Improvements in Tool Holders and Tools for Metal Planing Machines.
Year: 1899

page_text: Date of Application, 13th Nov., 1899
Complete Specification Left, 7th Aug., 1900-Accepted, 8th Sept., 190G
PROVISIONAL SPECIFICATION.
Improvements in Tool Holders and Tools for Metal Planing Machines.
1, JOSEPHI BARROW, of the Firm of T. Shanks and Company, of Union Iron
Works, Johnstone, in the County of Renfrew, North Britain, Engineer, do
hereby declare the nature of this invention to be as follows, that is to say:-
My invention comprises improvements in tool holders and tools which are
applicable for use in metal planing machines generally but are specially devised
for use in dealing with armour plates which have to be Harveyized. These
plates must be reduced by planing to a clean surface of equal thickness before
they are carburized; and as armour plates are now made of a much harder steel
than formerly this process of surfacing, owing to the tenacity of the steel, has
become a very slow and tedious operation with the tools at present in use, great
loss of time being also further incurred by having to take out the ordinary tools
frequently for grinding. The ordinary tools owing to their construction and
the manner in which they are held are also defective in operation as they
occasionally either dip unduly into the work or spring away from it.
To expedite the operation of the planing machine and to obviate the dis-
advantages named I, according to my invention, use a strong L-shaped tool
holder the upright portion of which is clamped to the tool plate of the machine
the other portion extending below the plate and having a recess formed in its
under side which recess has a number of transverse serrations formed in it.
The improved form of tool to be used with this holder consists of a straight
steel bar planed or ground on its under side to the section required and made
with a number of serrations stamped or machined on its upper surface which
serrations when the tool is clamped in position in the holder fit into the corre-
sponding serrations in the holder. The tool requires to be ground from time to
time at the end only this grinding thus not effecting the section given to it by
the planing of its underside; and the pitch of the serrations in the holder and
tool is the amount that, at one time, the tool can be set forward as it is ground
from time to time. The angle of relief to the tool is fixed at the best amount
on the tool holder and when clamped in position so that the front of the tool
where it cuts is in position to produce the desired cut the tool is held perfectly
rigid so that it can neither dip into the work or spring away from it. When
the cohesion and tenacity of the steel to be cut is so hard that it is impossible
to take a wide cut I form one or more narrow longitudinal grooves in the under-
Burface of the tool in order to split the cutting up into one or more narrow
strips. This form of tool is used preferably for roughing only a tool with a
straight face being used for finishing and it will also be seen that various sections
can be planed on the under side of the tool which will produce corresponding
sections on the work, the grinding of the tool on the end to sharpen the cutting
edge not altering the section of the tool.
Dated this Eleventh day of November 1899.
EDMUND HUNT,
Applicant's Agent.

page_text: Improvements in Tool Holders and Tools for Metal Planing Machines.
I, JOSEPH BARROW, of the Firm of T. Shanks and Company, of Union Iron
Works, Johnstone, in the County of Renfrew, North Britain, Engineer, 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, that is to say:-
My invention comprises improvements in tool holders and tools which are
applicable for use in metal planing machines generally, but are specially devised
for use in dealing with armour plates which have to be Harveyized. These
plates before being carburized must undergo a planing or surfacing process:
and as armour plates are now made of a much harder steel than formerly this
process of surfacing, owing to the tenacity of the steel, has become a very
slow and tedious operation with the tools at present in use.
The ordinary
toola owing to their construction and the manner in which they are held are
defective in operation as they occasionally either dig unduly into the work or
spring away from it. They also soon get blunted and great loss of time is
incurred by having to take them out frequently for grinding. By my invention
such defects and disadvantages are overcome thereby enabling any planing
operation to be carried out more quickly and efficiently than hitherto.
According to the invention the improvements comprise a strong L-shaped
tool holder, the upright stem of which is clamped or fixed to the tool plate of the
planing machine in the usual way, the other stem of the tool holder extending
below the tool plate, and having a recess or socket formed on its under side to
receive a tool formed with upper and side serrations to fit corresponding serra-
tions in the recessed part of the tool holder. The tool is a straight steel bar
which is planed or ground on its under side to the shape required, and it is
firmly fixed in the recessed serrated part by means of a suitable side clamping
attachment.
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
drawinga to bo hereinafter referred to in describing the improvements.
Figure, 1, of the drawings is an end elevation, and Figure, 2, is a side
elevation, partly in section, of the improvements. In these drawings the samo
reference letters are used to mark the same or like parts wherever they are
repeated.
In carrying out the invention there is provided a strong L shaped tool holder
the upright stem, A, of which is clamped or fixed to the tool plate, C, in the usual
way; the other stem, B, of the holder, extending below the tool plate and
having a recess, D, formed on its under side. The bottom of the recess is
formed with transverse serrations, E, preferably of rectangular shape in cross
section, the side of the recess being formed with longitudinal serrations, G,
preferably shaped in cross section. The improved form of tool to be used with
this holder consists of a steel bar, H, which is planed or grooved on its under
side to the shape required, and is made with serrated parts, J, K, stamped or
machined on its upper and side faces to fit the corresponding serrations, E, G,
on the tool holder, the serrated recess, D, being appropriately inclined longi-
tudinally as shown, so as to give the requisite angle of relief to the tool. The
tool requires to be ground from time to time to sharpen the cutting edge, but
as the grinding performed only on the end of the tool, it does not affect the
form of section given to it at the first by the planing or grinding of its under-
side. The tool is held firmly in the serrated recess, D, by means of a clamp

page_text: or cover, L, fitted to bear against a notched part, M, on the plain side face of
the tool, the clamp being fixed by screw bolts, N, which are screwed into the
holder. When the tool is clamped in position in the serrated recess, D, so
that the front of the tool where it cuts is set to produce the desired cut, the
tool is thus held perfectly rigid so that there is not the slightest tendency for it
to dig into the work or spring away from it. When the cohesion and tenacity
of the steel to be cut is so great that it is impossible to take a wide cut, a tool is
provided having its underside formed with longitudinal grooves, P', as shown
by dotted lines, in order thereby to split the cut into one or more narrow
strips. This form of tool is used preferably for roughing only, a tool with a
straight face being used for finishing. It will thus be seen that various sections
can be planed or cut on the underside of the tool which will produce corre-
sponding sections on the work. The stem, B, of the tool holder is preferably
provided with a thrust or adjusting screw, Q, the head, R, of the screw being
made to bear tightly against the underside of the tool plate, C, when the tool
holder is fixed in its working position, so that the upward thrust of the tool is
thereby transmitted to the tool plate. By this means the stem, B. is prevented
from springing upwards by the action of the tool. The screw, Q, also serves
as an adjusting device, as should the tool holder require to be removed from
the tool plate, it can afterwards be set in its proper vertical position by placing
it so that the head, R, of the screw bears against the tool plate, C, as before.
In some cases however the stem, B, of the tool holder may be arranged to bear
direct against the underside of the tool plate, C, the screw, Q, being thereby
dispensed with.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
Improvements in tool holders and tools for metal planing machines, com-
prising an L-shaped tool holder having its free stem, or the portion of the holder
not clamped to the tool plate, extending below the tool plate and formed with a
recess or socket to receive a tool having transverse and longitudinal serrations
formed respectively in its upper and side faces, to fit corresponding serrations
formed in the recess, the underside of the tool being made plain or ground,
the tool being fixed in the serrated recess by a clamp or cover which is bolted
against the side of the tool, the parts being constructed arranged and operating
substantially us and for the purposes hereinbefore described with reference to
the accompanying drawings.
Dated First day of August 1900.