IMPROVEMENTS IN MACHINERY FOR SAWING OR CUTTING WOOD
Year: 1872

page_text: LETTERS PATENT to William McLaren, Engineer to the Victoria
Patent Saw Mills Company, of Glasgow, in the County of Lanark,
North Britain, for the Invention of " IMPROVEMENTS IN MACHINERY FOR
SAWING OR CUTTING WOOD."
.
PROVISIONAL SPECIFICATION left by the said William McLaren
at the Office of the Commissioners of Patents, with his Petition,
on the 4th July 1872.
I, WILLIAM MCLAREN, Engineer to the Victoria Patent Saw Mills
Company, of Glasgow, in the County of Lanark, North Britain, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
MACHINERY FOR SAWING OR CUTTING WOOD," to be as follows, that is to
say:
This Invention relates to improvements in machinery of the kind
described in the Specification of Letters Patent obtained by August
Pentzlin, and dated 29 March 1860 (No. 808).

page_text: The improvements are designed to admit of two boards being sawn or
cut from a log for each traverse of the log. There is a single carriage for
the log, arranged and moved progressively as before; but there are two
distinct saw frames with the details for driving and guiding them, the
two saw frames being connected to diametrically opposite crank pins, so
that instead of their joint action producing a doubled lateral strain on
the log carriage the lateral strain of one opposes and neutralises that of
the other. The saw frame guides are on horizontal lathes or frames,
which are adjustable as to height upon vertical standards and which face
cach other, the guides of one being curved convexly as regards its lathe,
whilst those of the other are concave. The lathes or guide frames are
adjustable as to height by means of screw spindles applied to the
standards, the spindles on opposite sides being connected together by
cross shafts and bevil gearing.
The adjusting action is transmitted to both sets of spindles by bevil
gearing and two parallel horizontal shafts, and these horizontal shafts
have on them spur pinions with both of which a third pinion can be
made to gear when it is wished to adjust both lathes or guide frames to
the same extent. When this third pinion is out of gear the adjustments
can be made separately.
The driving cranks are by preference quite distinct and are fitted with
separate engaging appliances, so that one saw can be put into or out of
gear independently of the other if required.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William McLaren in the Great Seal Patent Office 2
on the 3rd January 1873.
TO ALL TO WHOM THESE PRESENTS SḤALL COME, I, WILLIAM
McLAREN, Engineer to the Victoria Patent Saw Mills Company, of
Glasgow, in the County of Lanark, North Britain, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her a
Letters Patent, bearing date the Fourth day of July, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William McLaren, Her special

page_text: <<
licence that I, the said William McLaren, my executors, administrators,
and assigns, or such others as I, the said William M°Laren, my execu-
tors, administrators, 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 might 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 MACHINERY FOR SAWING OR CUTTING WOOD," upon the condition (amongst
others) that I, the said William McLaren, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their
hands and seals, 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 William McLaren, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement, in writing, reference being had to the
acccompanying Drawings, that is to say:-
My said Invention relates to improvements in machinery of the kind
described in the Specification of Letters Patent obtained by August
Pentzlin, and dated 29 March 1860 (No. 808).
My improvements are designed to admit of two boards or planks being
sawn or cut from a log for cach traverse of the log.
And in order that my said Invention and the manner of performing
the same may be properly understood I hereunto append a Sheet of
explanatory Drawings, to be herein-after referred to, and representing a
duplex log sawing machine as made with my improvements. In these
Drawings the same reference numerals and letters are used to mark the
same or like parts wherever they are repeated.
Figure 1 on the Sheet of Drawings is a plan of a modification of
gearing employed for driving my improved combination of saws;
Figure 2, which is a continuation of Figure 1, but with the parts brought
nearer than they actually are, is a plan of the sawing apparatus; whilst
Figure 3 is a side elevation, corresponding to Figure 2.

page_text: The machinery is made and arranged in substantially the same
manner as that described in Pentzlin's Specification, with reference to
Sheet 2 of the Drawings of that Specification, so far as regards the
carriage A for supporting and moving the log B through the machine,
and various details in connection therewith, and so far as regards one
saw frame C, with its supporting and guiding lathe D, and the
standards E, and various details in connection therewith. And for the
sake of distinction I apply reference letters in the Drawings to these
parts and any others of the older parts to which I may have occasion to
refer, whilst I apply reference numerals to the added or newer parts, the
combination of which with the older parts constitutes my Invention.
The log carriage A is arranged and moved progressively as before,
excepting that the relative rate of progress is altered as may be required
by adjusting a frictional pulley 1 (Figure 2) between a pair of parallel
discs 2, 3, one of which drives whilst the other is driven in the train of
the feed motion, the pulley 1 being adjusted by means of a handle 4,
connected to its spindle by rods 5 and a bell-crank lever 6. There are
two distinct saw frames C and 7, with separate details for guiding and
driving them, the two saw frames C, 7, being connected to diametrically
opposite crank pins F and 8, so that instead of their joint action pro-
ducing a doubled lateral strain on the log carriage A the lateral strain
of one opposes and neutralises that of the other. The saw frame guides
G, 9, are on horizontal lathes or frames D, 10, which are adjustable as
to height upon vertical standards E, 11, and which face each other with
the lathes D, 10, on their inner edges, the guides G of one being curved
convexly as regards their lathe D, whilst those of the other are concave
as regards their lathe 10. The lathes or guide frames D, 10, are adjustable
as to height by means of screw spindles H, 12, applied to the standards
E, 11, the spindles on opposite sides of the log carriage A being
connected together by cross shafts J, 13, and bevil gearing.
The adjusting action is transmitted to both sets of spindles H, 12, by
bevil gearing and two parallel horizontal shafts 14, 15; and these
horizontal shafts have on them spur pinions 16, with both of which a
third pinion can be made to gear by means of a lever 17 when is
wished to adjust both lathes or guide frames D, 10, to the same extent.
When this third pinion is out of gear the adjustments can be made
separately. The added saw frame 7 has in connection with it various

page_text: minor details besides such as have been referred to, all of which are
similar to the corresponding details of the other saw frame D.
The driving cranks F, 8, are by preference quite distinct, and are
fitted with separate engaging appliances, so that one saw can be worked
independently of the other if required. The crank pins F, 8, are fixed
on discs 18, 18, on separate shafts 19, 19, cach provided with fast and
loose pulleys 20, 20, for driving belts. The shafts 19, 19, are geared
together by means of a counter shaft 21, having on it two spur
wheels 22, 22, which can be engaged or disengaged by means of sliding
clutches, and which gear with spur wheels 23, 23, on the shafts 19, 19.
Having thus particularly described our said Invention, and the manner
of performing the same, I have to state that I do not restrict myself to
the precise details herein described or delineated, but that what I
believe to be novel and original and claim as the Invention secured
to me by the herein-before recited Letters Patent is, the combining
together of two separate saw frames to act together upon a single
horizontally traversing log, substantially in the manner herein described.
and delineated.
In witness whereof, I, the said William McLaren, have hereunto
set my hand and scal, this Second day of January, in the year
of our Lord One thousand eight hundred and seventy-three.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
WM. MCLAREN. (L.S.)