AN IMPROVED TOOL FOR CUTTING CIRCULAR HOLES IN METAL PLATES, APPLICABLE FOR CUTTING THE TUBE PLATES FOR BOILERS AND FOR LIKE PURPOSES."
Year: 1880

page_text: LETTERS PATENT to Edward Henry Bennett, of 88, Leadenhall Street, in the
City of London, for an Invention of "AN IMPROVED TOOL FOR CUTTING
CIRCULAR HOLES IN METAL PLATES, APPLICABLE FOR CUTTING THE TUBE
PLATES FOR BOILERS AND FOR LIKE PURPOSES."
PROVISIONAL SPECIFICATION left by the said Edward Henry Bennett at
the Office of the Commissioners of Patents on the 11th September 1880.
EDWARD HENRY BENNETT, of 88; Leadenhall Street, in the City of London.
"AN IMPROVED TOOL FOR CUTTING CIRCULAR HOLES IN METAL PLATES,
APPLICABLE FOR CUTTING THE TUBE PLATES FOR BOILERS AND FOR LIKE
PURPOSES."
This Invention has for its object an improved tool for cutting circular holes in
metal plates, applicable for cutting the tube plates for boilers and for like
purposes.
At the present time in forming the holes in a tube plate to receive the boiler
tubes it is usual first to drill holes in the plate in the positions set out for the
centres of the tubes. The hole so formed in the plate is employed in each case as
a guide for a spindle or axis, which is passed through the hole, and fits it. The
spindle carries & disc or head, in which three or other number of tools are set, and
these tools, as the spindle is rotated and fed forward to the work, cut out a hole
of the proper size to receive the boiler tube; but it will be seen that this process
involves the labour of drilling the plate before the cutting out of the holes is
commenced. This labour 1 dispense with by the use of my improved tool.
My improved tool consists of a spindle adapted to be held in the head of a
machine drill or in a lathe. It is hollow, and receives within it a sliding rod
terminating in a cone point, and pressed forward by a strong coiled spring within
the spindle. The spindle also has a disc or head fixed upon it, on which are carried
the tools for cutting out the hole in the plate to receive the boiler tube. The only
preparation required by the tube plate before the tool is set to work upon it is
the marking of the centres for the holes with a centre punch. The tube plate so
Dine 1

page_text: marked having been brought to the machine the tool is fed forward until the cone
point of the rod within the hollow spindle enters the indentation, marking tho
centre for the hole. The cutting then commences; the forward feed of the tool or
work causes the cone point to be forced back as the cut advances into the spindle
against the resistance of the strong spring, whilst the point nevertheless controls
the cutters throughout, so as to ensure that the hole produced shall be true both in
form and size.
My improved tool is also applicable for cutting out annular pieces to serve as
flanges for pipes and for like uses, the tool being then armed with two sets of
cutters, the one set being arranged further from the centre than the other set.
The tool is also applicable in many other cases where it is required to cut
circular holes in or circular pieces from metal plates.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Henry Bennett in the Great Seal Patent Office on the 10th
March 1881.
EDWARD HENRY BENNETT, of 88, Leadenhall Street, in the City of London.
"AN IMPROVED TOOL FOR CUTTING CIRCULAR HOLES IN METAL PLATES,
APPLICABLE FOR CUTTING THE TUBE PLATES FOR BOILERS AND FOR LIKE
PURPOSES."
This Invention has for its object an improved tool for cutting circular holes in
metal plates, applicable for cutting the tube plates for boilers and for like purposes.
At the present time in forming the holes in a tube plate to receivo. the boiler
tubes it is usual first to drill holes in the plate in the positions set out for the
centres of the tubes. The hole so formed in the plate is employed in each caso as
a guide for a spindle or axis which is passed through the hole and fits it. The
spindle carries a disc or head in which three or other number of tools are set, and
these tools as the spindle is rotated and fed forward to the work cut out a hole of the
proper size to receive the boiler tube. But it will be seen that this process
involves the labour of drilling the plate before the cutting out of the holes is
commenced. This labour I dispenso with by the use of my improved tool.
My improved tool consists of a spindle adapted to be held in the head of a
machine drill or in a lathe. It is hollow and receives within it a sliding rod
terminating in a cone point and pressed forward by a strong coiled spring within
the spindle. The spindle also has a disc or head fixed upon it, in which are carried
the tools for cutting out the hole in the plate to receive the boiler tube. The only
preparation required by the tube plate before the tool is set to work upon it is the
marking of the centres for the holes with a centre punch. The tube plate so
marked having been brought to the machine the tool is fod forward until the cone
point of the rod within the hollow spindle enters the indentation marking the
centre for the hole, the cutting then commences, the forward feed of the tool or
work causes the cone point to be forced back as the cut advances into the spindle
against the resistance of the strong spring, whilst the point nevertheless controls
the cutters throughout so as to ensure that the hole produced shall be true both in
form and size.
My improved tool is also applicable for cutting out annular pieces to serve as
flanges for pipes and for like uses, the tool being then armed with two sets of
cutters the one set being arranged further from the centre than the other set.
The tool is also applicable in many other cases where it is required to cut
circular holes in or circular pieces from metal plates.
Having thus described the nature of my Invention, I will proceed to describe
more fully the manner of performing the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 of the Drawings hereunto annexed, shews a longitudinal section and
Figure 2 a plan view of a tool constructed as above described for cutting circular
holes in metal plates, applicable for cutting the tube plates for boilers and for like
purposes. A is a hollow spindle adapted to be held in a socket in the head of a
machine drill or in a lathe; B is a rod capable of sliding end wise to and fro in the
hollow of the spindle A; C is a coiled spring placed around the rod and bearing at
one end against a shoulder in the hollow of the spindle, and at the other end
against a collar on the rod so as to press the rod outwards from the hollow; D is
a screw cap screwed on to the end of the spindle, and which serves to keep the
rod B from coming out of place; the rod projects through this cap and at its end

page_text: has a cone point formed upon it; E is a disc, either_made in one piece with the
spindle A or fixed to it in the manner shewn in the Drawing, or otherwise; G are
radial slots through the disc E; H are blocks capable of being moved to and fro
along these slots by means of screws I. At the bottom of each block is a projecting
head which serves as a socket for holding the stem of one of the cutting tools K;
L are lock nuts on the end of the screws I, and M are screw bolts for binding
clamp plates N on to the top of the disc to lock and hold the blocks H when the
_cutting tools have been adjusted to their proper positions. The way in which I
prefer to form the cutting tools is clearly shown by the Drawing.
If annular pieces are to be cut out from metal plates the disc E might have four
or six radial slots formed in it for a greater number of tools to be used, and one
half of the number of tools might be set to make the inner circular cut and the
other half to make the outer circular cut.
Having thus described the nature of my Invention, and [the manner of
performing the same, I would have it understood that I claim the improved tool
substantially as herein before described, consisting of a combination of a hollow
spindle A, a pointed rod B partly contained within the spindle and pressed
outwards from it by a spring, and a disc E secured to or forming part of the spindle
-and-carrying-tool-holders-which-can-be-moved-towards-or-away-from-the-spindle.
In witness whereof, I, the said Edward Henry Bennett, have hereunto set my
_hand_and_seal,_this_Tenth_day_of_March,_in_the_year_of_our_Lord_One_
thousand eight hundred and eighty one.