Improvements in Certain Files.
Year: 1892

page_text: Date of Application, 23rd May, 1892
Complete Specification Left, 23rd Feb., 1893-Accepted, 1st Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Certain Files.
I, JOHN LAWRENCE STEWART, of Dumb Mill, Frizinghall near Bradford, in the
County of York, Manufacturer, do hereby declare the nature of this invention to
be as follows:-
This invention relates to improvements in that class of files for cutting, abrading
and smoothing metal and other substances in which the teeth are formed on the
edges of steel plates mounted side by side in a suitable frame or holder and its
object is to provide a more accurate, rigid and durable frame or holder.
For this purpose I form said frame or holder from the solid metal by milling the
longitudinal groove to receive the cutting plates out of a solid bar of mild steel or
other suitable metal. A lip or tongue is left along the edge of each side of the groove
to engage the notches at the ends of the cutting plates and hold them in position.
A sliding block is fitted at the handle end of the frame to adjust the pressure
between the plates and a stationary block is fitted in the other end to determine
the angle of such plates.
The end block in which the adjusting screw is fitted is preferably made
removable and for this purpose the back of the frame is cut away so as to leave
the sides projecting and the end block is secured to these projecting sides by means
of pins, cotters or the like.
Dated this 21st day of May 1892.
DRACUP & NOWELL,
Bradford, Agents.
COMPLETE SPECIFICATION.
Improvements in Certain Files.
I, JOHN LAWRENCE STEWART, of Dumb Mill, Frizinghall, near Bradford, in
the County of York, 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 :-
This invention relates to improvements in that class of file for cutting, abrading,
and smoothing metal and other substances in which the teeth are formed on the
edges of steel plates mounted side by side in a suitable frame or holder and its
object is to provide a more accurate, rigid and durable frame or holder.
For this purpose I form the said frame or holder from the solid metal by milling
the longitudinal groove to receive the cutting plates out of a solid bar of mild
steel or other suitable metal. A lip or tongue is left along the edge of each side
of the groove to engage the notches at the ends of the cutting plates and hold them
in position. A sliding block is fitted at the handle end of the frame to adjust the
pressure between the plates and a stationary block is fitted in the other end to
determine the angle of such plates.
The end block in which the adjusting screw is fitted is preferably made removable
and for this purpose the back of the frame is cut away so as to leave the sides pro-
jecting and the end block is secured to these projecting sides by means of pins,
cotters or the like.
Reference is to be had to the accompanying sheet of drawings forming a part of
this Specification in which similar letters of reference indicate corresponding parts
in each of the figures.
Figure 1, represents a view of the file with most of the teeth plates removed to
TDC37

page_text: show the frame or holder and a portion of the latter is represented as broken away to
enable it to be shown on a larger scale.
Figure 2, is an edge view of the same.
Figure 3, is a separate view of the frame or holder.
Figure 4, is a cross section of the same and Figure 5, is an end view with
the handle removed.
The longitudinal groove A in the frame or holder B for the reception of the
teeth plates C is milled out so as to leave an overhanging lip D along each side E
of the holder to engage the usual notches formed in the ends of the teeth plates.
A fixed block F is secured in the front end of the groove A for the teeth plates to
bear against and an adjustable block G is fitted in the other end adapted to be
adjusted by the screw H fixed in the handle J. A female thread is formed in the
hole K of the end block L fitting the screw K. This block L is provided
with holes M, M adapted to fit the projections N, N formed at the end of the
holder B (by cutting away the bottom of the groove A) and it is secured
thereon by the pins 8, O passed through L so as to engage the approximately
semi-circular notches P, P in N.
By this construction I am enabled to produce holders cheaply which are
practically perfectly true which is a matter of the highest importance in this class
of file.
Instead of milling the holders out of solid bars I prefer to use bars rolled
specially for the purpose with a portion of the groove A already formed.
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 :
Forming the plate or holder for the above described class of file of solid metal
with the sides or lips D milled out, substantially as herein shown and described.
Dated this 21st day of February 1893.
DRACUP & NOWELL.
Bradford, Agents.