Improvements in Expanding Reamers, Taps, and other similar Boring or Cutting Tools.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Expanding Reamers, Taps, and other similar Boring
or Cutting Tools.
I. THOMAS FARRINGTON, of 5. Spring Street, Great Lever, Bolton, in the County
of Lancaster, Cashier, do hereby declare the nature of this invention to be as
follows:
This invention relates primarily to reamers but is also applicable to taps or
other boring tools in which the cutting tool is in the form of a blade fitting
radially or approximately radially into a slot in a shank or mandrel and capable
of moving laterally therein.
The invention is designed to provide a tool that will bottom a hole" that is
to say one in which the cutting blades will extend to the end or project beyond
it so as to present a cutting edge at the end.
Hitherto the cutting blades have been placed to rest upon a movable or travel-
ling conical or inclined surface the cutter blades having no longitudinal movement.
This invention consists essentially in constructing the tool with stationary
inclined surfaces upon which the cutting blades rest and with a number of taper-
ing blades and causing the lateral or expansive movement of the blades by moving
them longitudinally along the inclined surfaces and in a special construction of
device for moving or setting the blades.
In carrying out the invention I cut a number of radial slots in the stock of the
tool to receive the cutters and the bottom of each slot forms an inclined plane upon
which the cutter rests. The base or stock of the tool is bored from the rear end
such hole meeting one end of the slots and cutting away the bottom of the slot
for some distance to allow the lower edge of the cutters to project through into the
interior. The hole in the interior is tapped for the greater part of its length to
receive a screw.
In the interior is inserted a sliding plug or the like which abuts against the
inwardly projecting ends of the cutters and as it is moved or advanced it pushes
the cutters along or up the incline.
The sliding plug may be cylindrical or other shape with a screw plug behind
it or a screw plug alone may be employed but I prefer to employ a plug of special
shape which will advance along the slots and thus travel further. For this purpose
I form the sliding plug with a number of rádial projections or blades by milling
out the intermediate metal and bore a conical or taper hole in the end thus form-
ing a number of blades or fingers which enter the radial slots of the tool from
the interior and follow the cutting blades.
A small pin is inserted in the end of the slots and a groove cut longitudinally
of the blade to hold them in position or a dove tail groove may be formed.
Dated 21st day of April 1899.
WM. P. THOMPSON & Co..
G, Bank Street, Manchester, Patent Agents.

page_text: Improvements in Expanding Reamers, Taps, and other similar Boring
or Cutting Tools.
1. THOMAS FARRINGTON, of 5. Spring Street, Great Lever, Bolton, in the County
of Lancaster, Cashier, 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 primarily to reamers but is also applicable to taps or
other boring tools in which the cutting tool is in the form of a blade fitting
radially or approximately radially into a slot in a shank or mandrel and capable
of advancing longitudinally and moving laterally therein.
The invention is designed to provide a tool that will "bottom a hole" that is
to say one in which the cutting blades will extend to the end or project beyond
it so as to present a cutting edge at the end,
Hitherto the cutting blades have been placed to rest upon a movable or travel-
ling conical or inclined surface the cutter blade having no longitudinal movement.
This invention consisis essentially in constructing the tool with stationary
inclined surfaces upon which the cutting blades rest and with a number of tupr
ing blades and causing the lateral or expansive movement of the blades by moving
them longitudinally along the inclined surfaces and in a special construction of
device for moving or setting the blades.
It will be fully described with reference to the accompanying drawings:
Fig. 1. Longitudinal sectional elevation.
Fig. Endelevation (showing two methods of securing the cutiers).
Fig. 3. Longitudinal sectional elevation showing modified arrangement for
traversing the cutters,
Fig. 4. Elevation of cutters showing modified arrangement of securing same in
position.
Fig. 5. End elevation of Fig. 4.
In the stock or holder A of the tool are cut a number of radial slots B to
receive the cutter C. The bottom of each of the radial slots B forms an inclined
plane upon which the cutters C are seated and the cutlers are of corresponding
inclined or tapered shape so that the peripheral or cutting edge thereof when in
position is parallel with the longitudinal central axis of the tool or the cutters
may be of any other desired shape to form a taper tool if desired.
The slots Bare cut out through the end of the holder A so that the ends
of the cutters C project to present a cutting edge at the end.
Two inclines may be formed at the bottom of the slots and upon the cutters
instead of a single continuous incline.
The base or stock of the tool is bored from the rear with a hole for some
distance into the interior such hole a meeting or cutting away the slots B for
some distance to allow of the lower edge or inner end of the cutters, projecting
through into the interior.
In the hole a is inserted a sliding plug to engage the ends of the cutters a
screw being employed to force it forwards and withdraw it. The interior of
the hole a is tapped for a part of its length to receive the screw. The plug D
may abut against the inwardly projecting ends of the cutters and as it is moved
or advanced pushes the cutters along or up the incline propelling them forward
in one direction only as shown in Fig. 1. Or the plug D may be formed with a
groove and collar d' at one end which engages slots a cut in the cutters C by
which the cutlers can be moved in both directions forwards and hackwards as
shown in Fig. 3.

page_text: The sliding plug may be cylindrical or other shape with a screw plug behind
it or a screw plug alone may be employed and the plug may be of special shape
which will advance along the slots B and thus travel further. In this latter
case I form the sliding plug with a number of radial projections or blades by
milling out the intermediate metal and hore a conical or taper hole in the end
thus forming a number of blades or fingers which enter the radial slots of the
tool from the interior and follow the cutting blades.
Instead of an ordinary nick in the adjusting screw to engage with a screw
driver, for the purpose of making it difficult or impossible for unauthorised
persons to alter the size or setting of the reamer I use two diameters of hole dª² d'
threaded or tapped having odd or bastard threads one right hand and the other
left hand a key for the same having corresponding seven threads, as in Fig. 3. It
is only possible then for the holder of the threaded key which fits these two holes
to turn the plug D in one direction or the other.
The cutters Care secured tightly in the slots B in any convenient or suitable
way. A groove may be formed longitudinally in the slots and a pin E inserted
therein or the cutters and slots may be of dovetail form as in Fig. 2. Or a
slit F may be made parallel with each slot B and the strip of metal formed
thereby them be expanded or forced against the cutters C by screws f thereby
clamping them in position as in Figs. 4 and 5.
The stock or holder A may be fitted with a shank or extension G fitted to
the end. It may be attached in any suitable way such as being screwed in as
Fig. 1, or may be of cylindrical or plug shape as atg in Fig. 3, with projections g¹
fitting into the slots or grooves cut into the end of the shank.
This construction of reamer or tap or similar tool whilst maintaining the
advantage of taking up the wear of the blades or cutters C on their outside edges
also presents an end or front cutting edge which can also be grooved and shaped
making it particularly applicable for the boring or reamering of blind holes"
or holes which are not hored through the metal.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1. A tool constructed with stationary inclined planes or surfaces and inclined
or tapering cutting tools or blades resting in slots thereon which are caused to
expand or move laterally by sliding them longitudinally over the inclined surface
upon which they rest substantially as described.
2. In a reamer tap or boring tool the combination with a stock or shank having
a number of radial (or approximately radial) slots each formed with an inclined
bottom surface of a number of tapering cutters or blades fitted therein and a
sliding plug to cause them to traverse the slots in one or both directions to give
them an expanding or lateral movement substantially as described.
3 A reamer tap or boring tool constructed substantially as described and shown.
Dated this 27th day of January 1900.
WM. P. THOMPSON & Co..
Manchester, Liverpool, & London, Patent Agents.