Improvements in and relating to Tools and Holders for Use in Cutting, Boring, and Slotting Metal.
Year: 1896

page_text: Date of Application, 18th June, 1896
Complete Specification Left, 3rd Dec., 1896-Accepted, 9th Jan., 1897
PROVISIONAL SPECIFICATION.
Improvements in and relating to Tools and Holders for Use in
Cutting, Boring, and Slotting Metal.
I, WILLIAM HENRY HARDY, Brassfounder, of the Hartlepool Brass and
Engineering Works, Hartlepool, in the County of Durham, do hereby declare the
nature of this invention to be as follows:-
My invention relates to tools of the class used for cutting, boring and slotting
metal, such as iron, brass, or the like, in which a cutting edge is provided at the
end of a tool holder or shaft. This cutting edge is often formed all of a piece
with the shaft so that to change the cutting tool the holder or shaft must be
changed with it, which involves a heavy stock of loose tools where a variety of
cutting operations are required. Or if the cutting tool be detachably secured to
the holder or shaft, this has hitherto been effected by means of a through hole to
receive the cutter which is secured by a set screw, and the main defect of this
construction is that the edge of the cutter cannot be made to extend beyond or
about the end of the tool shaft in the manner essential for a boring tool, and
tools as hitherto constructed with detachable cutters can only be used for certain
purposes.
By my invention I combine the advantages of the tool with its cutter made all
in a piece with the tool holder or shaft with the advantages of the tool as hitherto
constructed with a detachable cutter that is to say that I effect a great saving of
tool steel material by making the same tool holder or shaft adaptable to a number
of cutters and I enable the point or edge of the cutter to be brought up to or as
far beyond the end of the tool shaft as is usually required in ordinary cutting
operations.
In a tool constructed according to my invention the holder or shaft is slotted or
grooved across the end and along opposite sides of the shaft so that a clamp formed
by a crosshead and two parallel bars can slide along the grooves and close into
the crosshead slot of the tool holder or shaft and so clamp in a detachable
cutting tool. A nut screwed on to the tool shaft engages with the parallel bars
of the clamp, the ends of which are turned up or set up for the purpose, and the
clamp is applied or relaxed by turning the nut which can be readily done by
hand,
Deted this 17th day of June 1806
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.

page_text: Improvements in and relating to Tools and Holders for Use in
Cutting, Boring, and Slotting Metal.
I, WILLIAM HENRY HARDY, Brassfounder, of the Hartlepool Brass and
Engineering Works, Hartlepool, in the County of Durham, 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 relates to tools of the class used for cutting, boring and slotting
metal, such as iron, brass or the like, in which a cutting edge is provided at the
end of a holder or shaft. This cutting edge is often formed all of a piece with
the shaft, so that to change the cutting tool the holder or shaft must be changed
with it, which involves a heavy stock of loose tools where a variety of cutting
operations are required. Or if the cutting tool be detachably secured to the
bolder or shaft, this has hitherto been effected by means of a through hole to
receive the cutter which is secured by a set screw and the main defect of this
construction is that the edge of the cutter cannot be made to extend beyond or
about the end of the tool shaft in the manner essential for a boring tool, and
tools as hitherto constructed with detachable cutters can ouly be used for certain
purposes.
By my invention I combine the advantages of the tool with its cutter made all
in a piece with the tool holder or shaft with the advantages of the tool as hitherto
constructed with a detachable cutter, that is to say that I effect a great saving of
tool steel material by making the same tool holder or shaft adaptable to a number
of cutters and I enable the point or edge of the cutter to be brought up to or as
far beyond the end of the tool shaft as is usually required in ordinary cutting
operations.
A machine tool holder constructed according to my invention is characterized
by a simplicity of parts by which the tool can be removed, replaced and thoroughly
secured without the use of set screws, wedges or other similar methods.
In the ordinary application of set screws for securing the tool in the holder,
sufficient depth of hole cannot be obtained to provide the necessary number of
threads requisite to withstand the strain of frequent slackening and tightening of
the set screw without stripping the thread in an unreasonably short time, causing
great annoyance through delay and cost of repairs.
In my improved tool holder not only is this trouble and cost avoided but owing
to the absence of set screws, wedges or other projecting appliances for securing the
tool, the cutting edge of the tool can be traversed to the extreme length or depth
of the bore, and a larger shaft relatively to the size of the hole being bored can
be used, as for instance an 1" diameter tool shaft for an 11" hole.
Having described the nature of my invention and its utility, I will now proceed
to further explain the same by reference to the drawing hereto annexed and the
manner by which my said improvements are to be carried into practice.
In the drawing
Fig. 1 illustrates the tool holder in elevation complete in all its parts with the
cutting tool fixed in position and shown transversely.
Fig. 2 is a similar view showing the cutting tool end wise.
In Fig. 3 the shaft or tool holder is shown from the same point of view as in
Fig. 1, but stripped of the cutting tool and all that is detachable in the means for
securing it to the tool holder.
Fig. 4 illustrates in part sectional view the said detachable means of securing
the tool, Fig. 5 being a plan view of Fig. 4.

page_text: In carrying out my invention the tool holder or shaft a is slotted or grooved
across the end at a¹ and along opposite sides of the shaft at a so that a clamp b
formed by a cross head 6 and two parallel bars 6 can slide along the grooves a
and close into the crosshead slot a¹ of the tool holder or shaft a and so clamp in a
detachable cutting tool c which may be diamond pointed as shown in Fig. 1 or of
any other form of cutting edge required in the operations to which my invention is
applicable and I will here observe that the point of the tool can be made to extend
beyond the extreme end of the clamp b of the tool shaft a the practical advantage
of which is obvious. A nut d screwed onto the screw shaft a engages with the
parallel bars 6 of the clamp the ends 63 of which are turned up or set up for the
purpose and the clamp is applied or relaxed by turning the nut to the right or
left which can readily be done by hand.
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 :-
In tools and their holders for cutting, boring and slotting metal, the particular
arrangement and combination of parts in which a cutting tool is detachably secured
at the end of a shaft by means of a clamp fitted in slots along the shaft and
adjustably secured therein, substantially in the manner and for the purpose as
herein before described with reference to the accompanying drawing.
3000
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.