm 21 is struck from the
shearing edge +* as a centre. The gauge will thus be held against displacement
either forward or backward in all its angular positions and the shearing edge
prevented from moving across the line of cut or receding from it."
In order to balance the weight of the lever so that the carriage and knife will
remain in any position in which it is left, I provide a weight 23, Figures 5 and 8,
on the lever 25 which lever moves the carriage 26 through the segment 27 pivoted
to the machine frame and the rack 28 on the carriage. The weight is connected
to the lever by a bevelled tongue and groove and is heavy enough to prevent the
weight of the lever from moving the carriage either one way or the other, when
said lever is in inclined position.
The carriage after continued use is easy to move even by the mere weight of the
lever and the weight is provided to prevent this. The weight may be heavy enough
to return the lever with the carriage to their central position.
In order to prevent springing of the knife under the strain of the work I furnish
a support for the upper portion close to the point 30, Figure 8, which is the first
part of the cutting edge to enter the material to be cut, the edge 16x inclining
away from this point towards the centre of the machine. This support is provided
by forming a lug or extension 31 on the knife extending above the point 30 and
the upper line of the cut the depth of the frame work from - being
preferably increased to accommodate this lug or extension. The carriage is also
formed deeper and is provided with an extension 32 reaching over the plane of
the point 30 and along side the knife extension to afford a lateral bearing for the
same. The knife extension is secured to the carriage above and adjacent to the
point 30 by a screw 18* and a second screw 19* is also used to make the fastening
secure and maintain the cutting edge and particularly the point 30 against springing.
The knife throughout its body portion is held by screws to the carriage in the
usual manner.
In Figure 10 the knife on the right of Figure 8 is shown separately while in
Figure 11 and on the left of Figure 8 a modification is shown in which the lug or
extension is of the full thickness above the point 30 the bevel in this case extending
only to the upper line of the cut.
Instead of the several means before described for controlling the movement of
the gauge to keep its shearing edge at the line of cut as it moves towards and from
the bearing post I may specially form the curved slot 6 to accomplish the same
purpose, reference being had to Figures 12 and 13 which show the form of said
slot, the manner in which it may be laid off and one way in which it may be
formed.
The line 4*, y, is supposed to indicate the position of the bearing face of the
gauge when it is at right angles to the line of cut. The curved slot is shown at S;
T indicates the block fitted to move snugly in it bearing against the walls of the

page_text: slot. Let the line 4x, y, be supposed to be six inches, it will indicate the distance
between the outer end of the curve and the point 4* where the shearing edge
coincides with the line of cut on which that point is to be held and along which it
moves as the gauge is adjusted. I then sub-divide the line 4* to 1* into an equal
number of parts, for example ten, the sub-divisions being indicated by marks a, b,
c, d, &c. Then I turn the gauge keeping it in contact with the post on the left
hand side until the corner 4* coincides with the point a, the first point of the sub-
division. Then a point a laid off on the line of the bearing face of the gange six
inches from the point a, will indicate therefore the margin of the curve S.
In the
same manner I shift the corner 4* to the next point B, and in the same manner lay
off the line,, six inches in length. In a similar manner I turn the gauge
keeping its left hand side bearing against the post until I have indicated a curve
long enough to get the required sweep to the gauge and a curve drawn through the
line y, a', ', &c. to a will indicate the form of the curve to be made.
The curve
if continued to the line 1*, z would be at the point where it strikes that line six
inches distance from the point 1*. Practically it is not necessary to extend the
curve to that point but the slot in practice is laid off on a curve the outer end of
which is the same distance from a point where a line on the bearing face of the
gauge at right angles to the line of cut, crosses said line of cut as the point where
the inner end of the curve crosses the line of cut, is from the point where the plane
of the bearing face of the post crosses the line of the cut and the intermediate parts
of the curve, taken from the outer to the inner end, are successively equidistant
from the points taken in the same order and degree of succession from the point
where the line of cut crosses the plane of the bearing face of the post.
In the practical manufacture of my improved gauge I can mill the curve in the
bed by means of the apparatus illustrated in Figure 13. The bearing face of the
post 2 is finished and a bearing on the front is formed temporarily by means of a
bar or plate of steel E fixed between the carriage of the knife of the same thickness
as the knife, so that the face of it will be in the same plane in which the shearing
edge of the gauge is to be held. The tool consists of a milling tool D carried in
an arm C, the front end of which is of the same dimensions in horizontal plane as
the front end of the gauge. It corresponds in shape to the gauge on the sides
and ends. The tool D is rotated by any suitable mechanism, and the bar is turned
the outer end moving from left to right and the inner end kept firmly against the
post and the bar E, while the milling tool is operated. This cuts the slot upon the
principal and in the form above described.
in
Since this slot and the connections therein serve not only to hold the gauge
position when it has been set in proper position, but also to guide it to the proper
position and to maintain the shearing corner 4* always in the plane of the cut or
in a plane parallel therewith, it is essential that the rear end of the gauge be held
snugly in the curved slot and to this end a plug P is provided, fitted to move
snugly in the slot, having a hole through which the clamp screw is inserted,
this screw having a nut M on its lower end to hold the parts securely in place.
Instead of the plug P being made separate it may of course be made with the
gauge, though I prefer the construction shown as it is much less expensive, but I
do not limit myself as to the particular mechanism for holding the gauge snugly in
the slot.
I have referred to the outer end of the slot as being a certain distance from the
front when a line therefrom at right-angles to the line of cut, would cross said line
of cut, but practically the slot is carried outward farther to give space for the
connections which hold the gauge in the slot.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is ;-
1. In a mitre cutter, a gauge having a shearing edge, a post forming a bearing

page_text: the pivot pin engaging said guide way, and automatically adjustable in the move-
ment of the gauge to cause the shearing edge to move along the line of cut,
substantially as described.
2. In a mitre cutter, the combination of a gauge having a shearing edge, a post
forming a bearing for the gauge, an inclined guide way, a pivot pin and sliding
block, substantially as described.
3. In a mitre cutter, the combination of a gauge having a shearing edge, a guide
way and pin connection adjacent to the shearing edge between the gauge and the
machine frame and a pivoted link connected to the gauge and frame, substantially
as described.
4. In combination, the frame, the knife and shields projecting beyond the frame
and adjacent to the path of the knife, substantially as described.
5. In a mitring machine, a gauge having a curved bearing face struck from the
line of its shearing edge in combination with a post having a corresponding bearing
face, substantially as described.
6. In combination, the frame, the knife carriage having the knife, the lever 25
for moving the carriage relatively to the frame and the weight for the lever,
substantially as described.
7. In combination, the frame, the carriage movable in ways therein, the knife
secured to the carriage and having a lug or extension projecting above the upper
line of the cut and secured to the carriage, substantially as described.
8. In a mitre cutting machine, a gauge having a free front end and connections
for holding it closely in a slot in the base combined with a bearing post for the
front end and a base having a curved slot the parts of which are equidistant from a
shifting centre on a line identical or parallel with the line of cut, substantially as
described.
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool, Agents for the Applicant.