IMPROVEMENTS IN MACHINERY FOR CUTTING AND RENDING WOOD INTO SIZES SUITABLE FOR FIREWOOD OR FOR SIMILAR PURPOSES
Year: 1883

page_text: LETTERS PATENT to Thomas Andrew-Engineer of 135 Commercial Street
London. E. for an Invention of IMPROVEMENTS IN MACHINERY
FOR
CUTTING AND RENDING WOOD INTO SIZES SUITABLE FOR FIREWOOD OR FOR
SIMILAR PURPOSES
PROVISIONAL SPECIFICATION left by the said Thomas Andrew at the Offico
of the Commissioners of Patents on the 3rd January 1883.
THOMAS ANDREW Engineer of 135 Commercial Street-London, E IMPROVE-
MENTS IN MACHINERY FOR CUTTING AND RENDING WOOD, INTO SIZES SUITABLE
FOR FIREWOOD, OR FOR SIMILAR PURPOSES
I adapt certain mechanical contrivances to ordinary chopping knives or blades,
which being firmly attached to the front thereof, or else acting reciprocally there-
with form a stop, or block in front of the mouthpiece of the usual feed trough, at
such time as it is not covered wholly or in part, by the descent of the knife or
blade, but leaving the mouthpiece clear, and so allowing perfect freedom of exit to
the slice, cut or being cut, from the moment that the knife in its descent enters the
wood under operation-The space left between the mouthpiece where the knife
edge descends, and the front of the said stop or block, is regulated, to form the
thickness of the wood required to be sliced off, no other feed motion being necessary
than a constant gentle pressure from behind to force the blocks or pieces of wood
forward To effect this with a vertical knife or blade, which is the most usual form
of chopper, I attach to the knife or blade two straight pieces of metal, at right
angles to the edge thereof, and parallel with the knife itself, one on each side,
taking care that they shall not project over, or cover the sides of the mouthpiece
as it is necessary they should project downwards eight or nine inches, below the
bottom or edge of the knife, At the lower end of each of these two pieces of metal,
I form an adjustable flange, projecting inwards, so as to cover the sides of the

page_text: mouthpiece, about half an inch or less, but this flange or abutment, must not
commence nearer to the edge of the knife, than about half an inch less, than the
thickness of the wood cut, so that the mouthpiece is never quite clear of either the
knife or two projecting flanges, attached there unto, but which latter are quite clear
of the mouthpiece, the moment the knife strikes the wood (being attached to it)
To assure the forward projection of the divided slice, I attach to the centre of the
knife or blade, a little above its edge, a wedge shaped piece of wood or metal, which
prevents any entanglement of the slice with the projecting flanges, when they rise
with the knife-which so soon as it rises above the wood, allows it to make a fresh
abutment against the stops or flanges, hereinbefore described, owing to the pressure
mointained from behind-The wood under operation should be placed in the feeding
trough with its grain latteral to the edge of the knife, so as to cut rather than split
it. To reduce the slabs into sticks, they must be gathered into troughs of sheet
iron bent at right angles, whenco they are easily retransferred to the feeding
trough, and again passed through the machine in precisely the same way as were
the solid blocks, being piled one on the other, to the height of three or four inches,
and presented latterally to the knife edge, an adjustment of the space left between
the knife edge, and the flange regulating the thickness of the sticks cut

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Andrew in the Great Seal Patent Office on the 2nd July
1883.
THOMAS ANDREW Engineer of 135 Commercial Street London. E.
"IMPROVE-
MENTS IN MACHINERY FOR CUTTING AND RENDING WOOD INTO SIZES SUITABLE
FOR FIREWOOD OR FOR SIMILAR PURPOSES"
My said invention consists in the combination with an ordinary chopping knife
or blade worked by machinery of a peculiar arrangement of lateral stops flanges
or abutments so disposed as that whilst regulating the thickness of each slice cut
off as is well understood the said stops shall leave the discharge mouth of the
usual feed trough clear and thereby afford perfect freedom of exit to the slice cut
or being cut directly after the knife has entered the wood. Also in the com-
bination with the said knife of a wedge shaped projection or equivalent
contrivance carried by the front of the knife itself for the purpose of pushing
forward and completely detaching each slice separately as fast as it is severed
thereby preventing any entanglement of the slice with the said stops as they rise
or recede at the same time as the knife whilst at the same time thrusting onward
the pile of cut slices. The knife with its peculiar arrangement of stops may be
used either with or without the said wedge shaped projection or equivalent slice-
detaching contrivance or the latter contrivance may be applied to an ordinary
chopping blade or knife without the peculiar arrangement of lateral stops but I
prefer to employ the two arrangements conjointly as hereinafter described, I also
prefer that the wood to be operated upon (whether in the original form of a block
or in the form of a pile of previously cut slabs or slices to be subdivided into
sticks) should be so placed in the feeding trough that its grain shall run
horizontally and transversely to the trough or parallel with the cutting edge of
the knife in lieu of perpendicularly thereto, the blade entering the grain laterally
instead of at the end thereof thus cutting or slicing rather than splitting the wood.
No other feed motion is necessary beyond a gentle pressure applied by hand or
otherwise from behind in order to force the blocks or pieces of wood forward
along the feed trough and keep them up to the lateral stops or flanges before
mentioned.
And in order that my said invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the explanatory sheet of drawings hereunto annexed the
same letters of reference indicating corresponding parts in all the figures.
Figure 1 of my drawings is a front elevation of so much of a wood chopping
machine as is necessary to illustrate my improvements the knife, being shown at
half stroke.
Figure 2 is a corresponding vertical section of the knife and its carrier-slido
taken along the line 1-2 in figure 1 and showing the application to the front of
the knife of a peculiar self acting contrivance consisting of a moveable wedge-piece
or incline for detaching and pushing forward each slice separately as it is cut as
well as for urging onward the pile of cut slices.
Figure 3 is a vertical section showing the application of a more simple contrivance
consisting of a fixed wedge shaped piece secured to the front of the knife for the
same purpose.
Figure 4 is a detail of one of the lateral stops or abutment flanges detached
from the knife and figure is a detail front elevation of the knife-carrying slide
with the knife removed showing the lower portion of the slide cut away so as to

page_text: pass down the outer sides of the trough and thereby afford a firmer support to the
knife which is bolted to the two extended sides of the slide or carrier close up to
the cutting edge of the knife, thus obviating all tendency to spring when passing
through knots in the wood but I do not claim this slide as forming separately any
part of my said invention.
A is a portion of the front standard of a wood chopping machine. B the knife
actuating shaft working in suitable bearings on the upper end of the standard and
driven either direct or by a strap and pulley or gearing from a first motion shaft
situate in any convenient part of the machine but not shown in my drawing. C is
a crank pin or eccentric connected by a rod D with the slide E which is hero shown
as reciprocating in vertical guides F F bolted to the front of the standard.
G (figure 5) shows where the slide is cut away so as to pass freely down the outer
sides of the feed trough H supported on a bracket I cast or firmly secured to the
standard. The knife K is firmly secured by screws or bolts at a a to the lower
part of the slide E and to the front of the said knife on each side thereof are
secured by screws or otherwise at a a the two straight pieces of metal L (figure 4)
parallel to the body of the knife itself and at or about right angles to its cutting
edge bb. These pieces L are slotted as shown at c for the facility of vertical
adjustment. They should project say from eight to nine inches downwards or beyond
the cutting edge of the knife as shown but care must be taken that they do not
project over or cover the inner sides of the mouthpiece H except at their lower or
outer ends. If desired the pieces L may obviously be made to work independently
of the knife but in concert therewith by any suitable mechanical arrangement. At
the lower or outer end of each of these two pieces of metal L I form a lateral stop
flange or abutment & projecting inwards so as to overlap the inner opposite sides
of the mouthpiece to the extent of say half an inch more or less but the said stops
flanges or abutments must not commence nearer to the cutting edge of the knife
than half an inch or thereabouts less than the depth or thickness of the wood to
be cut so that the mouthpiece shall never be quite clear of both the knife and its
abutments dd at the same time but shall be perfectly clear of the stops or
abutments by the time the knife has entered say half an inch into the wood, hence
perfect freedom of exit of the severed pieces of wood is ensured. As the wood is
maintained in contact with the stops a the thickness of the slice will be regulated
as is well understood by the distance between the cutting edge and the inner
surface of the stops d which space may be varied either by packing up more or less
the pieces L or by making the lateral projections or stops & adjustable on the said
pieces, but in practice they may bo nade in one piece with the parts L as shown
in my drawing. The upper edge of each abutment d or that part nearest the
cutting edge should be bevelled away from the face of the block of wood as shown
at e (figures 2 and 3) in order to prevent it from catching the wood in its upward
or return stroke when the knife rises or recedes. Although the knife and lateral
stops or abutments d d embody to some extent the principle of action of the well
known joiners plane which principle has moreover been applied to wood chopping
machinery I would here point out that my peculiar arrangement of lateral stops
or flanges with reference to the cutting edge of the knife and the trough differs
materially from what has hitherto been proposed in as much as the said stops when
arranged and worked substantially as herein before described are moved out of the
way and present no obstruction to the discharge of the slice directly after the
knife has begun its cut which is not the case in wood chopping machines as
hitherto proposed. The said arrangement of lateral stops also affords ample space
for the introduction of a mechanical contrivance for thrusting away the cut slice
clear of the knife and machinery It is obvious that the same result may be
attained if the stops or flanges be caused to project slightly above the bottom of
the mouthpiece in lieu of from each side thereof provided the said stops are so
arranged as to be clear of the mouthpiece by the time the knife has commenced
its cut. The danger of the upward or back motion causing the stops to strike
against any chance projection on the face of the. wood under operation thereby

page_text: deranging the action of the machine is effectually prevented, First, by the very
slight amount of projection of the stops or flanges in front of the mouthpiece and
the bevelling outwards of the upper edges of such flanges as at e and Secondly by
the arrangement (which I shall now proceed to describe) nttached to the front of
the knife for forcing forward the cut slice and clearing it from the thrust of the side
flanges or stops at the back stroke. The arrangement which I prefer to employ for
this purpose is clearly illustrated at figures 1 and 2 and also in a simplified form at
figure 3. It consists of an inclined piece of metal M hinged at f to the front of the knife
or suspended from a cross rod g attached to the knife (see figures 1 and 2) and
bevelled at its lower edge to form a continuation of the bevel of the cutting edge
of the knife on the upper edge of which bevel it rests as shown clearly in figure 2.
An arm or projection N is attached to or formed in one with the part M so as to
project at or about right angles to the front thereof at or near its upper or hinged
end which arm by the time the knife has cut through the block comes in contact
with a cross bar or other fixed stop O attached to the standard or other convenient
stationary part of the machine and causes the part M to tilt forward on its hinges
or cross rod g into the position shown by dotted lines in figure 2 thereby pushing
the severed slice of wood a short distance from the knife the further descent of
which also causes the entire pile of cut slices to be moved forward. P is a spring
acting on the projection N for restoring the part M to its normal position against
the knife when making its upward or return stroke. For clean cutting wood a
simple wedge shaped piece of wood or metal may be permanently fixed to the front
of the knife or a piece of sheet iron M may be employed bent to a V shape as
shown in figure 3 and fixed to the front of the knife between the strips or pieces L
which carry the flanges or stops the point of the V or wedge being level or there-
abouts with the top of the bevel of the knife and forming an upward continuation
of the said bevel. But when the wood is of a nature to hang together by the
fibres the arrangement shown in figures 1 and 2 will be found to answer better in
practice.
In order to reduce or subdivide the slices or slabs to sticks no special cutters or
scorers are required as this may be accomplished by simply piling a number of
slices or slabs one on the other and passing the said pile through the feed trough
as before described the slabs being by preference so disposed in the trough as that
the grain of the wood shall run in the same direction in regard to the cutting
edge of the knife as hereinbefore described with reference to the original blocks.
Having now described and particularly ascertained the nature of my said
invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that what I consider to be novel and original
and therefore claim as the invention secured to me by the herein beforo in part
recited Letters Patent is :—
First. The peculiar combination and arrangement of machinery or apparatus for
cutting and rending wood into sizes suitable for firewood or for similar purposes as
hereinbefore described and illustrated by my drawings.
Second. The combination with the cutting or chopping knives or blados
employed in machines for cutting and rending wood into sizes suitable for fire-
wood or for similar purposes of stops flanges or projections carried by the knife or
working in concert therewith and so arranged as to leave the discharge mouth of
the feed trough clear and afford perfect freedom of exit to the slice cut or being cut
directly after the knife has entered the wood substantially as hereinbefore
described.
Third. The application to the cutting or chopping knives employed in the before
mentioned class of machines of strips or pieces of metal extending beyond the
cutting edge and so fixed to each side of the front of the knife as to leave the
mouth of the feed trough clear, the lower or forward ends of the said strips being
provided on their inner edges with slightly projecting lateral stops or flanges
commencing at a distance from the cutting edge rather loss than the thickness of

page_text: the block to be operated upon substantially as and for the purpose hereinbefore
described and illustrated by my drawings.
Fourth. The application to the front of a mechanically actuated chopping knife
of a fixed or a moveable or hinged inclined plate or wedge shaped_projection
arranged and caused to operate substantially in the manner and for the purpose
hereinbefore described and illustrated by my drawings.
Fifth. The combination with the knife of a chopping machine of the peculiar
arrangement of stops or flanges and the moveable or fixed wedge shaped projections
as and for the purpose specified.
In witness whereof I the said Thomas Andrew have hereunto set my hand
and seal this twenty seventh day of June in the year of our Lord one
thousand eight hundred and eighty three.
MADHY