IMPROVEMENTS IN APPLIANCES AND APPARATUS FOR HOLDING AND GRINDING TOOLS FOR CUTTING METAL
Year: 1882

page_text: LETTERS PATENT to Robert Rawlinson of the firm of Kendal and Gent of
Salford in the County of Lancaster, Machine Tool Makers for an invention of
IMPROVEMENTS IN APPLIANCES AND APPARATUS FOR HOLDING AND GRINDING
TOOLS FOR CUTTING METAL,
PROVISIONAL SPECIFICATION left by the said Robert Rawlinson at the
Office of the Commissioners of Patents on the 18th July 1882.
ROBERT RAWLINSON of the firm of Kendal and Gent of Salford in the County of
Lancaster, Machine Tool Makers. "IMPROVEMENTS IN APPLIANCES AND APPARATUS
FOR HOLDING AND GRINDING TOOLS FOR CUTTING METAL."
My Invention relates in the first place to the tool holders for holding the
hardened steel tools used in the turning and cutting of metals. Certain of these
tools are made of round steel held in holders by means of set-screws. According
to my Invention I hold the tool by means of a bolt which is formed with a wedge
or conical shaped head or with a head which is curved on one side to fit the tool.
When the bolt is tightened the tool is drawn into the groove or recess in the
holder and is jammed against the bottom or side of the said groove. The tool is
held more firmly than when held by means of a set-screw and is pressed more
directly against the solid metal of the holder. In a modification of the arrange-
ment I pinch the tool between the holder and a pinching plate or piece which is
tightened by means of a bolt.
In a form of holder wherein the angle of the tool is adjustable the tool being
held in a stud bolt or swivel piece I employ a wedge bolt to hold the tool so that
the tool can be removed and inserted without disturbing the angular adjustment.
In some cases I may use more than one bolt.
My Invention relates in the second place to the grinding of the tools. I carry
the tool to be ground upon the upper end of a swivel lever or frame which is fitted
with a sliding tool carriage or with a vibrating carriage or lever for traversing the
tool across the grinder. The tool is brought into contact with the grinder by
acting upon a shaft which is provided with a worm which gears with a spur
ID C

page_text: quadrant upon the said swivel fever or frame or a jointed or swivel screw and nut
or other means may be employed. I apply a spring or elastic medium between
the quadrant and lever frame or otherwise so as to impart a suitable amount of
elasticity to the pressure of the tool upon the grinder. The tool carriage may be
actuated by hand or by self-acting means as for example I may use a crank disc
and connecting rod.
"
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Robert Rawlinson in the Great Seal Patent Office on the
18th January 1883.
ROBERT RAWLINSON of the firm of Kendal and Gent of Salford in the County of
Lancaster, Machine Tool Makers "IMPROVEMENTS IN APPLIANCES AND APPARATUS
FOR HOLDING AND GRINDING TOOLS FOR CUTTING METAL"
My Invention relates in the first place to the tool holders for holding the
hardened steel tools used in the turning and cutting of metals. Certain of these
tools are made of round steel held in holders by means of set-screws. According
to my Invention I hold the tool by means of a bolt which is formed with a wedge
or conical shaped head or with a head which is curved on one side to fit the tool.
When the bolt is tightened the tool is drawn into the groove or recess in the
holder and is jammed against the bottom or side of the said groove. The tool is
held more firmly than when held by means of a set-screw and is pressed more
directly against the solid metal of the holder. In a modification of the arrange-
ment I pinch the tool between the holder and a pinching plate or piece which is
tightened by means of a bolt.
In a form of holder wherein the angle of the tool is adjustable the tool being
held in a stud, bolt or swivel piece I employ a wedge bolt to hold the cutting tool
so that the tool can be removed and inserted without disturbing the angular
adjustment. In some cases I use more than one bolt.
My Invention relates in the second place to the grinding of the tools. I carry
the tool to be ground upon the upper end of a swivel lever or frame which is fitted
with a sliding tool carriage or with a vibrating carriage or lever for traversing the
tool across the grinder. The tool is brought into contact with the grinder by
acting upon a shaft which is provided with a worm which gears with a spur
quadrant upon the said swivel lever or frame or a jointed or swivel screw and nut
or other means may be employed.
And in order that my invention may be fully understood I have attached
hereunto two sheets of drawings to which I shall now proceed to refer. Sheet 1
of the said drawings illustrates the first part of my Invention Fig: 1 being a side
view and Fig 2 a plan of the end of one of my improved tool holders. In the
said Figs a is the cranked end of the tool holder. b is the tool and c, c are the

page_text: holding bolts. The part a is hollowed to receive the round steel bar which
constitutes the tool. The heads of the two bolts are each formed on one side with
an inclined face c¹ and on the other side with a curved face c* which fits against
the side of the tool. It will be seen that when the bolts are "screwed up tight:
the tool is tightly gripped between the curved faces c² and the part a¹ of the holder
the faces c² acting as wedges to force the bolt heads tightly against the tool. The
gripping surfaces may if desired be roughened or corrugated so as to give a more
secure hold upon the tool I may use less or more than two bolts in one holder
and may vary the angular inclination of the bolts or arrange them at right angles
to the breadth of the holder and I may make the face c¹ in line with the bolt but I
prefer to retain the wedge action of the face. The aforesaid modification is
illustrated by Fig 3 wherein the tool is gripped between the end or edge of a
pinching plate or piece d and the end of the holder. The other end or side of the
plate & abuts against a shoulder upon the tool holder as seen at e so that when the
plate is drawn towards the body of the holder by tightening the bolt or bolts the
tool becomes tightly nipped as will be well understood. Figs 4 and 5 illustrate the
improvements in swivel tool holders. In this example the tool is held in a swivel
block which is formed with a shank which fits in a hole bored in the end of the
tool holder g as is usual. To secure the tool in the swivel block I employ a bolt h
which is formed with a wedge shaped edge as seen in Fig 4 so that when tightened
up the tool i is tightly jammed against the inclined shoulder f' upon the swivel
block. The drawings on sheet 2 are made to a scale of about three inches to the
foot and illustrate the second part of my invention Fig 6 representing a front
elevation and Fig 7 a side elevation of so much of a tool grinding apparatus as is
necessary to the illustration of my invention. In the said Figs j represents a
portion of a grindstone or revolving grinder and k a portion of the trough in
which the same revolves. In a bearing or in bearings a shaft is fitted to
swivel and to the ends of this shaft are secured the lower ends of two
side levers m, m. The upper ends of these levers are bored to receive
the ends of a cross bar n which is planed or otherwise trued to
receive a sliding carriage o to which a tool holder p can be secured. On
the underside of the said cross bar are formed spur rack teeth with which
gears a spur pinion q represented by dotted lines in Fig 7. The said pinion
is secured to one end of a shaft, which is fitted to revolve in a bearing in a part r
which is fast to the carriage and upon the outer end of the said shaft is secured a
hand wheel 8. By turning the said hand wheel the carriage o can be traversed to
and fro upon the cross bar. In the example the said cross bar is of nearly a square
shape in cross section having the corners removed and a flat to receive or hold the
rack teeth in place of the lower corner as indicated by the dotted lines in Fig 7
but the form of this cross bar may be greatly varied. Upon the two ends of the
cross bar are formed flanches n¹ in which are formed curved slots through which
pass bolts which secure the cross bar to the ends of the side levers. When the said
bolts are slackened the cross bar can be turned in its bearings in the upper ends of
the side levers whereby the angle at which the tool is presented to the grinder can
be adjusted the adjustment being preserved by tightening the bolts. A scale may
be marked upon one of the side levers as seen at t or upon one of the flanches upon
the cross bar to facilitate the adjustment. Upon one of the side levers is fixed or
formed a quadrant m³ which is cast or cut with worm teeth with which gears a
worm which is fixed upon a side shaft v. The said side shaft is provided with a
hand wheel w and is fitted to revolve in suitable bearings and to slide to some
extent in such bearings. A spiral spring extends between a fixed bearing or
abutment ย and a collar which is fixed upon the said shaft. The said spring
tends to slide the shaft in the direction indicated by the arrow so as to keep a
collar upon the shaft in contact with one of the bearings but by yielding permits a
movement in the contrary direction. The method of using the apparatus is as
follows: The tool to be ground having been fixed in the holder and the cross bar
adjusted so as to obtain the required angle of cutting edge the hand wheel w is

page_text: turned in the direction which will cause the tool to be brought into contact with
the grinder by the action of the worm upon the quadrant whereby the lever framo
is caused to turn in its bearings. The hand-wheel s is then turned to and fro so as
to traverse the tool to and fro across the face or edge of the grinder the pressure of
the tool upon the grinder being regulated by turning the hand-wheel w. It will be
seen that as the pressure required to turn the quadrant is transmitted through the
spiral spring a yielding pressure of the tool upon the grinder is obtained. A spring
may be interposed between the quadrant and the side lever or the spring may be
dispensed with if not considered to be necessary. I may vary the method of
carrying the tool so long as the lever frame m is used and may vary the arrange-
ments for traversing the tool holder carriage and may adopt a self-acting traverse
as for example I may traverse the carriage to and fro by means of a crank or
excentric connected with the carriage by means of a link or lever. I may use a
screw shaft and swivel nut in lieu of the worm and quadrant for actuating the
lever frame.
Having now fully set forth and indicated the nature of my said invention and
the manner in which and the means whereby I carry the same into practical effect
I would have it to be understood that I claim:
First the method of securing metal cutting tools in tool holders substantially as
set forth and indicated hereinbefore and in sheet 1 of the attached drawings.
Secondly securing cutting tools in tool holders by means of bolts substantially
in the manner set forth and indicated hereinbefore and in the attached drawings.
Thirdly the apparatus for grinding cutting tools substantially as set forth and
indicated hereinbefore and in and by the drawings on sheet 2.
Fourthly a tool holder carriage provided with arrangements for cross traversing
upon a cross piece which is carried by side levers or by a swivel frame which can
be turned upon a fulcrum to bring the tool in contact with the grinder and to
withdraw it therefrom substantially as set forth and indicated.
And lastly in a machine for grinding cutting tools carrying the tool to be ground
by means of a lever frame which vibrates or turns in bearings to bring the tool
into contact with the grinder and to withdraw the tool therefrom.
In witness whereof I the said Robert Rawlinson have hereunto set my hand
and seal this seventeenth day of January in the year of our Lord one
thousand eight hundred and eighty-three
Signed, sealed and delivered
in the presence of
EDWARD K. DUTTON
41 John Dalton St Manchester,
(Agent for the Patentee)
ROBERT RAWLINSON (L.S.)