Improvements in Internal Roller Tube Cutters.
Year: 1890

page_text: Date of Application, 12th Feb., 1890
Complete Specification Left, 12th Dec., 1890-Accepted, 17th Jan. 1891
PROVISIONAL SPECIFICATION.
Improvements in Internal Roller Tube Cutters.
CHARLES WICKSTEED Stamford Road Works Kettering Engineer do hereby declare
the nature of this invention to be as follows:-
Hitherto it has been usual to force the rollers of internal tube cutters into the tube
to be cut, by means of a taper holt or mandril. By this means the cutters were forced
out but were not drawn back again into the socket after they had cut the tube. This
caused considerable inconvenience, the tool having to be wriggled to the detriment
of the cutters for some time before it could be withdrawn.
The object of my invention is to avoid this by providing means of drawing the
cutters back as well as forcing them forward by the same bolt. To do this I cut flats
on the bolt where the roller holders press upon it and dovetail the roller holders into
the bolt in the same way that the saddle of a lathe is dovetailed on the bed. The
roller holders thus sliding out and in of the case and up and down the bolt under
perfect control.
In order to render the tool still more efficient, in combination with the afore-
mentioned arrangement. I fix a ratchet on the tool which may be left handed so
that the simple action of holding the nut on the end of the bolt tightens it up and
forces the cutters to their work, when the ratchet is being worked.
13
1000
CHARLES WICKSTEED.
COMPLETE SPECIFICATION.
Improvements in Internal Roller Tube Cutters.
I, CHARLES WICKSTEED of Stamford Road Works, Kettering, in the County of
Northampton, 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 :-
Hitherto it has been usual to force the rollers or cutters of internal tube cutters
into the tube to be eut by means of a tapered bolt or mandrel. By this means the
cutters were forced out but were not drawn back again into the socket after they had
cut the tube; this caused considerable inconvenience the tool having to be wriggled
or worked about to the detriment of the cutters for some time before it could be
withdrawn. The chief object of my invention is to obviate this drawback by providing
means for retracting the cutters as well as forcing them out by the same bolt. To do
this I provide flats on the bolt where the roller holders or cages press upon it and
dovetail the roller holders in or onto the bolt in a manner similar to that in which
the saddle of a lathe is dovetailed to the bed.
In the accompanying drawings
Fig. is a longitudinal section of the complete tool and
Fig. 2 is a cross section on the line 2-2 of Fig. 1 looking in the direction
indicated by the figures.
Like letters represent like parts in both figures.
A is the body of the tool or socket carrying and adapted to be turned by the
handle B in a manner similar to that of an ordinary ratchet brace. is a screw
threaded cap or nut secured to A by any suitable means such as the screws D) so that
it can freely turn thereon and provided with a series of balls E to take the thrust of
the tool and allow freedom in turning. Screwing into the nut but freely held in
the body A is the bolt or mandrel F the operating end F1 of which is tapered as
indicated in the drawing with its larger end at the extremity of the bolt. The working

page_text: faces G of the tapered portion F¹ of the bolt F are preferably flattened and dovetailed
as indicated in Figure 2 and upon these slide the roller boxes or cages H. which are
provided with undercut recesses so as to engage with the dovetail faces G. The
operation is extremely simple. The tool which is generally used for cutting off a
boiler tube inside the tube plate is placed in the tube with the washers or collars K
bearing against the end of the tube any suitable number of washers being used so as
to make the distance between the line of the cutters and the face of the washers what
may be required in any particular case. The nut may now be turned by hand
drawing the bolt F into the body A and causing it to force outwards the cages H and
cutters. The tool is then revolved by the handle B as will be well understood.
During the operation the feed may be continued by holding the nut C by a wrench or
other suitable means so as to prevent its turning with the rest of the tool the result of
which will be that the mandrel F will be drawn still further through the body A and
the cutters forced further out.
When the operation is completed the nut is turned in the reverse direction so as
to force the bolt F towards the end of the body A whereby the smaller part of the
cone F is presented to the cutter boxes H which are thus drawn inwards into the
body of the tool and when the bolt has been pushed sufficiently far will be withdrawn
entirely clear of the tube and the tool can then be freely removed.
As the portion of the holt F where the tapered part F¹ joins the cylindrical part
though strong enough to stand the tensional strain will not stand a severe cross strain
or blow I provide the extension A which serves the double purpose of protecting the
end of the bolt F and also acting as a guide for it.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a tube cutter a roller or cutter which is positively retracted or withdrawn into
the body of the tool substantially as described.
2. In a tube cutter a tapered bolt such as F F¹ having dovetailed or undercut
working faces such as G substantially as and for the purpose described and illustrated
in the accompanying drawings.
3. In a tube cutter the combination with a tapered bolt such as F F¹ having
undercut working faces of a cutter box or cage such as H adapted to carry the cutter
and also dovetailed or similarly arranged so as to engage with the said undercut
working faces of the bolt substantially as and for the purpose described and illustrated
in the accompanying drawings.
4. In a tube cutter the combination with the cutter operating bolt of a body
extension such as A' for the purpose of serving as a guide for and also for protecting
the said bolt substantially as described and illustrated in Figure 1 of the accompanying
drawings.
5. The combination and arrangement of parts constituting the complete tube cutter
substantially as described and illustrated in the accompanying drawings.
Dated this 12th day of December 189
CHARLES WICKSTEED.
W. P. Thompson & Boult,
Agents for the Applicant.